1 | /* |
2 | ** 2001-09-15 |
3 | ** |
4 | ** The author disclaims copyright to this source code. In place of |
5 | ** a legal notice, here is a blessing: |
6 | ** |
7 | ** May you do good and not evil. |
8 | ** May you find forgiveness for yourself and forgive others. |
9 | ** May you share freely, never taking more than you give. |
10 | ** |
11 | ************************************************************************* |
12 | ** This header file defines the interface that the SQLite library |
13 | ** presents to client programs. If a C-function, structure, datatype, |
14 | ** or constant definition does not appear in this file, then it is |
15 | ** not a published API of SQLite, is subject to change without |
16 | ** notice, and should not be referenced by programs that use SQLite. |
17 | ** |
18 | ** Some of the definitions that are in this file are marked as |
19 | ** "experimental". Experimental interfaces are normally new |
20 | ** features recently added to SQLite. We do not anticipate changes |
21 | ** to experimental interfaces but reserve the right to make minor changes |
22 | ** if experience from use "in the wild" suggest such changes are prudent. |
23 | ** |
24 | ** The official C-language API documentation for SQLite is derived |
25 | ** from comments in this file. This file is the authoritative source |
26 | ** on how SQLite interfaces are supposed to operate. |
27 | ** |
28 | ** The name of this file under configuration management is "sqlite.h.in". |
29 | ** The makefile makes some minor changes to this file (such as inserting |
30 | ** the version number) and changes its name to "sqlite3.h" as |
31 | ** part of the build process. |
32 | */ |
33 | #ifndef SQLITE3_H |
34 | #define SQLITE3_H |
35 | #include <stdarg.h> /* Needed for the definition of va_list */ |
36 | |
37 | /* |
38 | ** Make sure we can call this stuff from C++. |
39 | */ |
40 | #ifdef __cplusplus |
41 | extern "C" { |
42 | #endif |
43 | |
44 | |
45 | /* |
46 | ** Provide the ability to override linkage features of the interface. |
47 | */ |
48 | #ifndef SQLITE_EXTERN |
49 | # define SQLITE_EXTERN extern |
50 | #endif |
51 | #ifndef SQLITE_API |
52 | # define SQLITE_API |
53 | #endif |
54 | #ifndef SQLITE_CDECL |
55 | # define SQLITE_CDECL |
56 | #endif |
57 | #ifndef SQLITE_APICALL |
58 | # define SQLITE_APICALL |
59 | #endif |
60 | #ifndef SQLITE_STDCALL |
61 | # define SQLITE_STDCALL SQLITE_APICALL |
62 | #endif |
63 | #ifndef SQLITE_CALLBACK |
64 | # define SQLITE_CALLBACK |
65 | #endif |
66 | #ifndef SQLITE_SYSAPI |
67 | # define SQLITE_SYSAPI |
68 | #endif |
69 | |
70 | /* |
71 | ** These no-op macros are used in front of interfaces to mark those |
72 | ** interfaces as either deprecated or experimental. New applications |
73 | ** should not use deprecated interfaces - they are supported for backwards |
74 | ** compatibility only. Application writers should be aware that |
75 | ** experimental interfaces are subject to change in point releases. |
76 | ** |
77 | ** These macros used to resolve to various kinds of compiler magic that |
78 | ** would generate warning messages when they were used. But that |
79 | ** compiler magic ended up generating such a flurry of bug reports |
80 | ** that we have taken it all out and gone back to using simple |
81 | ** noop macros. |
82 | */ |
83 | #define SQLITE_DEPRECATED |
84 | #define SQLITE_EXPERIMENTAL |
85 | |
86 | /* |
87 | ** Ensure these symbols were not defined by some previous header file. |
88 | */ |
89 | #ifdef SQLITE_VERSION |
90 | # undef SQLITE_VERSION |
91 | #endif |
92 | #ifdef SQLITE_VERSION_NUMBER |
93 | # undef SQLITE_VERSION_NUMBER |
94 | #endif |
95 | |
96 | /* |
97 | ** CAPI3REF: Compile-Time Library Version Numbers |
98 | ** |
99 | ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header |
100 | ** evaluates to a string literal that is the SQLite version in the |
101 | ** format "X.Y.Z" where X is the major version number (always 3 for |
102 | ** SQLite3) and Y is the minor version number and Z is the release number.)^ |
103 | ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer |
104 | ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same |
105 | ** numbers used in [SQLITE_VERSION].)^ |
106 | ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also |
107 | ** be larger than the release from which it is derived. Either Y will |
108 | ** be held constant and Z will be incremented or else Y will be incremented |
109 | ** and Z will be reset to zero. |
110 | ** |
111 | ** Since [version 3.6.18] ([dateof:3.6.18]), |
112 | ** SQLite source code has been stored in the |
113 | ** <a href="http://www.fossil-scm.org/">Fossil configuration management |
114 | ** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to |
115 | ** a string which identifies a particular check-in of SQLite |
116 | ** within its configuration management system. ^The SQLITE_SOURCE_ID |
117 | ** string contains the date and time of the check-in (UTC) and a SHA1 |
118 | ** or SHA3-256 hash of the entire source tree. If the source code has |
119 | ** been edited in any way since it was last checked in, then the last |
120 | ** four hexadecimal digits of the hash may be modified. |
121 | ** |
122 | ** See also: [sqlite3_libversion()], |
123 | ** [sqlite3_libversion_number()], [sqlite3_sourceid()], |
124 | ** [sqlite_version()] and [sqlite_source_id()]. |
125 | */ |
126 | #define SQLITE_VERSION "3.33.0" |
127 | #define SQLITE_VERSION_NUMBER 3033000 |
128 | #define SQLITE_SOURCE_ID "2020-08-14 13:23:32 fca8dc8b578f215a969cd899336378966156154710873e68b3d9ac5881b0ff3f" |
129 | |
130 | /* |
131 | ** CAPI3REF: Run-Time Library Version Numbers |
132 | ** KEYWORDS: sqlite3_version sqlite3_sourceid |
133 | ** |
134 | ** These interfaces provide the same information as the [SQLITE_VERSION], |
135 | ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros |
136 | ** but are associated with the library instead of the header file. ^(Cautious |
137 | ** programmers might include assert() statements in their application to |
138 | ** verify that values returned by these interfaces match the macros in |
139 | ** the header, and thus ensure that the application is |
140 | ** compiled with matching library and header files. |
141 | ** |
142 | ** <blockquote><pre> |
143 | ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER ); |
144 | ** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 ); |
145 | ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 ); |
146 | ** </pre></blockquote>)^ |
147 | ** |
148 | ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION] |
149 | ** macro. ^The sqlite3_libversion() function returns a pointer to the |
150 | ** to the sqlite3_version[] string constant. The sqlite3_libversion() |
151 | ** function is provided for use in DLLs since DLL users usually do not have |
152 | ** direct access to string constants within the DLL. ^The |
153 | ** sqlite3_libversion_number() function returns an integer equal to |
154 | ** [SQLITE_VERSION_NUMBER]. ^(The sqlite3_sourceid() function returns |
155 | ** a pointer to a string constant whose value is the same as the |
156 | ** [SQLITE_SOURCE_ID] C preprocessor macro. Except if SQLite is built |
157 | ** using an edited copy of [the amalgamation], then the last four characters |
158 | ** of the hash might be different from [SQLITE_SOURCE_ID].)^ |
159 | ** |
160 | ** See also: [sqlite_version()] and [sqlite_source_id()]. |
161 | */ |
162 | SQLITE_API SQLITE_EXTERN const char sqlite3_version[]; |
163 | SQLITE_API const char *sqlite3_libversion(void); |
164 | SQLITE_API const char *sqlite3_sourceid(void); |
165 | SQLITE_API int sqlite3_libversion_number(void); |
166 | |
167 | /* |
168 | ** CAPI3REF: Run-Time Library Compilation Options Diagnostics |
169 | ** |
170 | ** ^The sqlite3_compileoption_used() function returns 0 or 1 |
171 | ** indicating whether the specified option was defined at |
172 | ** compile time. ^The SQLITE_ prefix may be omitted from the |
173 | ** option name passed to sqlite3_compileoption_used(). |
174 | ** |
175 | ** ^The sqlite3_compileoption_get() function allows iterating |
176 | ** over the list of options that were defined at compile time by |
177 | ** returning the N-th compile time option string. ^If N is out of range, |
178 | ** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_ |
179 | ** prefix is omitted from any strings returned by |
180 | ** sqlite3_compileoption_get(). |
181 | ** |
182 | ** ^Support for the diagnostic functions sqlite3_compileoption_used() |
183 | ** and sqlite3_compileoption_get() may be omitted by specifying the |
184 | ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time. |
185 | ** |
186 | ** See also: SQL functions [sqlite_compileoption_used()] and |
187 | ** [sqlite_compileoption_get()] and the [compile_options pragma]. |
188 | */ |
189 | #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS |
190 | SQLITE_API int sqlite3_compileoption_used(const char *zOptName); |
191 | SQLITE_API const char *sqlite3_compileoption_get(int N); |
192 | #else |
193 | # define sqlite3_compileoption_used(X) 0 |
194 | # define sqlite3_compileoption_get(X) ((void*)0) |
195 | #endif |
196 | |
197 | /* |
198 | ** CAPI3REF: Test To See If The Library Is Threadsafe |
199 | ** |
200 | ** ^The sqlite3_threadsafe() function returns zero if and only if |
201 | ** SQLite was compiled with mutexing code omitted due to the |
202 | ** [SQLITE_THREADSAFE] compile-time option being set to 0. |
203 | ** |
204 | ** SQLite can be compiled with or without mutexes. When |
205 | ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes |
206 | ** are enabled and SQLite is threadsafe. When the |
207 | ** [SQLITE_THREADSAFE] macro is 0, |
208 | ** the mutexes are omitted. Without the mutexes, it is not safe |
209 | ** to use SQLite concurrently from more than one thread. |
210 | ** |
211 | ** Enabling mutexes incurs a measurable performance penalty. |
212 | ** So if speed is of utmost importance, it makes sense to disable |
213 | ** the mutexes. But for maximum safety, mutexes should be enabled. |
214 | ** ^The default behavior is for mutexes to be enabled. |
215 | ** |
216 | ** This interface can be used by an application to make sure that the |
217 | ** version of SQLite that it is linking against was compiled with |
218 | ** the desired setting of the [SQLITE_THREADSAFE] macro. |
219 | ** |
220 | ** This interface only reports on the compile-time mutex setting |
221 | ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with |
222 | ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but |
223 | ** can be fully or partially disabled using a call to [sqlite3_config()] |
224 | ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], |
225 | ** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the |
226 | ** sqlite3_threadsafe() function shows only the compile-time setting of |
227 | ** thread safety, not any run-time changes to that setting made by |
228 | ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe() |
229 | ** is unchanged by calls to sqlite3_config().)^ |
230 | ** |
231 | ** See the [threading mode] documentation for additional information. |
232 | */ |
233 | SQLITE_API int sqlite3_threadsafe(void); |
234 | |
235 | /* |
236 | ** CAPI3REF: Database Connection Handle |
237 | ** KEYWORDS: {database connection} {database connections} |
238 | ** |
239 | ** Each open SQLite database is represented by a pointer to an instance of |
240 | ** the opaque structure named "sqlite3". It is useful to think of an sqlite3 |
241 | ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and |
242 | ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] |
243 | ** and [sqlite3_close_v2()] are its destructors. There are many other |
244 | ** interfaces (such as |
245 | ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and |
246 | ** [sqlite3_busy_timeout()] to name but three) that are methods on an |
247 | ** sqlite3 object. |
248 | */ |
249 | typedef struct sqlite3 sqlite3; |
250 | |
251 | /* |
252 | ** CAPI3REF: 64-Bit Integer Types |
253 | ** KEYWORDS: sqlite_int64 sqlite_uint64 |
254 | ** |
255 | ** Because there is no cross-platform way to specify 64-bit integer types |
256 | ** SQLite includes typedefs for 64-bit signed and unsigned integers. |
257 | ** |
258 | ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. |
259 | ** The sqlite_int64 and sqlite_uint64 types are supported for backwards |
260 | ** compatibility only. |
261 | ** |
262 | ** ^The sqlite3_int64 and sqlite_int64 types can store integer values |
263 | ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The |
264 | ** sqlite3_uint64 and sqlite_uint64 types can store integer values |
265 | ** between 0 and +18446744073709551615 inclusive. |
266 | */ |
267 | #ifdef SQLITE_INT64_TYPE |
268 | typedef SQLITE_INT64_TYPE sqlite_int64; |
269 | # ifdef SQLITE_UINT64_TYPE |
270 | typedef SQLITE_UINT64_TYPE sqlite_uint64; |
271 | # else |
272 | typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; |
273 | # endif |
274 | #elif defined(_MSC_VER) || defined(__BORLANDC__) |
275 | typedef __int64 sqlite_int64; |
276 | typedef unsigned __int64 sqlite_uint64; |
277 | #else |
278 | typedef long long int sqlite_int64; |
279 | typedef unsigned long long int sqlite_uint64; |
280 | #endif |
281 | typedef sqlite_int64 sqlite3_int64; |
282 | typedef sqlite_uint64 sqlite3_uint64; |
283 | |
284 | /* |
285 | ** If compiling for a processor that lacks floating point support, |
286 | ** substitute integer for floating-point. |
287 | */ |
288 | #ifdef SQLITE_OMIT_FLOATING_POINT |
289 | # define double sqlite3_int64 |
290 | #endif |
291 | |
292 | /* |
293 | ** CAPI3REF: Closing A Database Connection |
294 | ** DESTRUCTOR: sqlite3 |
295 | ** |
296 | ** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors |
297 | ** for the [sqlite3] object. |
298 | ** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if |
299 | ** the [sqlite3] object is successfully destroyed and all associated |
300 | ** resources are deallocated. |
301 | ** |
302 | ** Ideally, applications should [sqlite3_finalize | finalize] all |
303 | ** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and |
304 | ** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated |
305 | ** with the [sqlite3] object prior to attempting to close the object. |
306 | ** ^If the database connection is associated with unfinalized prepared |
307 | ** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then |
308 | ** sqlite3_close() will leave the database connection open and return |
309 | ** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared |
310 | ** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups, |
311 | ** it returns [SQLITE_OK] regardless, but instead of deallocating the database |
312 | ** connection immediately, it marks the database connection as an unusable |
313 | ** "zombie" and makes arrangements to automatically deallocate the database |
314 | ** connection after all prepared statements are finalized, all BLOB handles |
315 | ** are closed, and all backups have finished. The sqlite3_close_v2() interface |
316 | ** is intended for use with host languages that are garbage collected, and |
317 | ** where the order in which destructors are called is arbitrary. |
318 | ** |
319 | ** ^If an [sqlite3] object is destroyed while a transaction is open, |
320 | ** the transaction is automatically rolled back. |
321 | ** |
322 | ** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)] |
323 | ** must be either a NULL |
324 | ** pointer or an [sqlite3] object pointer obtained |
325 | ** from [sqlite3_open()], [sqlite3_open16()], or |
326 | ** [sqlite3_open_v2()], and not previously closed. |
327 | ** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer |
328 | ** argument is a harmless no-op. |
329 | */ |
330 | SQLITE_API int sqlite3_close(sqlite3*); |
331 | SQLITE_API int sqlite3_close_v2(sqlite3*); |
332 | |
333 | /* |
334 | ** The type for a callback function. |
335 | ** This is legacy and deprecated. It is included for historical |
336 | ** compatibility and is not documented. |
337 | */ |
338 | typedef int (*sqlite3_callback)(void*,int,char**, char**); |
339 | |
340 | /* |
341 | ** CAPI3REF: One-Step Query Execution Interface |
342 | ** METHOD: sqlite3 |
343 | ** |
344 | ** The sqlite3_exec() interface is a convenience wrapper around |
345 | ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()], |
346 | ** that allows an application to run multiple statements of SQL |
347 | ** without having to use a lot of C code. |
348 | ** |
349 | ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded, |
350 | ** semicolon-separate SQL statements passed into its 2nd argument, |
351 | ** in the context of the [database connection] passed in as its 1st |
352 | ** argument. ^If the callback function of the 3rd argument to |
353 | ** sqlite3_exec() is not NULL, then it is invoked for each result row |
354 | ** coming out of the evaluated SQL statements. ^The 4th argument to |
355 | ** sqlite3_exec() is relayed through to the 1st argument of each |
356 | ** callback invocation. ^If the callback pointer to sqlite3_exec() |
357 | ** is NULL, then no callback is ever invoked and result rows are |
358 | ** ignored. |
359 | ** |
360 | ** ^If an error occurs while evaluating the SQL statements passed into |
361 | ** sqlite3_exec(), then execution of the current statement stops and |
362 | ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec() |
363 | ** is not NULL then any error message is written into memory obtained |
364 | ** from [sqlite3_malloc()] and passed back through the 5th parameter. |
365 | ** To avoid memory leaks, the application should invoke [sqlite3_free()] |
366 | ** on error message strings returned through the 5th parameter of |
367 | ** sqlite3_exec() after the error message string is no longer needed. |
368 | ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors |
369 | ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to |
370 | ** NULL before returning. |
371 | ** |
372 | ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec() |
373 | ** routine returns SQLITE_ABORT without invoking the callback again and |
374 | ** without running any subsequent SQL statements. |
375 | ** |
376 | ** ^The 2nd argument to the sqlite3_exec() callback function is the |
377 | ** number of columns in the result. ^The 3rd argument to the sqlite3_exec() |
378 | ** callback is an array of pointers to strings obtained as if from |
379 | ** [sqlite3_column_text()], one for each column. ^If an element of a |
380 | ** result row is NULL then the corresponding string pointer for the |
381 | ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the |
382 | ** sqlite3_exec() callback is an array of pointers to strings where each |
383 | ** entry represents the name of corresponding result column as obtained |
384 | ** from [sqlite3_column_name()]. |
385 | ** |
386 | ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer |
387 | ** to an empty string, or a pointer that contains only whitespace and/or |
388 | ** SQL comments, then no SQL statements are evaluated and the database |
389 | ** is not changed. |
390 | ** |
391 | ** Restrictions: |
392 | ** |
393 | ** <ul> |
394 | ** <li> The application must ensure that the 1st parameter to sqlite3_exec() |
395 | ** is a valid and open [database connection]. |
396 | ** <li> The application must not close the [database connection] specified by |
397 | ** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running. |
398 | ** <li> The application must not modify the SQL statement text passed into |
399 | ** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running. |
400 | ** </ul> |
401 | */ |
402 | SQLITE_API int sqlite3_exec( |
403 | sqlite3*, /* An open database */ |
404 | const char *sql, /* SQL to be evaluated */ |
405 | int (*callback)(void*,int,char**,char**), /* Callback function */ |
406 | void *, /* 1st argument to callback */ |
407 | char **errmsg /* Error msg written here */ |
408 | ); |
409 | |
410 | /* |
411 | ** CAPI3REF: Result Codes |
412 | ** KEYWORDS: {result code definitions} |
413 | ** |
414 | ** Many SQLite functions return an integer result code from the set shown |
415 | ** here in order to indicate success or failure. |
416 | ** |
417 | ** New error codes may be added in future versions of SQLite. |
418 | ** |
419 | ** See also: [extended result code definitions] |
420 | */ |
421 | #define SQLITE_OK 0 /* Successful result */ |
422 | /* beginning-of-error-codes */ |
423 | #define SQLITE_ERROR 1 /* Generic error */ |
424 | #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ |
425 | #define SQLITE_PERM 3 /* Access permission denied */ |
426 | #define SQLITE_ABORT 4 /* Callback routine requested an abort */ |
427 | #define SQLITE_BUSY 5 /* The database file is locked */ |
428 | #define SQLITE_LOCKED 6 /* A table in the database is locked */ |
429 | #define SQLITE_NOMEM 7 /* A malloc() failed */ |
430 | #define SQLITE_READONLY 8 /* Attempt to write a readonly database */ |
431 | #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ |
432 | #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ |
433 | #define SQLITE_CORRUPT 11 /* The database disk image is malformed */ |
434 | #define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */ |
435 | #define SQLITE_FULL 13 /* Insertion failed because database is full */ |
436 | #define SQLITE_CANTOPEN 14 /* Unable to open the database file */ |
437 | #define SQLITE_PROTOCOL 15 /* Database lock protocol error */ |
438 | #define SQLITE_EMPTY 16 /* Internal use only */ |
439 | #define SQLITE_SCHEMA 17 /* The database schema changed */ |
440 | #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ |
441 | #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ |
442 | #define SQLITE_MISMATCH 20 /* Data type mismatch */ |
443 | #define SQLITE_MISUSE 21 /* Library used incorrectly */ |
444 | #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ |
445 | #define SQLITE_AUTH 23 /* Authorization denied */ |
446 | #define SQLITE_FORMAT 24 /* Not used */ |
447 | #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ |
448 | #define SQLITE_NOTADB 26 /* File opened that is not a database file */ |
449 | #define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */ |
450 | #define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */ |
451 | #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ |
452 | #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ |
453 | /* end-of-error-codes */ |
454 | |
455 | /* |
456 | ** CAPI3REF: Extended Result Codes |
457 | ** KEYWORDS: {extended result code definitions} |
458 | ** |
459 | ** In its default configuration, SQLite API routines return one of 30 integer |
460 | ** [result codes]. However, experience has shown that many of |
461 | ** these result codes are too coarse-grained. They do not provide as |
462 | ** much information about problems as programmers might like. In an effort to |
463 | ** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8] |
464 | ** and later) include |
465 | ** support for additional result codes that provide more detailed information |
466 | ** about errors. These [extended result codes] are enabled or disabled |
467 | ** on a per database connection basis using the |
468 | ** [sqlite3_extended_result_codes()] API. Or, the extended code for |
469 | ** the most recent error can be obtained using |
470 | ** [sqlite3_extended_errcode()]. |
471 | */ |
472 | #define SQLITE_ERROR_MISSING_COLLSEQ (SQLITE_ERROR | (1<<8)) |
473 | #define SQLITE_ERROR_RETRY (SQLITE_ERROR | (2<<8)) |
474 | #define SQLITE_ERROR_SNAPSHOT (SQLITE_ERROR | (3<<8)) |
475 | #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) |
476 | #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) |
477 | #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) |
478 | #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) |
479 | #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) |
480 | #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) |
481 | #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) |
482 | #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) |
483 | #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) |
484 | #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) |
485 | #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) |
486 | #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) |
487 | #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) |
488 | #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) |
489 | #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) |
490 | #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8)) |
491 | #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8)) |
492 | #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8)) |
493 | #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8)) |
494 | #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8)) |
495 | #define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8)) |
496 | #define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8)) |
497 | #define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8)) |
498 | #define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8)) |
499 | #define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8)) |
500 | #define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8)) |
501 | #define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8)) |
502 | #define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8)) |
503 | #define SQLITE_IOERR_BEGIN_ATOMIC (SQLITE_IOERR | (29<<8)) |
504 | #define SQLITE_IOERR_COMMIT_ATOMIC (SQLITE_IOERR | (30<<8)) |
505 | #define SQLITE_IOERR_ROLLBACK_ATOMIC (SQLITE_IOERR | (31<<8)) |
506 | #define SQLITE_IOERR_DATA (SQLITE_IOERR | (32<<8)) |
507 | #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8)) |
508 | #define SQLITE_LOCKED_VTAB (SQLITE_LOCKED | (2<<8)) |
509 | #define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8)) |
510 | #define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8)) |
511 | #define SQLITE_BUSY_TIMEOUT (SQLITE_BUSY | (3<<8)) |
512 | #define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8)) |
513 | #define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8)) |
514 | #define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8)) |
515 | #define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8)) |
516 | #define SQLITE_CANTOPEN_DIRTYWAL (SQLITE_CANTOPEN | (5<<8)) /* Not Used */ |
517 | #define SQLITE_CANTOPEN_SYMLINK (SQLITE_CANTOPEN | (6<<8)) |
518 | #define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8)) |
519 | #define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8)) |
520 | #define SQLITE_CORRUPT_INDEX (SQLITE_CORRUPT | (3<<8)) |
521 | #define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8)) |
522 | #define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8)) |
523 | #define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8)) |
524 | #define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8)) |
525 | #define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8)) |
526 | #define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8)) |
527 | #define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8)) |
528 | #define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8)) |
529 | #define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8)) |
530 | #define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8)) |
531 | #define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8)) |
532 | #define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8)) |
533 | #define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8)) |
534 | #define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8)) |
535 | #define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8)) |
536 | #define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8)) |
537 | #define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8)) |
538 | #define SQLITE_CONSTRAINT_PINNED (SQLITE_CONSTRAINT |(11<<8)) |
539 | #define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8)) |
540 | #define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8)) |
541 | #define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8)) |
542 | #define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8)) |
543 | #define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8)) |
544 | #define SQLITE_OK_SYMLINK (SQLITE_OK | (2<<8)) |
545 | |
546 | /* |
547 | ** CAPI3REF: Flags For File Open Operations |
548 | ** |
549 | ** These bit values are intended for use in the |
550 | ** 3rd parameter to the [sqlite3_open_v2()] interface and |
551 | ** in the 4th parameter to the [sqlite3_vfs.xOpen] method. |
552 | */ |
553 | #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ |
554 | #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ |
555 | #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ |
556 | #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ |
557 | #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ |
558 | #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */ |
559 | #define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */ |
560 | #define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */ |
561 | #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ |
562 | #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ |
563 | #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ |
564 | #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ |
565 | #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ |
566 | #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ |
567 | #define SQLITE_OPEN_SUPER_JOURNAL 0x00004000 /* VFS only */ |
568 | #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ |
569 | #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ |
570 | #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ |
571 | #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ |
572 | #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */ |
573 | #define SQLITE_OPEN_NOFOLLOW 0x01000000 /* Ok for sqlite3_open_v2() */ |
574 | |
575 | /* Reserved: 0x00F00000 */ |
576 | /* Legacy compatibility: */ |
577 | #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ |
578 | |
579 | |
580 | /* |
581 | ** CAPI3REF: Device Characteristics |
582 | ** |
583 | ** The xDeviceCharacteristics method of the [sqlite3_io_methods] |
584 | ** object returns an integer which is a vector of these |
585 | ** bit values expressing I/O characteristics of the mass storage |
586 | ** device that holds the file that the [sqlite3_io_methods] |
587 | ** refers to. |
588 | ** |
589 | ** The SQLITE_IOCAP_ATOMIC property means that all writes of |
590 | ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values |
591 | ** mean that writes of blocks that are nnn bytes in size and |
592 | ** are aligned to an address which is an integer multiple of |
593 | ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means |
594 | ** that when data is appended to a file, the data is appended |
595 | ** first then the size of the file is extended, never the other |
596 | ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that |
597 | ** information is written to disk in the same order as calls |
598 | ** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that |
599 | ** after reboot following a crash or power loss, the only bytes in a |
600 | ** file that were written at the application level might have changed |
601 | ** and that adjacent bytes, even bytes within the same sector are |
602 | ** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN |
603 | ** flag indicates that a file cannot be deleted when open. The |
604 | ** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on |
605 | ** read-only media and cannot be changed even by processes with |
606 | ** elevated privileges. |
607 | ** |
608 | ** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying |
609 | ** filesystem supports doing multiple write operations atomically when those |
610 | ** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and |
611 | ** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. |
612 | */ |
613 | #define SQLITE_IOCAP_ATOMIC 0x00000001 |
614 | #define SQLITE_IOCAP_ATOMIC512 0x00000002 |
615 | #define SQLITE_IOCAP_ATOMIC1K 0x00000004 |
616 | #define SQLITE_IOCAP_ATOMIC2K 0x00000008 |
617 | #define SQLITE_IOCAP_ATOMIC4K 0x00000010 |
618 | #define SQLITE_IOCAP_ATOMIC8K 0x00000020 |
619 | #define SQLITE_IOCAP_ATOMIC16K 0x00000040 |
620 | #define SQLITE_IOCAP_ATOMIC32K 0x00000080 |
621 | #define SQLITE_IOCAP_ATOMIC64K 0x00000100 |
622 | #define SQLITE_IOCAP_SAFE_APPEND 0x00000200 |
623 | #define SQLITE_IOCAP_SEQUENTIAL 0x00000400 |
624 | #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800 |
625 | #define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000 |
626 | #define SQLITE_IOCAP_IMMUTABLE 0x00002000 |
627 | #define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000 |
628 | |
629 | /* |
630 | ** CAPI3REF: File Locking Levels |
631 | ** |
632 | ** SQLite uses one of these integer values as the second |
633 | ** argument to calls it makes to the xLock() and xUnlock() methods |
634 | ** of an [sqlite3_io_methods] object. |
635 | */ |
636 | #define SQLITE_LOCK_NONE 0 |
637 | #define SQLITE_LOCK_SHARED 1 |
638 | #define SQLITE_LOCK_RESERVED 2 |
639 | #define SQLITE_LOCK_PENDING 3 |
640 | #define SQLITE_LOCK_EXCLUSIVE 4 |
641 | |
642 | /* |
643 | ** CAPI3REF: Synchronization Type Flags |
644 | ** |
645 | ** When SQLite invokes the xSync() method of an |
646 | ** [sqlite3_io_methods] object it uses a combination of |
647 | ** these integer values as the second argument. |
648 | ** |
649 | ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the |
650 | ** sync operation only needs to flush data to mass storage. Inode |
651 | ** information need not be flushed. If the lower four bits of the flag |
652 | ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. |
653 | ** If the lower four bits equal SQLITE_SYNC_FULL, that means |
654 | ** to use Mac OS X style fullsync instead of fsync(). |
655 | ** |
656 | ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags |
657 | ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL |
658 | ** settings. The [synchronous pragma] determines when calls to the |
659 | ** xSync VFS method occur and applies uniformly across all platforms. |
660 | ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how |
661 | ** energetic or rigorous or forceful the sync operations are and |
662 | ** only make a difference on Mac OSX for the default SQLite code. |
663 | ** (Third-party VFS implementations might also make the distinction |
664 | ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the |
665 | ** operating systems natively supported by SQLite, only Mac OSX |
666 | ** cares about the difference.) |
667 | */ |
668 | #define SQLITE_SYNC_NORMAL 0x00002 |
669 | #define SQLITE_SYNC_FULL 0x00003 |
670 | #define SQLITE_SYNC_DATAONLY 0x00010 |
671 | |
672 | /* |
673 | ** CAPI3REF: OS Interface Open File Handle |
674 | ** |
675 | ** An [sqlite3_file] object represents an open file in the |
676 | ** [sqlite3_vfs | OS interface layer]. Individual OS interface |
677 | ** implementations will |
678 | ** want to subclass this object by appending additional fields |
679 | ** for their own use. The pMethods entry is a pointer to an |
680 | ** [sqlite3_io_methods] object that defines methods for performing |
681 | ** I/O operations on the open file. |
682 | */ |
683 | typedef struct sqlite3_file sqlite3_file; |
684 | struct sqlite3_file { |
685 | const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ |
686 | }; |
687 | |
688 | /* |
689 | ** CAPI3REF: OS Interface File Virtual Methods Object |
690 | ** |
691 | ** Every file opened by the [sqlite3_vfs.xOpen] method populates an |
692 | ** [sqlite3_file] object (or, more commonly, a subclass of the |
693 | ** [sqlite3_file] object) with a pointer to an instance of this object. |
694 | ** This object defines the methods used to perform various operations |
695 | ** against the open file represented by the [sqlite3_file] object. |
696 | ** |
697 | ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element |
698 | ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method |
699 | ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The |
700 | ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen] |
701 | ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element |
702 | ** to NULL. |
703 | ** |
704 | ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or |
705 | ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). |
706 | ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] |
707 | ** flag may be ORed in to indicate that only the data of the file |
708 | ** and not its inode needs to be synced. |
709 | ** |
710 | ** The integer values to xLock() and xUnlock() are one of |
711 | ** <ul> |
712 | ** <li> [SQLITE_LOCK_NONE], |
713 | ** <li> [SQLITE_LOCK_SHARED], |
714 | ** <li> [SQLITE_LOCK_RESERVED], |
715 | ** <li> [SQLITE_LOCK_PENDING], or |
716 | ** <li> [SQLITE_LOCK_EXCLUSIVE]. |
717 | ** </ul> |
718 | ** xLock() increases the lock. xUnlock() decreases the lock. |
719 | ** The xCheckReservedLock() method checks whether any database connection, |
720 | ** either in this process or in some other process, is holding a RESERVED, |
721 | ** PENDING, or EXCLUSIVE lock on the file. It returns true |
722 | ** if such a lock exists and false otherwise. |
723 | ** |
724 | ** The xFileControl() method is a generic interface that allows custom |
725 | ** VFS implementations to directly control an open file using the |
726 | ** [sqlite3_file_control()] interface. The second "op" argument is an |
727 | ** integer opcode. The third argument is a generic pointer intended to |
728 | ** point to a structure that may contain arguments or space in which to |
729 | ** write return values. Potential uses for xFileControl() might be |
730 | ** functions to enable blocking locks with timeouts, to change the |
731 | ** locking strategy (for example to use dot-file locks), to inquire |
732 | ** about the status of a lock, or to break stale locks. The SQLite |
733 | ** core reserves all opcodes less than 100 for its own use. |
734 | ** A [file control opcodes | list of opcodes] less than 100 is available. |
735 | ** Applications that define a custom xFileControl method should use opcodes |
736 | ** greater than 100 to avoid conflicts. VFS implementations should |
737 | ** return [SQLITE_NOTFOUND] for file control opcodes that they do not |
738 | ** recognize. |
739 | ** |
740 | ** The xSectorSize() method returns the sector size of the |
741 | ** device that underlies the file. The sector size is the |
742 | ** minimum write that can be performed without disturbing |
743 | ** other bytes in the file. The xDeviceCharacteristics() |
744 | ** method returns a bit vector describing behaviors of the |
745 | ** underlying device: |
746 | ** |
747 | ** <ul> |
748 | ** <li> [SQLITE_IOCAP_ATOMIC] |
749 | ** <li> [SQLITE_IOCAP_ATOMIC512] |
750 | ** <li> [SQLITE_IOCAP_ATOMIC1K] |
751 | ** <li> [SQLITE_IOCAP_ATOMIC2K] |
752 | ** <li> [SQLITE_IOCAP_ATOMIC4K] |
753 | ** <li> [SQLITE_IOCAP_ATOMIC8K] |
754 | ** <li> [SQLITE_IOCAP_ATOMIC16K] |
755 | ** <li> [SQLITE_IOCAP_ATOMIC32K] |
756 | ** <li> [SQLITE_IOCAP_ATOMIC64K] |
757 | ** <li> [SQLITE_IOCAP_SAFE_APPEND] |
758 | ** <li> [SQLITE_IOCAP_SEQUENTIAL] |
759 | ** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN] |
760 | ** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE] |
761 | ** <li> [SQLITE_IOCAP_IMMUTABLE] |
762 | ** <li> [SQLITE_IOCAP_BATCH_ATOMIC] |
763 | ** </ul> |
764 | ** |
765 | ** The SQLITE_IOCAP_ATOMIC property means that all writes of |
766 | ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values |
767 | ** mean that writes of blocks that are nnn bytes in size and |
768 | ** are aligned to an address which is an integer multiple of |
769 | ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means |
770 | ** that when data is appended to a file, the data is appended |
771 | ** first then the size of the file is extended, never the other |
772 | ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that |
773 | ** information is written to disk in the same order as calls |
774 | ** to xWrite(). |
775 | ** |
776 | ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill |
777 | ** in the unread portions of the buffer with zeros. A VFS that |
778 | ** fails to zero-fill short reads might seem to work. However, |
779 | ** failure to zero-fill short reads will eventually lead to |
780 | ** database corruption. |
781 | */ |
782 | typedef struct sqlite3_io_methods sqlite3_io_methods; |
783 | struct sqlite3_io_methods { |
784 | int iVersion; |
785 | int (*xClose)(sqlite3_file*); |
786 | int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); |
787 | int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); |
788 | int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); |
789 | int (*xSync)(sqlite3_file*, int flags); |
790 | int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); |
791 | int (*xLock)(sqlite3_file*, int); |
792 | int (*xUnlock)(sqlite3_file*, int); |
793 | int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); |
794 | int (*xFileControl)(sqlite3_file*, int op, void *pArg); |
795 | int (*xSectorSize)(sqlite3_file*); |
796 | int (*xDeviceCharacteristics)(sqlite3_file*); |
797 | /* Methods above are valid for version 1 */ |
798 | int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**); |
799 | int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); |
800 | void (*xShmBarrier)(sqlite3_file*); |
801 | int (*xShmUnmap)(sqlite3_file*, int deleteFlag); |
802 | /* Methods above are valid for version 2 */ |
803 | int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp); |
804 | int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p); |
805 | /* Methods above are valid for version 3 */ |
806 | /* Additional methods may be added in future releases */ |
807 | }; |
808 | |
809 | /* |
810 | ** CAPI3REF: Standard File Control Opcodes |
811 | ** KEYWORDS: {file control opcodes} {file control opcode} |
812 | ** |
813 | ** These integer constants are opcodes for the xFileControl method |
814 | ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] |
815 | ** interface. |
816 | ** |
817 | ** <ul> |
818 | ** <li>[[SQLITE_FCNTL_LOCKSTATE]] |
819 | ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This |
820 | ** opcode causes the xFileControl method to write the current state of |
821 | ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], |
822 | ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) |
823 | ** into an integer that the pArg argument points to. This capability |
824 | ** is used during testing and is only available when the SQLITE_TEST |
825 | ** compile-time option is used. |
826 | ** |
827 | ** <li>[[SQLITE_FCNTL_SIZE_HINT]] |
828 | ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS |
829 | ** layer a hint of how large the database file will grow to be during the |
830 | ** current transaction. This hint is not guaranteed to be accurate but it |
831 | ** is often close. The underlying VFS might choose to preallocate database |
832 | ** file space based on this hint in order to help writes to the database |
833 | ** file run faster. |
834 | ** |
835 | ** <li>[[SQLITE_FCNTL_SIZE_LIMIT]] |
836 | ** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that |
837 | ** implements [sqlite3_deserialize()] to set an upper bound on the size |
838 | ** of the in-memory database. The argument is a pointer to a [sqlite3_int64]. |
839 | ** If the integer pointed to is negative, then it is filled in with the |
840 | ** current limit. Otherwise the limit is set to the larger of the value |
841 | ** of the integer pointed to and the current database size. The integer |
842 | ** pointed to is set to the new limit. |
843 | ** |
844 | ** <li>[[SQLITE_FCNTL_CHUNK_SIZE]] |
845 | ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS |
846 | ** extends and truncates the database file in chunks of a size specified |
847 | ** by the user. The fourth argument to [sqlite3_file_control()] should |
848 | ** point to an integer (type int) containing the new chunk-size to use |
849 | ** for the nominated database. Allocating database file space in large |
850 | ** chunks (say 1MB at a time), may reduce file-system fragmentation and |
851 | ** improve performance on some systems. |
852 | ** |
853 | ** <li>[[SQLITE_FCNTL_FILE_POINTER]] |
854 | ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer |
855 | ** to the [sqlite3_file] object associated with a particular database |
856 | ** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER]. |
857 | ** |
858 | ** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]] |
859 | ** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer |
860 | ** to the [sqlite3_file] object associated with the journal file (either |
861 | ** the [rollback journal] or the [write-ahead log]) for a particular database |
862 | ** connection. See also [SQLITE_FCNTL_FILE_POINTER]. |
863 | ** |
864 | ** <li>[[SQLITE_FCNTL_SYNC_OMITTED]] |
865 | ** No longer in use. |
866 | ** |
867 | ** <li>[[SQLITE_FCNTL_SYNC]] |
868 | ** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and |
869 | ** sent to the VFS immediately before the xSync method is invoked on a |
870 | ** database file descriptor. Or, if the xSync method is not invoked |
871 | ** because the user has configured SQLite with |
872 | ** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place |
873 | ** of the xSync method. In most cases, the pointer argument passed with |
874 | ** this file-control is NULL. However, if the database file is being synced |
875 | ** as part of a multi-database commit, the argument points to a nul-terminated |
876 | ** string containing the transactions super-journal file name. VFSes that |
877 | ** do not need this signal should silently ignore this opcode. Applications |
878 | ** should not call [sqlite3_file_control()] with this opcode as doing so may |
879 | ** disrupt the operation of the specialized VFSes that do require it. |
880 | ** |
881 | ** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]] |
882 | ** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite |
883 | ** and sent to the VFS after a transaction has been committed immediately |
884 | ** but before the database is unlocked. VFSes that do not need this signal |
885 | ** should silently ignore this opcode. Applications should not call |
886 | ** [sqlite3_file_control()] with this opcode as doing so may disrupt the |
887 | ** operation of the specialized VFSes that do require it. |
888 | ** |
889 | ** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]] |
890 | ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic |
891 | ** retry counts and intervals for certain disk I/O operations for the |
892 | ** windows [VFS] in order to provide robustness in the presence of |
893 | ** anti-virus programs. By default, the windows VFS will retry file read, |
894 | ** file write, and file delete operations up to 10 times, with a delay |
895 | ** of 25 milliseconds before the first retry and with the delay increasing |
896 | ** by an additional 25 milliseconds with each subsequent retry. This |
897 | ** opcode allows these two values (10 retries and 25 milliseconds of delay) |
898 | ** to be adjusted. The values are changed for all database connections |
899 | ** within the same process. The argument is a pointer to an array of two |
900 | ** integers where the first integer is the new retry count and the second |
901 | ** integer is the delay. If either integer is negative, then the setting |
902 | ** is not changed but instead the prior value of that setting is written |
903 | ** into the array entry, allowing the current retry settings to be |
904 | ** interrogated. The zDbName parameter is ignored. |
905 | ** |
906 | ** <li>[[SQLITE_FCNTL_PERSIST_WAL]] |
907 | ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the |
908 | ** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary |
909 | ** write ahead log ([WAL file]) and shared memory |
910 | ** files used for transaction control |
911 | ** are automatically deleted when the latest connection to the database |
912 | ** closes. Setting persistent WAL mode causes those files to persist after |
913 | ** close. Persisting the files is useful when other processes that do not |
914 | ** have write permission on the directory containing the database file want |
915 | ** to read the database file, as the WAL and shared memory files must exist |
916 | ** in order for the database to be readable. The fourth parameter to |
917 | ** [sqlite3_file_control()] for this opcode should be a pointer to an integer. |
918 | ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent |
919 | ** WAL mode. If the integer is -1, then it is overwritten with the current |
920 | ** WAL persistence setting. |
921 | ** |
922 | ** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]] |
923 | ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the |
924 | ** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting |
925 | ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the |
926 | ** xDeviceCharacteristics methods. The fourth parameter to |
927 | ** [sqlite3_file_control()] for this opcode should be a pointer to an integer. |
928 | ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage |
929 | ** mode. If the integer is -1, then it is overwritten with the current |
930 | ** zero-damage mode setting. |
931 | ** |
932 | ** <li>[[SQLITE_FCNTL_OVERWRITE]] |
933 | ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening |
934 | ** a write transaction to indicate that, unless it is rolled back for some |
935 | ** reason, the entire database file will be overwritten by the current |
936 | ** transaction. This is used by VACUUM operations. |
937 | ** |
938 | ** <li>[[SQLITE_FCNTL_VFSNAME]] |
939 | ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of |
940 | ** all [VFSes] in the VFS stack. The names are of all VFS shims and the |
941 | ** final bottom-level VFS are written into memory obtained from |
942 | ** [sqlite3_malloc()] and the result is stored in the char* variable |
943 | ** that the fourth parameter of [sqlite3_file_control()] points to. |
944 | ** The caller is responsible for freeing the memory when done. As with |
945 | ** all file-control actions, there is no guarantee that this will actually |
946 | ** do anything. Callers should initialize the char* variable to a NULL |
947 | ** pointer in case this file-control is not implemented. This file-control |
948 | ** is intended for diagnostic use only. |
949 | ** |
950 | ** <li>[[SQLITE_FCNTL_VFS_POINTER]] |
951 | ** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level |
952 | ** [VFSes] currently in use. ^(The argument X in |
953 | ** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be |
954 | ** of type "[sqlite3_vfs] **". This opcodes will set *X |
955 | ** to a pointer to the top-level VFS.)^ |
956 | ** ^When there are multiple VFS shims in the stack, this opcode finds the |
957 | ** upper-most shim only. |
958 | ** |
959 | ** <li>[[SQLITE_FCNTL_PRAGMA]] |
960 | ** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] |
961 | ** file control is sent to the open [sqlite3_file] object corresponding |
962 | ** to the database file to which the pragma statement refers. ^The argument |
963 | ** to the [SQLITE_FCNTL_PRAGMA] file control is an array of |
964 | ** pointers to strings (char**) in which the second element of the array |
965 | ** is the name of the pragma and the third element is the argument to the |
966 | ** pragma or NULL if the pragma has no argument. ^The handler for an |
967 | ** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element |
968 | ** of the char** argument point to a string obtained from [sqlite3_mprintf()] |
969 | ** or the equivalent and that string will become the result of the pragma or |
970 | ** the error message if the pragma fails. ^If the |
971 | ** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal |
972 | ** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA] |
973 | ** file control returns [SQLITE_OK], then the parser assumes that the |
974 | ** VFS has handled the PRAGMA itself and the parser generates a no-op |
975 | ** prepared statement if result string is NULL, or that returns a copy |
976 | ** of the result string if the string is non-NULL. |
977 | ** ^If the [SQLITE_FCNTL_PRAGMA] file control returns |
978 | ** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means |
979 | ** that the VFS encountered an error while handling the [PRAGMA] and the |
980 | ** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA] |
981 | ** file control occurs at the beginning of pragma statement analysis and so |
982 | ** it is able to override built-in [PRAGMA] statements. |
983 | ** |
984 | ** <li>[[SQLITE_FCNTL_BUSYHANDLER]] |
985 | ** ^The [SQLITE_FCNTL_BUSYHANDLER] |
986 | ** file-control may be invoked by SQLite on the database file handle |
987 | ** shortly after it is opened in order to provide a custom VFS with access |
988 | ** to the connection's busy-handler callback. The argument is of type (void**) |
989 | ** - an array of two (void *) values. The first (void *) actually points |
990 | ** to a function of type (int (*)(void *)). In order to invoke the connection's |
991 | ** busy-handler, this function should be invoked with the second (void *) in |
992 | ** the array as the only argument. If it returns non-zero, then the operation |
993 | ** should be retried. If it returns zero, the custom VFS should abandon the |
994 | ** current operation. |
995 | ** |
996 | ** <li>[[SQLITE_FCNTL_TEMPFILENAME]] |
997 | ** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control |
998 | ** to have SQLite generate a |
999 | ** temporary filename using the same algorithm that is followed to generate |
1000 | ** temporary filenames for TEMP tables and other internal uses. The |
1001 | ** argument should be a char** which will be filled with the filename |
1002 | ** written into memory obtained from [sqlite3_malloc()]. The caller should |
1003 | ** invoke [sqlite3_free()] on the result to avoid a memory leak. |
1004 | ** |
1005 | ** <li>[[SQLITE_FCNTL_MMAP_SIZE]] |
1006 | ** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the |
1007 | ** maximum number of bytes that will be used for memory-mapped I/O. |
1008 | ** The argument is a pointer to a value of type sqlite3_int64 that |
1009 | ** is an advisory maximum number of bytes in the file to memory map. The |
1010 | ** pointer is overwritten with the old value. The limit is not changed if |
1011 | ** the value originally pointed to is negative, and so the current limit |
1012 | ** can be queried by passing in a pointer to a negative number. This |
1013 | ** file-control is used internally to implement [PRAGMA mmap_size]. |
1014 | ** |
1015 | ** <li>[[SQLITE_FCNTL_TRACE]] |
1016 | ** The [SQLITE_FCNTL_TRACE] file control provides advisory information |
1017 | ** to the VFS about what the higher layers of the SQLite stack are doing. |
1018 | ** This file control is used by some VFS activity tracing [shims]. |
1019 | ** The argument is a zero-terminated string. Higher layers in the |
1020 | ** SQLite stack may generate instances of this file control if |
1021 | ** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled. |
1022 | ** |
1023 | ** <li>[[SQLITE_FCNTL_HAS_MOVED]] |
1024 | ** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a |
1025 | ** pointer to an integer and it writes a boolean into that integer depending |
1026 | ** on whether or not the file has been renamed, moved, or deleted since it |
1027 | ** was first opened. |
1028 | ** |
1029 | ** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]] |
1030 | ** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the |
1031 | ** underlying native file handle associated with a file handle. This file |
1032 | ** control interprets its argument as a pointer to a native file handle and |
1033 | ** writes the resulting value there. |
1034 | ** |
1035 | ** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]] |
1036 | ** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This |
1037 | ** opcode causes the xFileControl method to swap the file handle with the one |
1038 | ** pointed to by the pArg argument. This capability is used during testing |
1039 | ** and only needs to be supported when SQLITE_TEST is defined. |
1040 | ** |
1041 | ** <li>[[SQLITE_FCNTL_WAL_BLOCK]] |
1042 | ** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might |
1043 | ** be advantageous to block on the next WAL lock if the lock is not immediately |
1044 | ** available. The WAL subsystem issues this signal during rare |
1045 | ** circumstances in order to fix a problem with priority inversion. |
1046 | ** Applications should <em>not</em> use this file-control. |
1047 | ** |
1048 | ** <li>[[SQLITE_FCNTL_ZIPVFS]] |
1049 | ** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other |
1050 | ** VFS should return SQLITE_NOTFOUND for this opcode. |
1051 | ** |
1052 | ** <li>[[SQLITE_FCNTL_RBU]] |
1053 | ** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by |
1054 | ** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for |
1055 | ** this opcode. |
1056 | ** |
1057 | ** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]] |
1058 | ** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then |
1059 | ** the file descriptor is placed in "batch write mode", which |
1060 | ** means all subsequent write operations will be deferred and done |
1061 | ** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. Systems |
1062 | ** that do not support batch atomic writes will return SQLITE_NOTFOUND. |
1063 | ** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to |
1064 | ** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or |
1065 | ** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make |
1066 | ** no VFS interface calls on the same [sqlite3_file] file descriptor |
1067 | ** except for calls to the xWrite method and the xFileControl method |
1068 | ** with [SQLITE_FCNTL_SIZE_HINT]. |
1069 | ** |
1070 | ** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]] |
1071 | ** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write |
1072 | ** operations since the previous successful call to |
1073 | ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically. |
1074 | ** This file control returns [SQLITE_OK] if and only if the writes were |
1075 | ** all performed successfully and have been committed to persistent storage. |
1076 | ** ^Regardless of whether or not it is successful, this file control takes |
1077 | ** the file descriptor out of batch write mode so that all subsequent |
1078 | ** write operations are independent. |
1079 | ** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without |
1080 | ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. |
1081 | ** |
1082 | ** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]] |
1083 | ** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write |
1084 | ** operations since the previous successful call to |
1085 | ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back. |
1086 | ** ^This file control takes the file descriptor out of batch write mode |
1087 | ** so that all subsequent write operations are independent. |
1088 | ** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without |
1089 | ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. |
1090 | ** |
1091 | ** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]] |
1092 | ** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS |
1093 | ** to block for up to M milliseconds before failing when attempting to |
1094 | ** obtain a file lock using the xLock or xShmLock methods of the VFS. |
1095 | ** The parameter is a pointer to a 32-bit signed integer that contains |
1096 | ** the value that M is to be set to. Before returning, the 32-bit signed |
1097 | ** integer is overwritten with the previous value of M. |
1098 | ** |
1099 | ** <li>[[SQLITE_FCNTL_DATA_VERSION]] |
1100 | ** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to |
1101 | ** a database file. The argument is a pointer to a 32-bit unsigned integer. |
1102 | ** The "data version" for the pager is written into the pointer. The |
1103 | ** "data version" changes whenever any change occurs to the corresponding |
1104 | ** database file, either through SQL statements on the same database |
1105 | ** connection or through transactions committed by separate database |
1106 | ** connections possibly in other processes. The [sqlite3_total_changes()] |
1107 | ** interface can be used to find if any database on the connection has changed, |
1108 | ** but that interface responds to changes on TEMP as well as MAIN and does |
1109 | ** not provide a mechanism to detect changes to MAIN only. Also, the |
1110 | ** [sqlite3_total_changes()] interface responds to internal changes only and |
1111 | ** omits changes made by other database connections. The |
1112 | ** [PRAGMA data_version] command provides a mechanism to detect changes to |
1113 | ** a single attached database that occur due to other database connections, |
1114 | ** but omits changes implemented by the database connection on which it is |
1115 | ** called. This file control is the only mechanism to detect changes that |
1116 | ** happen either internally or externally and that are associated with |
1117 | ** a particular attached database. |
1118 | ** |
1119 | ** <li>[[SQLITE_FCNTL_CKPT_START]] |
1120 | ** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint |
1121 | ** in wal mode before the client starts to copy pages from the wal |
1122 | ** file to the database file. |
1123 | ** |
1124 | ** <li>[[SQLITE_FCNTL_CKPT_DONE]] |
1125 | ** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint |
1126 | ** in wal mode after the client has finished copying pages from the wal |
1127 | ** file to the database file, but before the *-shm file is updated to |
1128 | ** record the fact that the pages have been checkpointed. |
1129 | ** </ul> |
1130 | */ |
1131 | #define SQLITE_FCNTL_LOCKSTATE 1 |
1132 | #define SQLITE_FCNTL_GET_LOCKPROXYFILE 2 |
1133 | #define SQLITE_FCNTL_SET_LOCKPROXYFILE 3 |
1134 | #define SQLITE_FCNTL_LAST_ERRNO 4 |
1135 | #define SQLITE_FCNTL_SIZE_HINT 5 |
1136 | #define SQLITE_FCNTL_CHUNK_SIZE 6 |
1137 | #define SQLITE_FCNTL_FILE_POINTER 7 |
1138 | #define SQLITE_FCNTL_SYNC_OMITTED 8 |
1139 | #define SQLITE_FCNTL_WIN32_AV_RETRY 9 |
1140 | #define SQLITE_FCNTL_PERSIST_WAL 10 |
1141 | #define SQLITE_FCNTL_OVERWRITE 11 |
1142 | #define SQLITE_FCNTL_VFSNAME 12 |
1143 | #define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13 |
1144 | #define SQLITE_FCNTL_PRAGMA 14 |
1145 | #define SQLITE_FCNTL_BUSYHANDLER 15 |
1146 | #define SQLITE_FCNTL_TEMPFILENAME 16 |
1147 | #define SQLITE_FCNTL_MMAP_SIZE 18 |
1148 | #define SQLITE_FCNTL_TRACE 19 |
1149 | #define SQLITE_FCNTL_HAS_MOVED 20 |
1150 | #define SQLITE_FCNTL_SYNC 21 |
1151 | #define SQLITE_FCNTL_COMMIT_PHASETWO 22 |
1152 | #define SQLITE_FCNTL_WIN32_SET_HANDLE 23 |
1153 | #define SQLITE_FCNTL_WAL_BLOCK 24 |
1154 | #define SQLITE_FCNTL_ZIPVFS 25 |
1155 | #define SQLITE_FCNTL_RBU 26 |
1156 | #define SQLITE_FCNTL_VFS_POINTER 27 |
1157 | #define SQLITE_FCNTL_JOURNAL_POINTER 28 |
1158 | #define SQLITE_FCNTL_WIN32_GET_HANDLE 29 |
1159 | #define SQLITE_FCNTL_PDB 30 |
1160 | #define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31 |
1161 | #define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32 |
1162 | #define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33 |
1163 | #define SQLITE_FCNTL_LOCK_TIMEOUT 34 |
1164 | #define SQLITE_FCNTL_DATA_VERSION 35 |
1165 | #define SQLITE_FCNTL_SIZE_LIMIT 36 |
1166 | #define SQLITE_FCNTL_CKPT_DONE 37 |
1167 | #define SQLITE_FCNTL_RESERVE_BYTES 38 |
1168 | #define SQLITE_FCNTL_CKPT_START 39 |
1169 | |
1170 | /* deprecated names */ |
1171 | #define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE |
1172 | #define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE |
1173 | #define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO |
1174 | |
1175 | |
1176 | /* |
1177 | ** CAPI3REF: Mutex Handle |
1178 | ** |
1179 | ** The mutex module within SQLite defines [sqlite3_mutex] to be an |
1180 | ** abstract type for a mutex object. The SQLite core never looks |
1181 | ** at the internal representation of an [sqlite3_mutex]. It only |
1182 | ** deals with pointers to the [sqlite3_mutex] object. |
1183 | ** |
1184 | ** Mutexes are created using [sqlite3_mutex_alloc()]. |
1185 | */ |
1186 | typedef struct sqlite3_mutex sqlite3_mutex; |
1187 | |
1188 | /* |
1189 | ** CAPI3REF: Loadable Extension Thunk |
1190 | ** |
1191 | ** A pointer to the opaque sqlite3_api_routines structure is passed as |
1192 | ** the third parameter to entry points of [loadable extensions]. This |
1193 | ** structure must be typedefed in order to work around compiler warnings |
1194 | ** on some platforms. |
1195 | */ |
1196 | typedef struct sqlite3_api_routines sqlite3_api_routines; |
1197 | |
1198 | /* |
1199 | ** CAPI3REF: OS Interface Object |
1200 | ** |
1201 | ** An instance of the sqlite3_vfs object defines the interface between |
1202 | ** the SQLite core and the underlying operating system. The "vfs" |
1203 | ** in the name of the object stands for "virtual file system". See |
1204 | ** the [VFS | VFS documentation] for further information. |
1205 | ** |
1206 | ** The VFS interface is sometimes extended by adding new methods onto |
1207 | ** the end. Each time such an extension occurs, the iVersion field |
1208 | ** is incremented. The iVersion value started out as 1 in |
1209 | ** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2 |
1210 | ** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased |
1211 | ** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields |
1212 | ** may be appended to the sqlite3_vfs object and the iVersion value |
1213 | ** may increase again in future versions of SQLite. |
1214 | ** Note that due to an oversight, the structure |
1215 | ** of the sqlite3_vfs object changed in the transition from |
1216 | ** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0] |
1217 | ** and yet the iVersion field was not increased. |
1218 | ** |
1219 | ** The szOsFile field is the size of the subclassed [sqlite3_file] |
1220 | ** structure used by this VFS. mxPathname is the maximum length of |
1221 | ** a pathname in this VFS. |
1222 | ** |
1223 | ** Registered sqlite3_vfs objects are kept on a linked list formed by |
1224 | ** the pNext pointer. The [sqlite3_vfs_register()] |
1225 | ** and [sqlite3_vfs_unregister()] interfaces manage this list |
1226 | ** in a thread-safe way. The [sqlite3_vfs_find()] interface |
1227 | ** searches the list. Neither the application code nor the VFS |
1228 | ** implementation should use the pNext pointer. |
1229 | ** |
1230 | ** The pNext field is the only field in the sqlite3_vfs |
1231 | ** structure that SQLite will ever modify. SQLite will only access |
1232 | ** or modify this field while holding a particular static mutex. |
1233 | ** The application should never modify anything within the sqlite3_vfs |
1234 | ** object once the object has been registered. |
1235 | ** |
1236 | ** The zName field holds the name of the VFS module. The name must |
1237 | ** be unique across all VFS modules. |
1238 | ** |
1239 | ** [[sqlite3_vfs.xOpen]] |
1240 | ** ^SQLite guarantees that the zFilename parameter to xOpen |
1241 | ** is either a NULL pointer or string obtained |
1242 | ** from xFullPathname() with an optional suffix added. |
1243 | ** ^If a suffix is added to the zFilename parameter, it will |
1244 | ** consist of a single "-" character followed by no more than |
1245 | ** 11 alphanumeric and/or "-" characters. |
1246 | ** ^SQLite further guarantees that |
1247 | ** the string will be valid and unchanged until xClose() is |
1248 | ** called. Because of the previous sentence, |
1249 | ** the [sqlite3_file] can safely store a pointer to the |
1250 | ** filename if it needs to remember the filename for some reason. |
1251 | ** If the zFilename parameter to xOpen is a NULL pointer then xOpen |
1252 | ** must invent its own temporary name for the file. ^Whenever the |
1253 | ** xFilename parameter is NULL it will also be the case that the |
1254 | ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. |
1255 | ** |
1256 | ** The flags argument to xOpen() includes all bits set in |
1257 | ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] |
1258 | ** or [sqlite3_open16()] is used, then flags includes at least |
1259 | ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. |
1260 | ** If xOpen() opens a file read-only then it sets *pOutFlags to |
1261 | ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. |
1262 | ** |
1263 | ** ^(SQLite will also add one of the following flags to the xOpen() |
1264 | ** call, depending on the object being opened: |
1265 | ** |
1266 | ** <ul> |
1267 | ** <li> [SQLITE_OPEN_MAIN_DB] |
1268 | ** <li> [SQLITE_OPEN_MAIN_JOURNAL] |
1269 | ** <li> [SQLITE_OPEN_TEMP_DB] |
1270 | ** <li> [SQLITE_OPEN_TEMP_JOURNAL] |
1271 | ** <li> [SQLITE_OPEN_TRANSIENT_DB] |
1272 | ** <li> [SQLITE_OPEN_SUBJOURNAL] |
1273 | ** <li> [SQLITE_OPEN_SUPER_JOURNAL] |
1274 | ** <li> [SQLITE_OPEN_WAL] |
1275 | ** </ul>)^ |
1276 | ** |
1277 | ** The file I/O implementation can use the object type flags to |
1278 | ** change the way it deals with files. For example, an application |
1279 | ** that does not care about crash recovery or rollback might make |
1280 | ** the open of a journal file a no-op. Writes to this journal would |
1281 | ** also be no-ops, and any attempt to read the journal would return |
1282 | ** SQLITE_IOERR. Or the implementation might recognize that a database |
1283 | ** file will be doing page-aligned sector reads and writes in a random |
1284 | ** order and set up its I/O subsystem accordingly. |
1285 | ** |
1286 | ** SQLite might also add one of the following flags to the xOpen method: |
1287 | ** |
1288 | ** <ul> |
1289 | ** <li> [SQLITE_OPEN_DELETEONCLOSE] |
1290 | ** <li> [SQLITE_OPEN_EXCLUSIVE] |
1291 | ** </ul> |
1292 | ** |
1293 | ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be |
1294 | ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] |
1295 | ** will be set for TEMP databases and their journals, transient |
1296 | ** databases, and subjournals. |
1297 | ** |
1298 | ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction |
1299 | ** with the [SQLITE_OPEN_CREATE] flag, which are both directly |
1300 | ** analogous to the O_EXCL and O_CREAT flags of the POSIX open() |
1301 | ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the |
1302 | ** SQLITE_OPEN_CREATE, is used to indicate that file should always |
1303 | ** be created, and that it is an error if it already exists. |
1304 | ** It is <i>not</i> used to indicate the file should be opened |
1305 | ** for exclusive access. |
1306 | ** |
1307 | ** ^At least szOsFile bytes of memory are allocated by SQLite |
1308 | ** to hold the [sqlite3_file] structure passed as the third |
1309 | ** argument to xOpen. The xOpen method does not have to |
1310 | ** allocate the structure; it should just fill it in. Note that |
1311 | ** the xOpen method must set the sqlite3_file.pMethods to either |
1312 | ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do |
1313 | ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods |
1314 | ** element will be valid after xOpen returns regardless of the success |
1315 | ** or failure of the xOpen call. |
1316 | ** |
1317 | ** [[sqlite3_vfs.xAccess]] |
1318 | ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] |
1319 | ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to |
1320 | ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] |
1321 | ** to test whether a file is at least readable. The SQLITE_ACCESS_READ |
1322 | ** flag is never actually used and is not implemented in the built-in |
1323 | ** VFSes of SQLite. The file is named by the second argument and can be a |
1324 | ** directory. The xAccess method returns [SQLITE_OK] on success or some |
1325 | ** non-zero error code if there is an I/O error or if the name of |
1326 | ** the file given in the second argument is illegal. If SQLITE_OK |
1327 | ** is returned, then non-zero or zero is written into *pResOut to indicate |
1328 | ** whether or not the file is accessible. |
1329 | ** |
1330 | ** ^SQLite will always allocate at least mxPathname+1 bytes for the |
1331 | ** output buffer xFullPathname. The exact size of the output buffer |
1332 | ** is also passed as a parameter to both methods. If the output buffer |
1333 | ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is |
1334 | ** handled as a fatal error by SQLite, vfs implementations should endeavor |
1335 | ** to prevent this by setting mxPathname to a sufficiently large value. |
1336 | ** |
1337 | ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() |
1338 | ** interfaces are not strictly a part of the filesystem, but they are |
1339 | ** included in the VFS structure for completeness. |
1340 | ** The xRandomness() function attempts to return nBytes bytes |
1341 | ** of good-quality randomness into zOut. The return value is |
1342 | ** the actual number of bytes of randomness obtained. |
1343 | ** The xSleep() method causes the calling thread to sleep for at |
1344 | ** least the number of microseconds given. ^The xCurrentTime() |
1345 | ** method returns a Julian Day Number for the current date and time as |
1346 | ** a floating point value. |
1347 | ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian |
1348 | ** Day Number multiplied by 86400000 (the number of milliseconds in |
1349 | ** a 24-hour day). |
1350 | ** ^SQLite will use the xCurrentTimeInt64() method to get the current |
1351 | ** date and time if that method is available (if iVersion is 2 or |
1352 | ** greater and the function pointer is not NULL) and will fall back |
1353 | ** to xCurrentTime() if xCurrentTimeInt64() is unavailable. |
1354 | ** |
1355 | ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces |
1356 | ** are not used by the SQLite core. These optional interfaces are provided |
1357 | ** by some VFSes to facilitate testing of the VFS code. By overriding |
1358 | ** system calls with functions under its control, a test program can |
1359 | ** simulate faults and error conditions that would otherwise be difficult |
1360 | ** or impossible to induce. The set of system calls that can be overridden |
1361 | ** varies from one VFS to another, and from one version of the same VFS to the |
1362 | ** next. Applications that use these interfaces must be prepared for any |
1363 | ** or all of these interfaces to be NULL or for their behavior to change |
1364 | ** from one release to the next. Applications must not attempt to access |
1365 | ** any of these methods if the iVersion of the VFS is less than 3. |
1366 | */ |
1367 | typedef struct sqlite3_vfs sqlite3_vfs; |
1368 | typedef void (*sqlite3_syscall_ptr)(void); |
1369 | struct sqlite3_vfs { |
1370 | int iVersion; /* Structure version number (currently 3) */ |
1371 | int szOsFile; /* Size of subclassed sqlite3_file */ |
1372 | int mxPathname; /* Maximum file pathname length */ |
1373 | sqlite3_vfs *pNext; /* Next registered VFS */ |
1374 | const char *zName; /* Name of this virtual file system */ |
1375 | void *pAppData; /* Pointer to application-specific data */ |
1376 | int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*, |
1377 | int flags, int *pOutFlags); |
1378 | int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); |
1379 | int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); |
1380 | int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); |
1381 | void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); |
1382 | void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); |
1383 | void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); |
1384 | void (*xDlClose)(sqlite3_vfs*, void*); |
1385 | int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); |
1386 | int (*xSleep)(sqlite3_vfs*, int microseconds); |
1387 | int (*xCurrentTime)(sqlite3_vfs*, double*); |
1388 | int (*xGetLastError)(sqlite3_vfs*, int, char *); |
1389 | /* |
1390 | ** The methods above are in version 1 of the sqlite_vfs object |
1391 | ** definition. Those that follow are added in version 2 or later |
1392 | */ |
1393 | int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*); |
1394 | /* |
1395 | ** The methods above are in versions 1 and 2 of the sqlite_vfs object. |
1396 | ** Those below are for version 3 and greater. |
1397 | */ |
1398 | int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr); |
1399 | sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName); |
1400 | const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName); |
1401 | /* |
1402 | ** The methods above are in versions 1 through 3 of the sqlite_vfs object. |
1403 | ** New fields may be appended in future versions. The iVersion |
1404 | ** value will increment whenever this happens. |
1405 | */ |
1406 | }; |
1407 | |
1408 | /* |
1409 | ** CAPI3REF: Flags for the xAccess VFS method |
1410 | ** |
1411 | ** These integer constants can be used as the third parameter to |
1412 | ** the xAccess method of an [sqlite3_vfs] object. They determine |
1413 | ** what kind of permissions the xAccess method is looking for. |
1414 | ** With SQLITE_ACCESS_EXISTS, the xAccess method |
1415 | ** simply checks whether the file exists. |
1416 | ** With SQLITE_ACCESS_READWRITE, the xAccess method |
1417 | ** checks whether the named directory is both readable and writable |
1418 | ** (in other words, if files can be added, removed, and renamed within |
1419 | ** the directory). |
1420 | ** The SQLITE_ACCESS_READWRITE constant is currently used only by the |
1421 | ** [temp_store_directory pragma], though this could change in a future |
1422 | ** release of SQLite. |
1423 | ** With SQLITE_ACCESS_READ, the xAccess method |
1424 | ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is |
1425 | ** currently unused, though it might be used in a future release of |
1426 | ** SQLite. |
1427 | */ |
1428 | #define SQLITE_ACCESS_EXISTS 0 |
1429 | #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */ |
1430 | #define SQLITE_ACCESS_READ 2 /* Unused */ |
1431 | |
1432 | /* |
1433 | ** CAPI3REF: Flags for the xShmLock VFS method |
1434 | ** |
1435 | ** These integer constants define the various locking operations |
1436 | ** allowed by the xShmLock method of [sqlite3_io_methods]. The |
1437 | ** following are the only legal combinations of flags to the |
1438 | ** xShmLock method: |
1439 | ** |
1440 | ** <ul> |
1441 | ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED |
1442 | ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE |
1443 | ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED |
1444 | ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE |
1445 | ** </ul> |
1446 | ** |
1447 | ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as |
1448 | ** was given on the corresponding lock. |
1449 | ** |
1450 | ** The xShmLock method can transition between unlocked and SHARED or |
1451 | ** between unlocked and EXCLUSIVE. It cannot transition between SHARED |
1452 | ** and EXCLUSIVE. |
1453 | */ |
1454 | #define SQLITE_SHM_UNLOCK 1 |
1455 | #define SQLITE_SHM_LOCK 2 |
1456 | #define SQLITE_SHM_SHARED 4 |
1457 | #define SQLITE_SHM_EXCLUSIVE 8 |
1458 | |
1459 | /* |
1460 | ** CAPI3REF: Maximum xShmLock index |
1461 | ** |
1462 | ** The xShmLock method on [sqlite3_io_methods] may use values |
1463 | ** between 0 and this upper bound as its "offset" argument. |
1464 | ** The SQLite core will never attempt to acquire or release a |
1465 | ** lock outside of this range |
1466 | */ |
1467 | #define SQLITE_SHM_NLOCK 8 |
1468 | |
1469 | |
1470 | /* |
1471 | ** CAPI3REF: Initialize The SQLite Library |
1472 | ** |
1473 | ** ^The sqlite3_initialize() routine initializes the |
1474 | ** SQLite library. ^The sqlite3_shutdown() routine |
1475 | ** deallocates any resources that were allocated by sqlite3_initialize(). |
1476 | ** These routines are designed to aid in process initialization and |
1477 | ** shutdown on embedded systems. Workstation applications using |
1478 | ** SQLite normally do not need to invoke either of these routines. |
1479 | ** |
1480 | ** A call to sqlite3_initialize() is an "effective" call if it is |
1481 | ** the first time sqlite3_initialize() is invoked during the lifetime of |
1482 | ** the process, or if it is the first time sqlite3_initialize() is invoked |
1483 | ** following a call to sqlite3_shutdown(). ^(Only an effective call |
1484 | ** of sqlite3_initialize() does any initialization. All other calls |
1485 | ** are harmless no-ops.)^ |
1486 | ** |
1487 | ** A call to sqlite3_shutdown() is an "effective" call if it is the first |
1488 | ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only |
1489 | ** an effective call to sqlite3_shutdown() does any deinitialization. |
1490 | ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^ |
1491 | ** |
1492 | ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown() |
1493 | ** is not. The sqlite3_shutdown() interface must only be called from a |
1494 | ** single thread. All open [database connections] must be closed and all |
1495 | ** other SQLite resources must be deallocated prior to invoking |
1496 | ** sqlite3_shutdown(). |
1497 | ** |
1498 | ** Among other things, ^sqlite3_initialize() will invoke |
1499 | ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown() |
1500 | ** will invoke sqlite3_os_end(). |
1501 | ** |
1502 | ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success. |
1503 | ** ^If for some reason, sqlite3_initialize() is unable to initialize |
1504 | ** the library (perhaps it is unable to allocate a needed resource such |
1505 | ** as a mutex) it returns an [error code] other than [SQLITE_OK]. |
1506 | ** |
1507 | ** ^The sqlite3_initialize() routine is called internally by many other |
1508 | ** SQLite interfaces so that an application usually does not need to |
1509 | ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] |
1510 | ** calls sqlite3_initialize() so the SQLite library will be automatically |
1511 | ** initialized when [sqlite3_open()] is called if it has not be initialized |
1512 | ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] |
1513 | ** compile-time option, then the automatic calls to sqlite3_initialize() |
1514 | ** are omitted and the application must call sqlite3_initialize() directly |
1515 | ** prior to using any other SQLite interface. For maximum portability, |
1516 | ** it is recommended that applications always invoke sqlite3_initialize() |
1517 | ** directly prior to using any other SQLite interface. Future releases |
1518 | ** of SQLite may require this. In other words, the behavior exhibited |
1519 | ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the |
1520 | ** default behavior in some future release of SQLite. |
1521 | ** |
1522 | ** The sqlite3_os_init() routine does operating-system specific |
1523 | ** initialization of the SQLite library. The sqlite3_os_end() |
1524 | ** routine undoes the effect of sqlite3_os_init(). Typical tasks |
1525 | ** performed by these routines include allocation or deallocation |
1526 | ** of static resources, initialization of global variables, |
1527 | ** setting up a default [sqlite3_vfs] module, or setting up |
1528 | ** a default configuration using [sqlite3_config()]. |
1529 | ** |
1530 | ** The application should never invoke either sqlite3_os_init() |
1531 | ** or sqlite3_os_end() directly. The application should only invoke |
1532 | ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() |
1533 | ** interface is called automatically by sqlite3_initialize() and |
1534 | ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate |
1535 | ** implementations for sqlite3_os_init() and sqlite3_os_end() |
1536 | ** are built into SQLite when it is compiled for Unix, Windows, or OS/2. |
1537 | ** When [custom builds | built for other platforms] |
1538 | ** (using the [SQLITE_OS_OTHER=1] compile-time |
1539 | ** option) the application must supply a suitable implementation for |
1540 | ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied |
1541 | ** implementation of sqlite3_os_init() or sqlite3_os_end() |
1542 | ** must return [SQLITE_OK] on success and some other [error code] upon |
1543 | ** failure. |
1544 | */ |
1545 | SQLITE_API int sqlite3_initialize(void); |
1546 | SQLITE_API int sqlite3_shutdown(void); |
1547 | SQLITE_API int sqlite3_os_init(void); |
1548 | SQLITE_API int sqlite3_os_end(void); |
1549 | |
1550 | /* |
1551 | ** CAPI3REF: Configuring The SQLite Library |
1552 | ** |
1553 | ** The sqlite3_config() interface is used to make global configuration |
1554 | ** changes to SQLite in order to tune SQLite to the specific needs of |
1555 | ** the application. The default configuration is recommended for most |
1556 | ** applications and so this routine is usually not necessary. It is |
1557 | ** provided to support rare applications with unusual needs. |
1558 | ** |
1559 | ** <b>The sqlite3_config() interface is not threadsafe. The application |
1560 | ** must ensure that no other SQLite interfaces are invoked by other |
1561 | ** threads while sqlite3_config() is running.</b> |
1562 | ** |
1563 | ** The sqlite3_config() interface |
1564 | ** may only be invoked prior to library initialization using |
1565 | ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. |
1566 | ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before |
1567 | ** [sqlite3_shutdown()] then it will return SQLITE_MISUSE. |
1568 | ** Note, however, that ^sqlite3_config() can be called as part of the |
1569 | ** implementation of an application-defined [sqlite3_os_init()]. |
1570 | ** |
1571 | ** The first argument to sqlite3_config() is an integer |
1572 | ** [configuration option] that determines |
1573 | ** what property of SQLite is to be configured. Subsequent arguments |
1574 | ** vary depending on the [configuration option] |
1575 | ** in the first argument. |
1576 | ** |
1577 | ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. |
1578 | ** ^If the option is unknown or SQLite is unable to set the option |
1579 | ** then this routine returns a non-zero [error code]. |
1580 | */ |
1581 | SQLITE_API int sqlite3_config(int, ...); |
1582 | |
1583 | /* |
1584 | ** CAPI3REF: Configure database connections |
1585 | ** METHOD: sqlite3 |
1586 | ** |
1587 | ** The sqlite3_db_config() interface is used to make configuration |
1588 | ** changes to a [database connection]. The interface is similar to |
1589 | ** [sqlite3_config()] except that the changes apply to a single |
1590 | ** [database connection] (specified in the first argument). |
1591 | ** |
1592 | ** The second argument to sqlite3_db_config(D,V,...) is the |
1593 | ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code |
1594 | ** that indicates what aspect of the [database connection] is being configured. |
1595 | ** Subsequent arguments vary depending on the configuration verb. |
1596 | ** |
1597 | ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if |
1598 | ** the call is considered successful. |
1599 | */ |
1600 | SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...); |
1601 | |
1602 | /* |
1603 | ** CAPI3REF: Memory Allocation Routines |
1604 | ** |
1605 | ** An instance of this object defines the interface between SQLite |
1606 | ** and low-level memory allocation routines. |
1607 | ** |
1608 | ** This object is used in only one place in the SQLite interface. |
1609 | ** A pointer to an instance of this object is the argument to |
1610 | ** [sqlite3_config()] when the configuration option is |
1611 | ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. |
1612 | ** By creating an instance of this object |
1613 | ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) |
1614 | ** during configuration, an application can specify an alternative |
1615 | ** memory allocation subsystem for SQLite to use for all of its |
1616 | ** dynamic memory needs. |
1617 | ** |
1618 | ** Note that SQLite comes with several [built-in memory allocators] |
1619 | ** that are perfectly adequate for the overwhelming majority of applications |
1620 | ** and that this object is only useful to a tiny minority of applications |
1621 | ** with specialized memory allocation requirements. This object is |
1622 | ** also used during testing of SQLite in order to specify an alternative |
1623 | ** memory allocator that simulates memory out-of-memory conditions in |
1624 | ** order to verify that SQLite recovers gracefully from such |
1625 | ** conditions. |
1626 | ** |
1627 | ** The xMalloc, xRealloc, and xFree methods must work like the |
1628 | ** malloc(), realloc() and free() functions from the standard C library. |
1629 | ** ^SQLite guarantees that the second argument to |
1630 | ** xRealloc is always a value returned by a prior call to xRoundup. |
1631 | ** |
1632 | ** xSize should return the allocated size of a memory allocation |
1633 | ** previously obtained from xMalloc or xRealloc. The allocated size |
1634 | ** is always at least as big as the requested size but may be larger. |
1635 | ** |
1636 | ** The xRoundup method returns what would be the allocated size of |
1637 | ** a memory allocation given a particular requested size. Most memory |
1638 | ** allocators round up memory allocations at least to the next multiple |
1639 | ** of 8. Some allocators round up to a larger multiple or to a power of 2. |
1640 | ** Every memory allocation request coming in through [sqlite3_malloc()] |
1641 | ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, |
1642 | ** that causes the corresponding memory allocation to fail. |
1643 | ** |
1644 | ** The xInit method initializes the memory allocator. For example, |
1645 | ** it might allocate any required mutexes or initialize internal data |
1646 | ** structures. The xShutdown method is invoked (indirectly) by |
1647 | ** [sqlite3_shutdown()] and should deallocate any resources acquired |
1648 | ** by xInit. The pAppData pointer is used as the only parameter to |
1649 | ** xInit and xShutdown. |
1650 | ** |
1651 | ** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes |
1652 | ** the xInit method, so the xInit method need not be threadsafe. The |
1653 | ** xShutdown method is only called from [sqlite3_shutdown()] so it does |
1654 | ** not need to be threadsafe either. For all other methods, SQLite |
1655 | ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the |
1656 | ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which |
1657 | ** it is by default) and so the methods are automatically serialized. |
1658 | ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other |
1659 | ** methods must be threadsafe or else make their own arrangements for |
1660 | ** serialization. |
1661 | ** |
1662 | ** SQLite will never invoke xInit() more than once without an intervening |
1663 | ** call to xShutdown(). |
1664 | */ |
1665 | typedef struct sqlite3_mem_methods sqlite3_mem_methods; |
1666 | struct sqlite3_mem_methods { |
1667 | void *(*xMalloc)(int); /* Memory allocation function */ |
1668 | void (*xFree)(void*); /* Free a prior allocation */ |
1669 | void *(*xRealloc)(void*,int); /* Resize an allocation */ |
1670 | int (*xSize)(void*); /* Return the size of an allocation */ |
1671 | int (*xRoundup)(int); /* Round up request size to allocation size */ |
1672 | int (*xInit)(void*); /* Initialize the memory allocator */ |
1673 | void (*xShutdown)(void*); /* Deinitialize the memory allocator */ |
1674 | void *pAppData; /* Argument to xInit() and xShutdown() */ |
1675 | }; |
1676 | |
1677 | /* |
1678 | ** CAPI3REF: Configuration Options |
1679 | ** KEYWORDS: {configuration option} |
1680 | ** |
1681 | ** These constants are the available integer configuration options that |
1682 | ** can be passed as the first argument to the [sqlite3_config()] interface. |
1683 | ** |
1684 | ** New configuration options may be added in future releases of SQLite. |
1685 | ** Existing configuration options might be discontinued. Applications |
1686 | ** should check the return code from [sqlite3_config()] to make sure that |
1687 | ** the call worked. The [sqlite3_config()] interface will return a |
1688 | ** non-zero [error code] if a discontinued or unsupported configuration option |
1689 | ** is invoked. |
1690 | ** |
1691 | ** <dl> |
1692 | ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt> |
1693 | ** <dd>There are no arguments to this option. ^This option sets the |
1694 | ** [threading mode] to Single-thread. In other words, it disables |
1695 | ** all mutexing and puts SQLite into a mode where it can only be used |
1696 | ** by a single thread. ^If SQLite is compiled with |
1697 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
1698 | ** it is not possible to change the [threading mode] from its default |
1699 | ** value of Single-thread and so [sqlite3_config()] will return |
1700 | ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD |
1701 | ** configuration option.</dd> |
1702 | ** |
1703 | ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt> |
1704 | ** <dd>There are no arguments to this option. ^This option sets the |
1705 | ** [threading mode] to Multi-thread. In other words, it disables |
1706 | ** mutexing on [database connection] and [prepared statement] objects. |
1707 | ** The application is responsible for serializing access to |
1708 | ** [database connections] and [prepared statements]. But other mutexes |
1709 | ** are enabled so that SQLite will be safe to use in a multi-threaded |
1710 | ** environment as long as no two threads attempt to use the same |
1711 | ** [database connection] at the same time. ^If SQLite is compiled with |
1712 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
1713 | ** it is not possible to set the Multi-thread [threading mode] and |
1714 | ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the |
1715 | ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd> |
1716 | ** |
1717 | ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt> |
1718 | ** <dd>There are no arguments to this option. ^This option sets the |
1719 | ** [threading mode] to Serialized. In other words, this option enables |
1720 | ** all mutexes including the recursive |
1721 | ** mutexes on [database connection] and [prepared statement] objects. |
1722 | ** In this mode (which is the default when SQLite is compiled with |
1723 | ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access |
1724 | ** to [database connections] and [prepared statements] so that the |
1725 | ** application is free to use the same [database connection] or the |
1726 | ** same [prepared statement] in different threads at the same time. |
1727 | ** ^If SQLite is compiled with |
1728 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
1729 | ** it is not possible to set the Serialized [threading mode] and |
1730 | ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the |
1731 | ** SQLITE_CONFIG_SERIALIZED configuration option.</dd> |
1732 | ** |
1733 | ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt> |
1734 | ** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is |
1735 | ** a pointer to an instance of the [sqlite3_mem_methods] structure. |
1736 | ** The argument specifies |
1737 | ** alternative low-level memory allocation routines to be used in place of |
1738 | ** the memory allocation routines built into SQLite.)^ ^SQLite makes |
1739 | ** its own private copy of the content of the [sqlite3_mem_methods] structure |
1740 | ** before the [sqlite3_config()] call returns.</dd> |
1741 | ** |
1742 | ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt> |
1743 | ** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which |
1744 | ** is a pointer to an instance of the [sqlite3_mem_methods] structure. |
1745 | ** The [sqlite3_mem_methods] |
1746 | ** structure is filled with the currently defined memory allocation routines.)^ |
1747 | ** This option can be used to overload the default memory allocation |
1748 | ** routines with a wrapper that simulations memory allocation failure or |
1749 | ** tracks memory usage, for example. </dd> |
1750 | ** |
1751 | ** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt> |
1752 | ** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of |
1753 | ** type int, interpreted as a boolean, which if true provides a hint to |
1754 | ** SQLite that it should avoid large memory allocations if possible. |
1755 | ** SQLite will run faster if it is free to make large memory allocations, |
1756 | ** but some application might prefer to run slower in exchange for |
1757 | ** guarantees about memory fragmentation that are possible if large |
1758 | ** allocations are avoided. This hint is normally off. |
1759 | ** </dd> |
1760 | ** |
1761 | ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt> |
1762 | ** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int, |
1763 | ** interpreted as a boolean, which enables or disables the collection of |
1764 | ** memory allocation statistics. ^(When memory allocation statistics are |
1765 | ** disabled, the following SQLite interfaces become non-operational: |
1766 | ** <ul> |
1767 | ** <li> [sqlite3_hard_heap_limit64()] |
1768 | ** <li> [sqlite3_memory_used()] |
1769 | ** <li> [sqlite3_memory_highwater()] |
1770 | ** <li> [sqlite3_soft_heap_limit64()] |
1771 | ** <li> [sqlite3_status64()] |
1772 | ** </ul>)^ |
1773 | ** ^Memory allocation statistics are enabled by default unless SQLite is |
1774 | ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory |
1775 | ** allocation statistics are disabled by default. |
1776 | ** </dd> |
1777 | ** |
1778 | ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt> |
1779 | ** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used. |
1780 | ** </dd> |
1781 | ** |
1782 | ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt> |
1783 | ** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool |
1784 | ** that SQLite can use for the database page cache with the default page |
1785 | ** cache implementation. |
1786 | ** This configuration option is a no-op if an application-defined page |
1787 | ** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2]. |
1788 | ** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to |
1789 | ** 8-byte aligned memory (pMem), the size of each page cache line (sz), |
1790 | ** and the number of cache lines (N). |
1791 | ** The sz argument should be the size of the largest database page |
1792 | ** (a power of two between 512 and 65536) plus some extra bytes for each |
1793 | ** page header. ^The number of extra bytes needed by the page header |
1794 | ** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ]. |
1795 | ** ^It is harmless, apart from the wasted memory, |
1796 | ** for the sz parameter to be larger than necessary. The pMem |
1797 | ** argument must be either a NULL pointer or a pointer to an 8-byte |
1798 | ** aligned block of memory of at least sz*N bytes, otherwise |
1799 | ** subsequent behavior is undefined. |
1800 | ** ^When pMem is not NULL, SQLite will strive to use the memory provided |
1801 | ** to satisfy page cache needs, falling back to [sqlite3_malloc()] if |
1802 | ** a page cache line is larger than sz bytes or if all of the pMem buffer |
1803 | ** is exhausted. |
1804 | ** ^If pMem is NULL and N is non-zero, then each database connection |
1805 | ** does an initial bulk allocation for page cache memory |
1806 | ** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or |
1807 | ** of -1024*N bytes if N is negative, . ^If additional |
1808 | ** page cache memory is needed beyond what is provided by the initial |
1809 | ** allocation, then SQLite goes to [sqlite3_malloc()] separately for each |
1810 | ** additional cache line. </dd> |
1811 | ** |
1812 | ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt> |
1813 | ** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer |
1814 | ** that SQLite will use for all of its dynamic memory allocation needs |
1815 | ** beyond those provided for by [SQLITE_CONFIG_PAGECACHE]. |
1816 | ** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled |
1817 | ** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns |
1818 | ** [SQLITE_ERROR] if invoked otherwise. |
1819 | ** ^There are three arguments to SQLITE_CONFIG_HEAP: |
1820 | ** An 8-byte aligned pointer to the memory, |
1821 | ** the number of bytes in the memory buffer, and the minimum allocation size. |
1822 | ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts |
1823 | ** to using its default memory allocator (the system malloc() implementation), |
1824 | ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the |
1825 | ** memory pointer is not NULL then the alternative memory |
1826 | ** allocator is engaged to handle all of SQLites memory allocation needs. |
1827 | ** The first pointer (the memory pointer) must be aligned to an 8-byte |
1828 | ** boundary or subsequent behavior of SQLite will be undefined. |
1829 | ** The minimum allocation size is capped at 2**12. Reasonable values |
1830 | ** for the minimum allocation size are 2**5 through 2**8.</dd> |
1831 | ** |
1832 | ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt> |
1833 | ** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a |
1834 | ** pointer to an instance of the [sqlite3_mutex_methods] structure. |
1835 | ** The argument specifies alternative low-level mutex routines to be used |
1836 | ** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of |
1837 | ** the content of the [sqlite3_mutex_methods] structure before the call to |
1838 | ** [sqlite3_config()] returns. ^If SQLite is compiled with |
1839 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
1840 | ** the entire mutexing subsystem is omitted from the build and hence calls to |
1841 | ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will |
1842 | ** return [SQLITE_ERROR].</dd> |
1843 | ** |
1844 | ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt> |
1845 | ** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which |
1846 | ** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The |
1847 | ** [sqlite3_mutex_methods] |
1848 | ** structure is filled with the currently defined mutex routines.)^ |
1849 | ** This option can be used to overload the default mutex allocation |
1850 | ** routines with a wrapper used to track mutex usage for performance |
1851 | ** profiling or testing, for example. ^If SQLite is compiled with |
1852 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
1853 | ** the entire mutexing subsystem is omitted from the build and hence calls to |
1854 | ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will |
1855 | ** return [SQLITE_ERROR].</dd> |
1856 | ** |
1857 | ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt> |
1858 | ** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine |
1859 | ** the default size of lookaside memory on each [database connection]. |
1860 | ** The first argument is the |
1861 | ** size of each lookaside buffer slot and the second is the number of |
1862 | ** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE |
1863 | ** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] |
1864 | ** option to [sqlite3_db_config()] can be used to change the lookaside |
1865 | ** configuration on individual connections.)^ </dd> |
1866 | ** |
1867 | ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt> |
1868 | ** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is |
1869 | ** a pointer to an [sqlite3_pcache_methods2] object. This object specifies |
1870 | ** the interface to a custom page cache implementation.)^ |
1871 | ** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd> |
1872 | ** |
1873 | ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt> |
1874 | ** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which |
1875 | ** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of |
1876 | ** the current page cache implementation into that object.)^ </dd> |
1877 | ** |
1878 | ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt> |
1879 | ** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite |
1880 | ** global [error log]. |
1881 | ** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a |
1882 | ** function with a call signature of void(*)(void*,int,const char*), |
1883 | ** and a pointer to void. ^If the function pointer is not NULL, it is |
1884 | ** invoked by [sqlite3_log()] to process each logging event. ^If the |
1885 | ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op. |
1886 | ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is |
1887 | ** passed through as the first parameter to the application-defined logger |
1888 | ** function whenever that function is invoked. ^The second parameter to |
1889 | ** the logger function is a copy of the first parameter to the corresponding |
1890 | ** [sqlite3_log()] call and is intended to be a [result code] or an |
1891 | ** [extended result code]. ^The third parameter passed to the logger is |
1892 | ** log message after formatting via [sqlite3_snprintf()]. |
1893 | ** The SQLite logging interface is not reentrant; the logger function |
1894 | ** supplied by the application must not invoke any SQLite interface. |
1895 | ** In a multi-threaded application, the application-defined logger |
1896 | ** function must be threadsafe. </dd> |
1897 | ** |
1898 | ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI |
1899 | ** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int. |
1900 | ** If non-zero, then URI handling is globally enabled. If the parameter is zero, |
1901 | ** then URI handling is globally disabled.)^ ^If URI handling is globally |
1902 | ** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()], |
1903 | ** [sqlite3_open16()] or |
1904 | ** specified as part of [ATTACH] commands are interpreted as URIs, regardless |
1905 | ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database |
1906 | ** connection is opened. ^If it is globally disabled, filenames are |
1907 | ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the |
1908 | ** database connection is opened. ^(By default, URI handling is globally |
1909 | ** disabled. The default value may be changed by compiling with the |
1910 | ** [SQLITE_USE_URI] symbol defined.)^ |
1911 | ** |
1912 | ** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN |
1913 | ** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer |
1914 | ** argument which is interpreted as a boolean in order to enable or disable |
1915 | ** the use of covering indices for full table scans in the query optimizer. |
1916 | ** ^The default setting is determined |
1917 | ** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on" |
1918 | ** if that compile-time option is omitted. |
1919 | ** The ability to disable the use of covering indices for full table scans |
1920 | ** is because some incorrectly coded legacy applications might malfunction |
1921 | ** when the optimization is enabled. Providing the ability to |
1922 | ** disable the optimization allows the older, buggy application code to work |
1923 | ** without change even with newer versions of SQLite. |
1924 | ** |
1925 | ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]] |
1926 | ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE |
1927 | ** <dd> These options are obsolete and should not be used by new code. |
1928 | ** They are retained for backwards compatibility but are now no-ops. |
1929 | ** </dd> |
1930 | ** |
1931 | ** [[SQLITE_CONFIG_SQLLOG]] |
1932 | ** <dt>SQLITE_CONFIG_SQLLOG |
1933 | ** <dd>This option is only available if sqlite is compiled with the |
1934 | ** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should |
1935 | ** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int). |
1936 | ** The second should be of type (void*). The callback is invoked by the library |
1937 | ** in three separate circumstances, identified by the value passed as the |
1938 | ** fourth parameter. If the fourth parameter is 0, then the database connection |
1939 | ** passed as the second argument has just been opened. The third argument |
1940 | ** points to a buffer containing the name of the main database file. If the |
1941 | ** fourth parameter is 1, then the SQL statement that the third parameter |
1942 | ** points to has just been executed. Or, if the fourth parameter is 2, then |
1943 | ** the connection being passed as the second parameter is being closed. The |
1944 | ** third parameter is passed NULL In this case. An example of using this |
1945 | ** configuration option can be seen in the "test_sqllog.c" source file in |
1946 | ** the canonical SQLite source tree.</dd> |
1947 | ** |
1948 | ** [[SQLITE_CONFIG_MMAP_SIZE]] |
1949 | ** <dt>SQLITE_CONFIG_MMAP_SIZE |
1950 | ** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values |
1951 | ** that are the default mmap size limit (the default setting for |
1952 | ** [PRAGMA mmap_size]) and the maximum allowed mmap size limit. |
1953 | ** ^The default setting can be overridden by each database connection using |
1954 | ** either the [PRAGMA mmap_size] command, or by using the |
1955 | ** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size |
1956 | ** will be silently truncated if necessary so that it does not exceed the |
1957 | ** compile-time maximum mmap size set by the |
1958 | ** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^ |
1959 | ** ^If either argument to this option is negative, then that argument is |
1960 | ** changed to its compile-time default. |
1961 | ** |
1962 | ** [[SQLITE_CONFIG_WIN32_HEAPSIZE]] |
1963 | ** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE |
1964 | ** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is |
1965 | ** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro |
1966 | ** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value |
1967 | ** that specifies the maximum size of the created heap. |
1968 | ** |
1969 | ** [[SQLITE_CONFIG_PCACHE_HDRSZ]] |
1970 | ** <dt>SQLITE_CONFIG_PCACHE_HDRSZ |
1971 | ** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which |
1972 | ** is a pointer to an integer and writes into that integer the number of extra |
1973 | ** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE]. |
1974 | ** The amount of extra space required can change depending on the compiler, |
1975 | ** target platform, and SQLite version. |
1976 | ** |
1977 | ** [[SQLITE_CONFIG_PMASZ]] |
1978 | ** <dt>SQLITE_CONFIG_PMASZ |
1979 | ** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which |
1980 | ** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded |
1981 | ** sorter to that integer. The default minimum PMA Size is set by the |
1982 | ** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched |
1983 | ** to help with sort operations when multithreaded sorting |
1984 | ** is enabled (using the [PRAGMA threads] command) and the amount of content |
1985 | ** to be sorted exceeds the page size times the minimum of the |
1986 | ** [PRAGMA cache_size] setting and this value. |
1987 | ** |
1988 | ** [[SQLITE_CONFIG_STMTJRNL_SPILL]] |
1989 | ** <dt>SQLITE_CONFIG_STMTJRNL_SPILL |
1990 | ** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which |
1991 | ** becomes the [statement journal] spill-to-disk threshold. |
1992 | ** [Statement journals] are held in memory until their size (in bytes) |
1993 | ** exceeds this threshold, at which point they are written to disk. |
1994 | ** Or if the threshold is -1, statement journals are always held |
1995 | ** exclusively in memory. |
1996 | ** Since many statement journals never become large, setting the spill |
1997 | ** threshold to a value such as 64KiB can greatly reduce the amount of |
1998 | ** I/O required to support statement rollback. |
1999 | ** The default value for this setting is controlled by the |
2000 | ** [SQLITE_STMTJRNL_SPILL] compile-time option. |
2001 | ** |
2002 | ** [[SQLITE_CONFIG_SORTERREF_SIZE]] |
2003 | ** <dt>SQLITE_CONFIG_SORTERREF_SIZE |
2004 | ** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter |
2005 | ** of type (int) - the new value of the sorter-reference size threshold. |
2006 | ** Usually, when SQLite uses an external sort to order records according |
2007 | ** to an ORDER BY clause, all fields required by the caller are present in the |
2008 | ** sorted records. However, if SQLite determines based on the declared type |
2009 | ** of a table column that its values are likely to be very large - larger |
2010 | ** than the configured sorter-reference size threshold - then a reference |
2011 | ** is stored in each sorted record and the required column values loaded |
2012 | ** from the database as records are returned in sorted order. The default |
2013 | ** value for this option is to never use this optimization. Specifying a |
2014 | ** negative value for this option restores the default behaviour. |
2015 | ** This option is only available if SQLite is compiled with the |
2016 | ** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option. |
2017 | ** |
2018 | ** [[SQLITE_CONFIG_MEMDB_MAXSIZE]] |
2019 | ** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE |
2020 | ** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter |
2021 | ** [sqlite3_int64] parameter which is the default maximum size for an in-memory |
2022 | ** database created using [sqlite3_deserialize()]. This default maximum |
2023 | ** size can be adjusted up or down for individual databases using the |
2024 | ** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control]. If this |
2025 | ** configuration setting is never used, then the default maximum is determined |
2026 | ** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option. If that |
2027 | ** compile-time option is not set, then the default maximum is 1073741824. |
2028 | ** </dl> |
2029 | */ |
2030 | #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ |
2031 | #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ |
2032 | #define SQLITE_CONFIG_SERIALIZED 3 /* nil */ |
2033 | #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ |
2034 | #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ |
2035 | #define SQLITE_CONFIG_SCRATCH 6 /* No longer used */ |
2036 | #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ |
2037 | #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ |
2038 | #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ |
2039 | #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ |
2040 | #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ |
2041 | /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ |
2042 | #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ |
2043 | #define SQLITE_CONFIG_PCACHE 14 /* no-op */ |
2044 | #define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ |
2045 | #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ |
2046 | #define SQLITE_CONFIG_URI 17 /* int */ |
2047 | #define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ |
2048 | #define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ |
2049 | #define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */ |
2050 | #define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */ |
2051 | #define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */ |
2052 | #define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */ |
2053 | #define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */ |
2054 | #define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */ |
2055 | #define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */ |
2056 | #define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */ |
2057 | #define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */ |
2058 | #define SQLITE_CONFIG_MEMDB_MAXSIZE 29 /* sqlite3_int64 */ |
2059 | |
2060 | /* |
2061 | ** CAPI3REF: Database Connection Configuration Options |
2062 | ** |
2063 | ** These constants are the available integer configuration options that |
2064 | ** can be passed as the second argument to the [sqlite3_db_config()] interface. |
2065 | ** |
2066 | ** New configuration options may be added in future releases of SQLite. |
2067 | ** Existing configuration options might be discontinued. Applications |
2068 | ** should check the return code from [sqlite3_db_config()] to make sure that |
2069 | ** the call worked. ^The [sqlite3_db_config()] interface will return a |
2070 | ** non-zero [error code] if a discontinued or unsupported configuration option |
2071 | ** is invoked. |
2072 | ** |
2073 | ** <dl> |
2074 | ** [[SQLITE_DBCONFIG_LOOKASIDE]] |
2075 | ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt> |
2076 | ** <dd> ^This option takes three additional arguments that determine the |
2077 | ** [lookaside memory allocator] configuration for the [database connection]. |
2078 | ** ^The first argument (the third parameter to [sqlite3_db_config()] is a |
2079 | ** pointer to a memory buffer to use for lookaside memory. |
2080 | ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb |
2081 | ** may be NULL in which case SQLite will allocate the |
2082 | ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the |
2083 | ** size of each lookaside buffer slot. ^The third argument is the number of |
2084 | ** slots. The size of the buffer in the first argument must be greater than |
2085 | ** or equal to the product of the second and third arguments. The buffer |
2086 | ** must be aligned to an 8-byte boundary. ^If the second argument to |
2087 | ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally |
2088 | ** rounded down to the next smaller multiple of 8. ^(The lookaside memory |
2089 | ** configuration for a database connection can only be changed when that |
2090 | ** connection is not currently using lookaside memory, or in other words |
2091 | ** when the "current value" returned by |
2092 | ** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero. |
2093 | ** Any attempt to change the lookaside memory configuration when lookaside |
2094 | ** memory is in use leaves the configuration unchanged and returns |
2095 | ** [SQLITE_BUSY].)^</dd> |
2096 | ** |
2097 | ** [[SQLITE_DBCONFIG_ENABLE_FKEY]] |
2098 | ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt> |
2099 | ** <dd> ^This option is used to enable or disable the enforcement of |
2100 | ** [foreign key constraints]. There should be two additional arguments. |
2101 | ** The first argument is an integer which is 0 to disable FK enforcement, |
2102 | ** positive to enable FK enforcement or negative to leave FK enforcement |
2103 | ** unchanged. The second parameter is a pointer to an integer into which |
2104 | ** is written 0 or 1 to indicate whether FK enforcement is off or on |
2105 | ** following this call. The second parameter may be a NULL pointer, in |
2106 | ** which case the FK enforcement setting is not reported back. </dd> |
2107 | ** |
2108 | ** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]] |
2109 | ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt> |
2110 | ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers]. |
2111 | ** There should be two additional arguments. |
2112 | ** The first argument is an integer which is 0 to disable triggers, |
2113 | ** positive to enable triggers or negative to leave the setting unchanged. |
2114 | ** The second parameter is a pointer to an integer into which |
2115 | ** is written 0 or 1 to indicate whether triggers are disabled or enabled |
2116 | ** following this call. The second parameter may be a NULL pointer, in |
2117 | ** which case the trigger setting is not reported back. </dd> |
2118 | ** |
2119 | ** [[SQLITE_DBCONFIG_ENABLE_VIEW]] |
2120 | ** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt> |
2121 | ** <dd> ^This option is used to enable or disable [CREATE VIEW | views]. |
2122 | ** There should be two additional arguments. |
2123 | ** The first argument is an integer which is 0 to disable views, |
2124 | ** positive to enable views or negative to leave the setting unchanged. |
2125 | ** The second parameter is a pointer to an integer into which |
2126 | ** is written 0 or 1 to indicate whether views are disabled or enabled |
2127 | ** following this call. The second parameter may be a NULL pointer, in |
2128 | ** which case the view setting is not reported back. </dd> |
2129 | ** |
2130 | ** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]] |
2131 | ** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt> |
2132 | ** <dd> ^This option is used to enable or disable the |
2133 | ** [fts3_tokenizer()] function which is part of the |
2134 | ** [FTS3] full-text search engine extension. |
2135 | ** There should be two additional arguments. |
2136 | ** The first argument is an integer which is 0 to disable fts3_tokenizer() or |
2137 | ** positive to enable fts3_tokenizer() or negative to leave the setting |
2138 | ** unchanged. |
2139 | ** The second parameter is a pointer to an integer into which |
2140 | ** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled |
2141 | ** following this call. The second parameter may be a NULL pointer, in |
2142 | ** which case the new setting is not reported back. </dd> |
2143 | ** |
2144 | ** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]] |
2145 | ** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt> |
2146 | ** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()] |
2147 | ** interface independently of the [load_extension()] SQL function. |
2148 | ** The [sqlite3_enable_load_extension()] API enables or disables both the |
2149 | ** C-API [sqlite3_load_extension()] and the SQL function [load_extension()]. |
2150 | ** There should be two additional arguments. |
2151 | ** When the first argument to this interface is 1, then only the C-API is |
2152 | ** enabled and the SQL function remains disabled. If the first argument to |
2153 | ** this interface is 0, then both the C-API and the SQL function are disabled. |
2154 | ** If the first argument is -1, then no changes are made to state of either the |
2155 | ** C-API or the SQL function. |
2156 | ** The second parameter is a pointer to an integer into which |
2157 | ** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface |
2158 | ** is disabled or enabled following this call. The second parameter may |
2159 | ** be a NULL pointer, in which case the new setting is not reported back. |
2160 | ** </dd> |
2161 | ** |
2162 | ** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt> |
2163 | ** <dd> ^This option is used to change the name of the "main" database |
2164 | ** schema. ^The sole argument is a pointer to a constant UTF8 string |
2165 | ** which will become the new schema name in place of "main". ^SQLite |
2166 | ** does not make a copy of the new main schema name string, so the application |
2167 | ** must ensure that the argument passed into this DBCONFIG option is unchanged |
2168 | ** until after the database connection closes. |
2169 | ** </dd> |
2170 | ** |
2171 | ** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]] |
2172 | ** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt> |
2173 | ** <dd> Usually, when a database in wal mode is closed or detached from a |
2174 | ** database handle, SQLite checks if this will mean that there are now no |
2175 | ** connections at all to the database. If so, it performs a checkpoint |
2176 | ** operation before closing the connection. This option may be used to |
2177 | ** override this behaviour. The first parameter passed to this operation |
2178 | ** is an integer - positive to disable checkpoints-on-close, or zero (the |
2179 | ** default) to enable them, and negative to leave the setting unchanged. |
2180 | ** The second parameter is a pointer to an integer |
2181 | ** into which is written 0 or 1 to indicate whether checkpoints-on-close |
2182 | ** have been disabled - 0 if they are not disabled, 1 if they are. |
2183 | ** </dd> |
2184 | ** |
2185 | ** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt> |
2186 | ** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates |
2187 | ** the [query planner stability guarantee] (QPSG). When the QPSG is active, |
2188 | ** a single SQL query statement will always use the same algorithm regardless |
2189 | ** of values of [bound parameters].)^ The QPSG disables some query optimizations |
2190 | ** that look at the values of bound parameters, which can make some queries |
2191 | ** slower. But the QPSG has the advantage of more predictable behavior. With |
2192 | ** the QPSG active, SQLite will always use the same query plan in the field as |
2193 | ** was used during testing in the lab. |
2194 | ** The first argument to this setting is an integer which is 0 to disable |
2195 | ** the QPSG, positive to enable QPSG, or negative to leave the setting |
2196 | ** unchanged. The second parameter is a pointer to an integer into which |
2197 | ** is written 0 or 1 to indicate whether the QPSG is disabled or enabled |
2198 | ** following this call. |
2199 | ** </dd> |
2200 | ** |
2201 | ** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt> |
2202 | ** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not |
2203 | ** include output for any operations performed by trigger programs. This |
2204 | ** option is used to set or clear (the default) a flag that governs this |
2205 | ** behavior. The first parameter passed to this operation is an integer - |
2206 | ** positive to enable output for trigger programs, or zero to disable it, |
2207 | ** or negative to leave the setting unchanged. |
2208 | ** The second parameter is a pointer to an integer into which is written |
2209 | ** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if |
2210 | ** it is not disabled, 1 if it is. |
2211 | ** </dd> |
2212 | ** |
2213 | ** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt> |
2214 | ** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run |
2215 | ** [VACUUM] in order to reset a database back to an empty database |
2216 | ** with no schema and no content. The following process works even for |
2217 | ** a badly corrupted database file: |
2218 | ** <ol> |
2219 | ** <li> If the database connection is newly opened, make sure it has read the |
2220 | ** database schema by preparing then discarding some query against the |
2221 | ** database, or calling sqlite3_table_column_metadata(), ignoring any |
2222 | ** errors. This step is only necessary if the application desires to keep |
2223 | ** the database in WAL mode after the reset if it was in WAL mode before |
2224 | ** the reset. |
2225 | ** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0); |
2226 | ** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0); |
2227 | ** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0); |
2228 | ** </ol> |
2229 | ** Because resetting a database is destructive and irreversible, the |
2230 | ** process requires the use of this obscure API and multiple steps to help |
2231 | ** ensure that it does not happen by accident. |
2232 | ** |
2233 | ** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt> |
2234 | ** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the |
2235 | ** "defensive" flag for a database connection. When the defensive |
2236 | ** flag is enabled, language features that allow ordinary SQL to |
2237 | ** deliberately corrupt the database file are disabled. The disabled |
2238 | ** features include but are not limited to the following: |
2239 | ** <ul> |
2240 | ** <li> The [PRAGMA writable_schema=ON] statement. |
2241 | ** <li> The [PRAGMA journal_mode=OFF] statement. |
2242 | ** <li> Writes to the [sqlite_dbpage] virtual table. |
2243 | ** <li> Direct writes to [shadow tables]. |
2244 | ** </ul> |
2245 | ** </dd> |
2246 | ** |
2247 | ** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt> |
2248 | ** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the |
2249 | ** "writable_schema" flag. This has the same effect and is logically equivalent |
2250 | ** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF]. |
2251 | ** The first argument to this setting is an integer which is 0 to disable |
2252 | ** the writable_schema, positive to enable writable_schema, or negative to |
2253 | ** leave the setting unchanged. The second parameter is a pointer to an |
2254 | ** integer into which is written 0 or 1 to indicate whether the writable_schema |
2255 | ** is enabled or disabled following this call. |
2256 | ** </dd> |
2257 | ** |
2258 | ** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]] |
2259 | ** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt> |
2260 | ** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates |
2261 | ** the legacy behavior of the [ALTER TABLE RENAME] command such it |
2262 | ** behaves as it did prior to [version 3.24.0] (2018-06-04). See the |
2263 | ** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for |
2264 | ** additional information. This feature can also be turned on and off |
2265 | ** using the [PRAGMA legacy_alter_table] statement. |
2266 | ** </dd> |
2267 | ** |
2268 | ** [[SQLITE_DBCONFIG_DQS_DML]] |
2269 | ** <dt>SQLITE_DBCONFIG_DQS_DML</td> |
2270 | ** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates |
2271 | ** the legacy [double-quoted string literal] misfeature for DML statements |
2272 | ** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The |
2273 | ** default value of this setting is determined by the [-DSQLITE_DQS] |
2274 | ** compile-time option. |
2275 | ** </dd> |
2276 | ** |
2277 | ** [[SQLITE_DBCONFIG_DQS_DDL]] |
2278 | ** <dt>SQLITE_DBCONFIG_DQS_DDL</td> |
2279 | ** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates |
2280 | ** the legacy [double-quoted string literal] misfeature for DDL statements, |
2281 | ** such as CREATE TABLE and CREATE INDEX. The |
2282 | ** default value of this setting is determined by the [-DSQLITE_DQS] |
2283 | ** compile-time option. |
2284 | ** </dd> |
2285 | ** |
2286 | ** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]] |
2287 | ** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</td> |
2288 | ** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to |
2289 | ** assume that database schemas are untainted by malicious content. |
2290 | ** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite |
2291 | ** takes additional defensive steps to protect the application from harm |
2292 | ** including: |
2293 | ** <ul> |
2294 | ** <li> Prohibit the use of SQL functions inside triggers, views, |
2295 | ** CHECK constraints, DEFAULT clauses, expression indexes, |
2296 | ** partial indexes, or generated columns |
2297 | ** unless those functions are tagged with [SQLITE_INNOCUOUS]. |
2298 | ** <li> Prohibit the use of virtual tables inside of triggers or views |
2299 | ** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS]. |
2300 | ** </ul> |
2301 | ** This setting defaults to "on" for legacy compatibility, however |
2302 | ** all applications are advised to turn it off if possible. This setting |
2303 | ** can also be controlled using the [PRAGMA trusted_schema] statement. |
2304 | ** </dd> |
2305 | ** |
2306 | ** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]] |
2307 | ** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</td> |
2308 | ** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates |
2309 | ** the legacy file format flag. When activated, this flag causes all newly |
2310 | ** created database file to have a schema format version number (the 4-byte |
2311 | ** integer found at offset 44 into the database header) of 1. This in turn |
2312 | ** means that the resulting database file will be readable and writable by |
2313 | ** any SQLite version back to 3.0.0 ([dateof:3.0.0]). Without this setting, |
2314 | ** newly created databases are generally not understandable by SQLite versions |
2315 | ** prior to 3.3.0 ([dateof:3.3.0]). As these words are written, there |
2316 | ** is now scarcely any need to generated database files that are compatible |
2317 | ** all the way back to version 3.0.0, and so this setting is of little |
2318 | ** practical use, but is provided so that SQLite can continue to claim the |
2319 | ** ability to generate new database files that are compatible with version |
2320 | ** 3.0.0. |
2321 | ** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on, |
2322 | ** the [VACUUM] command will fail with an obscure error when attempting to |
2323 | ** process a table with generated columns and a descending index. This is |
2324 | ** not considered a bug since SQLite versions 3.3.0 and earlier do not support |
2325 | ** either generated columns or decending indexes. |
2326 | ** </dd> |
2327 | ** </dl> |
2328 | */ |
2329 | #define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */ |
2330 | #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ |
2331 | #define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */ |
2332 | #define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */ |
2333 | #define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */ |
2334 | #define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */ |
2335 | #define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */ |
2336 | #define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */ |
2337 | #define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */ |
2338 | #define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */ |
2339 | #define SQLITE_DBCONFIG_DEFENSIVE 1010 /* int int* */ |
2340 | #define SQLITE_DBCONFIG_WRITABLE_SCHEMA 1011 /* int int* */ |
2341 | #define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE 1012 /* int int* */ |
2342 | #define SQLITE_DBCONFIG_DQS_DML 1013 /* int int* */ |
2343 | #define SQLITE_DBCONFIG_DQS_DDL 1014 /* int int* */ |
2344 | #define SQLITE_DBCONFIG_ENABLE_VIEW 1015 /* int int* */ |
2345 | #define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT 1016 /* int int* */ |
2346 | #define SQLITE_DBCONFIG_TRUSTED_SCHEMA 1017 /* int int* */ |
2347 | #define SQLITE_DBCONFIG_MAX 1017 /* Largest DBCONFIG */ |
2348 | |
2349 | /* |
2350 | ** CAPI3REF: Enable Or Disable Extended Result Codes |
2351 | ** METHOD: sqlite3 |
2352 | ** |
2353 | ** ^The sqlite3_extended_result_codes() routine enables or disables the |
2354 | ** [extended result codes] feature of SQLite. ^The extended result |
2355 | ** codes are disabled by default for historical compatibility. |
2356 | */ |
2357 | SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff); |
2358 | |
2359 | /* |
2360 | ** CAPI3REF: Last Insert Rowid |
2361 | ** METHOD: sqlite3 |
2362 | ** |
2363 | ** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables) |
2364 | ** has a unique 64-bit signed |
2365 | ** integer key called the [ROWID | "rowid"]. ^The rowid is always available |
2366 | ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those |
2367 | ** names are not also used by explicitly declared columns. ^If |
2368 | ** the table has a column of type [INTEGER PRIMARY KEY] then that column |
2369 | ** is another alias for the rowid. |
2370 | ** |
2371 | ** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of |
2372 | ** the most recent successful [INSERT] into a rowid table or [virtual table] |
2373 | ** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not |
2374 | ** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred |
2375 | ** on the database connection D, then sqlite3_last_insert_rowid(D) returns |
2376 | ** zero. |
2377 | ** |
2378 | ** As well as being set automatically as rows are inserted into database |
2379 | ** tables, the value returned by this function may be set explicitly by |
2380 | ** [sqlite3_set_last_insert_rowid()] |
2381 | ** |
2382 | ** Some virtual table implementations may INSERT rows into rowid tables as |
2383 | ** part of committing a transaction (e.g. to flush data accumulated in memory |
2384 | ** to disk). In this case subsequent calls to this function return the rowid |
2385 | ** associated with these internal INSERT operations, which leads to |
2386 | ** unintuitive results. Virtual table implementations that do write to rowid |
2387 | ** tables in this way can avoid this problem by restoring the original |
2388 | ** rowid value using [sqlite3_set_last_insert_rowid()] before returning |
2389 | ** control to the user. |
2390 | ** |
2391 | ** ^(If an [INSERT] occurs within a trigger then this routine will |
2392 | ** return the [rowid] of the inserted row as long as the trigger is |
2393 | ** running. Once the trigger program ends, the value returned |
2394 | ** by this routine reverts to what it was before the trigger was fired.)^ |
2395 | ** |
2396 | ** ^An [INSERT] that fails due to a constraint violation is not a |
2397 | ** successful [INSERT] and does not change the value returned by this |
2398 | ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, |
2399 | ** and INSERT OR ABORT make no changes to the return value of this |
2400 | ** routine when their insertion fails. ^(When INSERT OR REPLACE |
2401 | ** encounters a constraint violation, it does not fail. The |
2402 | ** INSERT continues to completion after deleting rows that caused |
2403 | ** the constraint problem so INSERT OR REPLACE will always change |
2404 | ** the return value of this interface.)^ |
2405 | ** |
2406 | ** ^For the purposes of this routine, an [INSERT] is considered to |
2407 | ** be successful even if it is subsequently rolled back. |
2408 | ** |
2409 | ** This function is accessible to SQL statements via the |
2410 | ** [last_insert_rowid() SQL function]. |
2411 | ** |
2412 | ** If a separate thread performs a new [INSERT] on the same |
2413 | ** database connection while the [sqlite3_last_insert_rowid()] |
2414 | ** function is running and thus changes the last insert [rowid], |
2415 | ** then the value returned by [sqlite3_last_insert_rowid()] is |
2416 | ** unpredictable and might not equal either the old or the new |
2417 | ** last insert [rowid]. |
2418 | */ |
2419 | SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); |
2420 | |
2421 | /* |
2422 | ** CAPI3REF: Set the Last Insert Rowid value. |
2423 | ** METHOD: sqlite3 |
2424 | ** |
2425 | ** The sqlite3_set_last_insert_rowid(D, R) method allows the application to |
2426 | ** set the value returned by calling sqlite3_last_insert_rowid(D) to R |
2427 | ** without inserting a row into the database. |
2428 | */ |
2429 | SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64); |
2430 | |
2431 | /* |
2432 | ** CAPI3REF: Count The Number Of Rows Modified |
2433 | ** METHOD: sqlite3 |
2434 | ** |
2435 | ** ^This function returns the number of rows modified, inserted or |
2436 | ** deleted by the most recently completed INSERT, UPDATE or DELETE |
2437 | ** statement on the database connection specified by the only parameter. |
2438 | ** ^Executing any other type of SQL statement does not modify the value |
2439 | ** returned by this function. |
2440 | ** |
2441 | ** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are |
2442 | ** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], |
2443 | ** [foreign key actions] or [REPLACE] constraint resolution are not counted. |
2444 | ** |
2445 | ** Changes to a view that are intercepted by |
2446 | ** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value |
2447 | ** returned by sqlite3_changes() immediately after an INSERT, UPDATE or |
2448 | ** DELETE statement run on a view is always zero. Only changes made to real |
2449 | ** tables are counted. |
2450 | ** |
2451 | ** Things are more complicated if the sqlite3_changes() function is |
2452 | ** executed while a trigger program is running. This may happen if the |
2453 | ** program uses the [changes() SQL function], or if some other callback |
2454 | ** function invokes sqlite3_changes() directly. Essentially: |
2455 | ** |
2456 | ** <ul> |
2457 | ** <li> ^(Before entering a trigger program the value returned by |
2458 | ** sqlite3_changes() function is saved. After the trigger program |
2459 | ** has finished, the original value is restored.)^ |
2460 | ** |
2461 | ** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE |
2462 | ** statement sets the value returned by sqlite3_changes() |
2463 | ** upon completion as normal. Of course, this value will not include |
2464 | ** any changes performed by sub-triggers, as the sqlite3_changes() |
2465 | ** value will be saved and restored after each sub-trigger has run.)^ |
2466 | ** </ul> |
2467 | ** |
2468 | ** ^This means that if the changes() SQL function (or similar) is used |
2469 | ** by the first INSERT, UPDATE or DELETE statement within a trigger, it |
2470 | ** returns the value as set when the calling statement began executing. |
2471 | ** ^If it is used by the second or subsequent such statement within a trigger |
2472 | ** program, the value returned reflects the number of rows modified by the |
2473 | ** previous INSERT, UPDATE or DELETE statement within the same trigger. |
2474 | ** |
2475 | ** If a separate thread makes changes on the same database connection |
2476 | ** while [sqlite3_changes()] is running then the value returned |
2477 | ** is unpredictable and not meaningful. |
2478 | ** |
2479 | ** See also: |
2480 | ** <ul> |
2481 | ** <li> the [sqlite3_total_changes()] interface |
2482 | ** <li> the [count_changes pragma] |
2483 | ** <li> the [changes() SQL function] |
2484 | ** <li> the [data_version pragma] |
2485 | ** </ul> |
2486 | */ |
2487 | SQLITE_API int sqlite3_changes(sqlite3*); |
2488 | |
2489 | /* |
2490 | ** CAPI3REF: Total Number Of Rows Modified |
2491 | ** METHOD: sqlite3 |
2492 | ** |
2493 | ** ^This function returns the total number of rows inserted, modified or |
2494 | ** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed |
2495 | ** since the database connection was opened, including those executed as |
2496 | ** part of trigger programs. ^Executing any other type of SQL statement |
2497 | ** does not affect the value returned by sqlite3_total_changes(). |
2498 | ** |
2499 | ** ^Changes made as part of [foreign key actions] are included in the |
2500 | ** count, but those made as part of REPLACE constraint resolution are |
2501 | ** not. ^Changes to a view that are intercepted by INSTEAD OF triggers |
2502 | ** are not counted. |
2503 | ** |
2504 | ** The [sqlite3_total_changes(D)] interface only reports the number |
2505 | ** of rows that changed due to SQL statement run against database |
2506 | ** connection D. Any changes by other database connections are ignored. |
2507 | ** To detect changes against a database file from other database |
2508 | ** connections use the [PRAGMA data_version] command or the |
2509 | ** [SQLITE_FCNTL_DATA_VERSION] [file control]. |
2510 | ** |
2511 | ** If a separate thread makes changes on the same database connection |
2512 | ** while [sqlite3_total_changes()] is running then the value |
2513 | ** returned is unpredictable and not meaningful. |
2514 | ** |
2515 | ** See also: |
2516 | ** <ul> |
2517 | ** <li> the [sqlite3_changes()] interface |
2518 | ** <li> the [count_changes pragma] |
2519 | ** <li> the [changes() SQL function] |
2520 | ** <li> the [data_version pragma] |
2521 | ** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control] |
2522 | ** </ul> |
2523 | */ |
2524 | SQLITE_API int sqlite3_total_changes(sqlite3*); |
2525 | |
2526 | /* |
2527 | ** CAPI3REF: Interrupt A Long-Running Query |
2528 | ** METHOD: sqlite3 |
2529 | ** |
2530 | ** ^This function causes any pending database operation to abort and |
2531 | ** return at its earliest opportunity. This routine is typically |
2532 | ** called in response to a user action such as pressing "Cancel" |
2533 | ** or Ctrl-C where the user wants a long query operation to halt |
2534 | ** immediately. |
2535 | ** |
2536 | ** ^It is safe to call this routine from a thread different from the |
2537 | ** thread that is currently running the database operation. But it |
2538 | ** is not safe to call this routine with a [database connection] that |
2539 | ** is closed or might close before sqlite3_interrupt() returns. |
2540 | ** |
2541 | ** ^If an SQL operation is very nearly finished at the time when |
2542 | ** sqlite3_interrupt() is called, then it might not have an opportunity |
2543 | ** to be interrupted and might continue to completion. |
2544 | ** |
2545 | ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. |
2546 | ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE |
2547 | ** that is inside an explicit transaction, then the entire transaction |
2548 | ** will be rolled back automatically. |
2549 | ** |
2550 | ** ^The sqlite3_interrupt(D) call is in effect until all currently running |
2551 | ** SQL statements on [database connection] D complete. ^Any new SQL statements |
2552 | ** that are started after the sqlite3_interrupt() call and before the |
2553 | ** running statement count reaches zero are interrupted as if they had been |
2554 | ** running prior to the sqlite3_interrupt() call. ^New SQL statements |
2555 | ** that are started after the running statement count reaches zero are |
2556 | ** not effected by the sqlite3_interrupt(). |
2557 | ** ^A call to sqlite3_interrupt(D) that occurs when there are no running |
2558 | ** SQL statements is a no-op and has no effect on SQL statements |
2559 | ** that are started after the sqlite3_interrupt() call returns. |
2560 | */ |
2561 | SQLITE_API void sqlite3_interrupt(sqlite3*); |
2562 | |
2563 | /* |
2564 | ** CAPI3REF: Determine If An SQL Statement Is Complete |
2565 | ** |
2566 | ** These routines are useful during command-line input to determine if the |
2567 | ** currently entered text seems to form a complete SQL statement or |
2568 | ** if additional input is needed before sending the text into |
2569 | ** SQLite for parsing. ^These routines return 1 if the input string |
2570 | ** appears to be a complete SQL statement. ^A statement is judged to be |
2571 | ** complete if it ends with a semicolon token and is not a prefix of a |
2572 | ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within |
2573 | ** string literals or quoted identifier names or comments are not |
2574 | ** independent tokens (they are part of the token in which they are |
2575 | ** embedded) and thus do not count as a statement terminator. ^Whitespace |
2576 | ** and comments that follow the final semicolon are ignored. |
2577 | ** |
2578 | ** ^These routines return 0 if the statement is incomplete. ^If a |
2579 | ** memory allocation fails, then SQLITE_NOMEM is returned. |
2580 | ** |
2581 | ** ^These routines do not parse the SQL statements thus |
2582 | ** will not detect syntactically incorrect SQL. |
2583 | ** |
2584 | ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior |
2585 | ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked |
2586 | ** automatically by sqlite3_complete16(). If that initialization fails, |
2587 | ** then the return value from sqlite3_complete16() will be non-zero |
2588 | ** regardless of whether or not the input SQL is complete.)^ |
2589 | ** |
2590 | ** The input to [sqlite3_complete()] must be a zero-terminated |
2591 | ** UTF-8 string. |
2592 | ** |
2593 | ** The input to [sqlite3_complete16()] must be a zero-terminated |
2594 | ** UTF-16 string in native byte order. |
2595 | */ |
2596 | SQLITE_API int sqlite3_complete(const char *sql); |
2597 | SQLITE_API int sqlite3_complete16(const void *sql); |
2598 | |
2599 | /* |
2600 | ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors |
2601 | ** KEYWORDS: {busy-handler callback} {busy handler} |
2602 | ** METHOD: sqlite3 |
2603 | ** |
2604 | ** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X |
2605 | ** that might be invoked with argument P whenever |
2606 | ** an attempt is made to access a database table associated with |
2607 | ** [database connection] D when another thread |
2608 | ** or process has the table locked. |
2609 | ** The sqlite3_busy_handler() interface is used to implement |
2610 | ** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout]. |
2611 | ** |
2612 | ** ^If the busy callback is NULL, then [SQLITE_BUSY] |
2613 | ** is returned immediately upon encountering the lock. ^If the busy callback |
2614 | ** is not NULL, then the callback might be invoked with two arguments. |
2615 | ** |
2616 | ** ^The first argument to the busy handler is a copy of the void* pointer which |
2617 | ** is the third argument to sqlite3_busy_handler(). ^The second argument to |
2618 | ** the busy handler callback is the number of times that the busy handler has |
2619 | ** been invoked previously for the same locking event. ^If the |
2620 | ** busy callback returns 0, then no additional attempts are made to |
2621 | ** access the database and [SQLITE_BUSY] is returned |
2622 | ** to the application. |
2623 | ** ^If the callback returns non-zero, then another attempt |
2624 | ** is made to access the database and the cycle repeats. |
2625 | ** |
2626 | ** The presence of a busy handler does not guarantee that it will be invoked |
2627 | ** when there is lock contention. ^If SQLite determines that invoking the busy |
2628 | ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] |
2629 | ** to the application instead of invoking the |
2630 | ** busy handler. |
2631 | ** Consider a scenario where one process is holding a read lock that |
2632 | ** it is trying to promote to a reserved lock and |
2633 | ** a second process is holding a reserved lock that it is trying |
2634 | ** to promote to an exclusive lock. The first process cannot proceed |
2635 | ** because it is blocked by the second and the second process cannot |
2636 | ** proceed because it is blocked by the first. If both processes |
2637 | ** invoke the busy handlers, neither will make any progress. Therefore, |
2638 | ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this |
2639 | ** will induce the first process to release its read lock and allow |
2640 | ** the second process to proceed. |
2641 | ** |
2642 | ** ^The default busy callback is NULL. |
2643 | ** |
2644 | ** ^(There can only be a single busy handler defined for each |
2645 | ** [database connection]. Setting a new busy handler clears any |
2646 | ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()] |
2647 | ** or evaluating [PRAGMA busy_timeout=N] will change the |
2648 | ** busy handler and thus clear any previously set busy handler. |
2649 | ** |
2650 | ** The busy callback should not take any actions which modify the |
2651 | ** database connection that invoked the busy handler. In other words, |
2652 | ** the busy handler is not reentrant. Any such actions |
2653 | ** result in undefined behavior. |
2654 | ** |
2655 | ** A busy handler must not close the database connection |
2656 | ** or [prepared statement] that invoked the busy handler. |
2657 | */ |
2658 | SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*); |
2659 | |
2660 | /* |
2661 | ** CAPI3REF: Set A Busy Timeout |
2662 | ** METHOD: sqlite3 |
2663 | ** |
2664 | ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps |
2665 | ** for a specified amount of time when a table is locked. ^The handler |
2666 | ** will sleep multiple times until at least "ms" milliseconds of sleeping |
2667 | ** have accumulated. ^After at least "ms" milliseconds of sleeping, |
2668 | ** the handler returns 0 which causes [sqlite3_step()] to return |
2669 | ** [SQLITE_BUSY]. |
2670 | ** |
2671 | ** ^Calling this routine with an argument less than or equal to zero |
2672 | ** turns off all busy handlers. |
2673 | ** |
2674 | ** ^(There can only be a single busy handler for a particular |
2675 | ** [database connection] at any given moment. If another busy handler |
2676 | ** was defined (using [sqlite3_busy_handler()]) prior to calling |
2677 | ** this routine, that other busy handler is cleared.)^ |
2678 | ** |
2679 | ** See also: [PRAGMA busy_timeout] |
2680 | */ |
2681 | SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); |
2682 | |
2683 | /* |
2684 | ** CAPI3REF: Convenience Routines For Running Queries |
2685 | ** METHOD: sqlite3 |
2686 | ** |
2687 | ** This is a legacy interface that is preserved for backwards compatibility. |
2688 | ** Use of this interface is not recommended. |
2689 | ** |
2690 | ** Definition: A <b>result table</b> is memory data structure created by the |
2691 | ** [sqlite3_get_table()] interface. A result table records the |
2692 | ** complete query results from one or more queries. |
2693 | ** |
2694 | ** The table conceptually has a number of rows and columns. But |
2695 | ** these numbers are not part of the result table itself. These |
2696 | ** numbers are obtained separately. Let N be the number of rows |
2697 | ** and M be the number of columns. |
2698 | ** |
2699 | ** A result table is an array of pointers to zero-terminated UTF-8 strings. |
2700 | ** There are (N+1)*M elements in the array. The first M pointers point |
2701 | ** to zero-terminated strings that contain the names of the columns. |
2702 | ** The remaining entries all point to query results. NULL values result |
2703 | ** in NULL pointers. All other values are in their UTF-8 zero-terminated |
2704 | ** string representation as returned by [sqlite3_column_text()]. |
2705 | ** |
2706 | ** A result table might consist of one or more memory allocations. |
2707 | ** It is not safe to pass a result table directly to [sqlite3_free()]. |
2708 | ** A result table should be deallocated using [sqlite3_free_table()]. |
2709 | ** |
2710 | ** ^(As an example of the result table format, suppose a query result |
2711 | ** is as follows: |
2712 | ** |
2713 | ** <blockquote><pre> |
2714 | ** Name | Age |
2715 | ** ----------------------- |
2716 | ** Alice | 43 |
2717 | ** Bob | 28 |
2718 | ** Cindy | 21 |
2719 | ** </pre></blockquote> |
2720 | ** |
2721 | ** There are two columns (M==2) and three rows (N==3). Thus the |
2722 | ** result table has 8 entries. Suppose the result table is stored |
2723 | ** in an array named azResult. Then azResult holds this content: |
2724 | ** |
2725 | ** <blockquote><pre> |
2726 | ** azResult[0] = "Name"; |
2727 | ** azResult[1] = "Age"; |
2728 | ** azResult[2] = "Alice"; |
2729 | ** azResult[3] = "43"; |
2730 | ** azResult[4] = "Bob"; |
2731 | ** azResult[5] = "28"; |
2732 | ** azResult[6] = "Cindy"; |
2733 | ** azResult[7] = "21"; |
2734 | ** </pre></blockquote>)^ |
2735 | ** |
2736 | ** ^The sqlite3_get_table() function evaluates one or more |
2737 | ** semicolon-separated SQL statements in the zero-terminated UTF-8 |
2738 | ** string of its 2nd parameter and returns a result table to the |
2739 | ** pointer given in its 3rd parameter. |
2740 | ** |
2741 | ** After the application has finished with the result from sqlite3_get_table(), |
2742 | ** it must pass the result table pointer to sqlite3_free_table() in order to |
2743 | ** release the memory that was malloced. Because of the way the |
2744 | ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling |
2745 | ** function must not try to call [sqlite3_free()] directly. Only |
2746 | ** [sqlite3_free_table()] is able to release the memory properly and safely. |
2747 | ** |
2748 | ** The sqlite3_get_table() interface is implemented as a wrapper around |
2749 | ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access |
2750 | ** to any internal data structures of SQLite. It uses only the public |
2751 | ** interface defined here. As a consequence, errors that occur in the |
2752 | ** wrapper layer outside of the internal [sqlite3_exec()] call are not |
2753 | ** reflected in subsequent calls to [sqlite3_errcode()] or |
2754 | ** [sqlite3_errmsg()]. |
2755 | */ |
2756 | SQLITE_API int sqlite3_get_table( |
2757 | sqlite3 *db, /* An open database */ |
2758 | const char *zSql, /* SQL to be evaluated */ |
2759 | char ***pazResult, /* Results of the query */ |
2760 | int *pnRow, /* Number of result rows written here */ |
2761 | int *pnColumn, /* Number of result columns written here */ |
2762 | char **pzErrmsg /* Error msg written here */ |
2763 | ); |
2764 | SQLITE_API void sqlite3_free_table(char **result); |
2765 | |
2766 | /* |
2767 | ** CAPI3REF: Formatted String Printing Functions |
2768 | ** |
2769 | ** These routines are work-alikes of the "printf()" family of functions |
2770 | ** from the standard C library. |
2771 | ** These routines understand most of the common formatting options from |
2772 | ** the standard library printf() |
2773 | ** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]). |
2774 | ** See the [built-in printf()] documentation for details. |
2775 | ** |
2776 | ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their |
2777 | ** results into memory obtained from [sqlite3_malloc64()]. |
2778 | ** The strings returned by these two routines should be |
2779 | ** released by [sqlite3_free()]. ^Both routines return a |
2780 | ** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough |
2781 | ** memory to hold the resulting string. |
2782 | ** |
2783 | ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from |
2784 | ** the standard C library. The result is written into the |
2785 | ** buffer supplied as the second parameter whose size is given by |
2786 | ** the first parameter. Note that the order of the |
2787 | ** first two parameters is reversed from snprintf().)^ This is an |
2788 | ** historical accident that cannot be fixed without breaking |
2789 | ** backwards compatibility. ^(Note also that sqlite3_snprintf() |
2790 | ** returns a pointer to its buffer instead of the number of |
2791 | ** characters actually written into the buffer.)^ We admit that |
2792 | ** the number of characters written would be a more useful return |
2793 | ** value but we cannot change the implementation of sqlite3_snprintf() |
2794 | ** now without breaking compatibility. |
2795 | ** |
2796 | ** ^As long as the buffer size is greater than zero, sqlite3_snprintf() |
2797 | ** guarantees that the buffer is always zero-terminated. ^The first |
2798 | ** parameter "n" is the total size of the buffer, including space for |
2799 | ** the zero terminator. So the longest string that can be completely |
2800 | ** written will be n-1 characters. |
2801 | ** |
2802 | ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf(). |
2803 | ** |
2804 | ** See also: [built-in printf()], [printf() SQL function] |
2805 | */ |
2806 | SQLITE_API char *sqlite3_mprintf(const char*,...); |
2807 | SQLITE_API char *sqlite3_vmprintf(const char*, va_list); |
2808 | SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...); |
2809 | SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list); |
2810 | |
2811 | /* |
2812 | ** CAPI3REF: Memory Allocation Subsystem |
2813 | ** |
2814 | ** The SQLite core uses these three routines for all of its own |
2815 | ** internal memory allocation needs. "Core" in the previous sentence |
2816 | ** does not include operating-system specific [VFS] implementation. The |
2817 | ** Windows VFS uses native malloc() and free() for some operations. |
2818 | ** |
2819 | ** ^The sqlite3_malloc() routine returns a pointer to a block |
2820 | ** of memory at least N bytes in length, where N is the parameter. |
2821 | ** ^If sqlite3_malloc() is unable to obtain sufficient free |
2822 | ** memory, it returns a NULL pointer. ^If the parameter N to |
2823 | ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns |
2824 | ** a NULL pointer. |
2825 | ** |
2826 | ** ^The sqlite3_malloc64(N) routine works just like |
2827 | ** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead |
2828 | ** of a signed 32-bit integer. |
2829 | ** |
2830 | ** ^Calling sqlite3_free() with a pointer previously returned |
2831 | ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so |
2832 | ** that it might be reused. ^The sqlite3_free() routine is |
2833 | ** a no-op if is called with a NULL pointer. Passing a NULL pointer |
2834 | ** to sqlite3_free() is harmless. After being freed, memory |
2835 | ** should neither be read nor written. Even reading previously freed |
2836 | ** memory might result in a segmentation fault or other severe error. |
2837 | ** Memory corruption, a segmentation fault, or other severe error |
2838 | ** might result if sqlite3_free() is called with a non-NULL pointer that |
2839 | ** was not obtained from sqlite3_malloc() or sqlite3_realloc(). |
2840 | ** |
2841 | ** ^The sqlite3_realloc(X,N) interface attempts to resize a |
2842 | ** prior memory allocation X to be at least N bytes. |
2843 | ** ^If the X parameter to sqlite3_realloc(X,N) |
2844 | ** is a NULL pointer then its behavior is identical to calling |
2845 | ** sqlite3_malloc(N). |
2846 | ** ^If the N parameter to sqlite3_realloc(X,N) is zero or |
2847 | ** negative then the behavior is exactly the same as calling |
2848 | ** sqlite3_free(X). |
2849 | ** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation |
2850 | ** of at least N bytes in size or NULL if insufficient memory is available. |
2851 | ** ^If M is the size of the prior allocation, then min(N,M) bytes |
2852 | ** of the prior allocation are copied into the beginning of buffer returned |
2853 | ** by sqlite3_realloc(X,N) and the prior allocation is freed. |
2854 | ** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the |
2855 | ** prior allocation is not freed. |
2856 | ** |
2857 | ** ^The sqlite3_realloc64(X,N) interfaces works the same as |
2858 | ** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead |
2859 | ** of a 32-bit signed integer. |
2860 | ** |
2861 | ** ^If X is a memory allocation previously obtained from sqlite3_malloc(), |
2862 | ** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then |
2863 | ** sqlite3_msize(X) returns the size of that memory allocation in bytes. |
2864 | ** ^The value returned by sqlite3_msize(X) might be larger than the number |
2865 | ** of bytes requested when X was allocated. ^If X is a NULL pointer then |
2866 | ** sqlite3_msize(X) returns zero. If X points to something that is not |
2867 | ** the beginning of memory allocation, or if it points to a formerly |
2868 | ** valid memory allocation that has now been freed, then the behavior |
2869 | ** of sqlite3_msize(X) is undefined and possibly harmful. |
2870 | ** |
2871 | ** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(), |
2872 | ** sqlite3_malloc64(), and sqlite3_realloc64() |
2873 | ** is always aligned to at least an 8 byte boundary, or to a |
2874 | ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time |
2875 | ** option is used. |
2876 | ** |
2877 | ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] |
2878 | ** must be either NULL or else pointers obtained from a prior |
2879 | ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have |
2880 | ** not yet been released. |
2881 | ** |
2882 | ** The application must not read or write any part of |
2883 | ** a block of memory after it has been released using |
2884 | ** [sqlite3_free()] or [sqlite3_realloc()]. |
2885 | */ |
2886 | SQLITE_API void *sqlite3_malloc(int); |
2887 | SQLITE_API void *sqlite3_malloc64(sqlite3_uint64); |
2888 | SQLITE_API void *sqlite3_realloc(void*, int); |
2889 | SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64); |
2890 | SQLITE_API void sqlite3_free(void*); |
2891 | SQLITE_API sqlite3_uint64 sqlite3_msize(void*); |
2892 | |
2893 | /* |
2894 | ** CAPI3REF: Memory Allocator Statistics |
2895 | ** |
2896 | ** SQLite provides these two interfaces for reporting on the status |
2897 | ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] |
2898 | ** routines, which form the built-in memory allocation subsystem. |
2899 | ** |
2900 | ** ^The [sqlite3_memory_used()] routine returns the number of bytes |
2901 | ** of memory currently outstanding (malloced but not freed). |
2902 | ** ^The [sqlite3_memory_highwater()] routine returns the maximum |
2903 | ** value of [sqlite3_memory_used()] since the high-water mark |
2904 | ** was last reset. ^The values returned by [sqlite3_memory_used()] and |
2905 | ** [sqlite3_memory_highwater()] include any overhead |
2906 | ** added by SQLite in its implementation of [sqlite3_malloc()], |
2907 | ** but not overhead added by the any underlying system library |
2908 | ** routines that [sqlite3_malloc()] may call. |
2909 | ** |
2910 | ** ^The memory high-water mark is reset to the current value of |
2911 | ** [sqlite3_memory_used()] if and only if the parameter to |
2912 | ** [sqlite3_memory_highwater()] is true. ^The value returned |
2913 | ** by [sqlite3_memory_highwater(1)] is the high-water mark |
2914 | ** prior to the reset. |
2915 | */ |
2916 | SQLITE_API sqlite3_int64 sqlite3_memory_used(void); |
2917 | SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag); |
2918 | |
2919 | /* |
2920 | ** CAPI3REF: Pseudo-Random Number Generator |
2921 | ** |
2922 | ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to |
2923 | ** select random [ROWID | ROWIDs] when inserting new records into a table that |
2924 | ** already uses the largest possible [ROWID]. The PRNG is also used for |
2925 | ** the built-in random() and randomblob() SQL functions. This interface allows |
2926 | ** applications to access the same PRNG for other purposes. |
2927 | ** |
2928 | ** ^A call to this routine stores N bytes of randomness into buffer P. |
2929 | ** ^The P parameter can be a NULL pointer. |
2930 | ** |
2931 | ** ^If this routine has not been previously called or if the previous |
2932 | ** call had N less than one or a NULL pointer for P, then the PRNG is |
2933 | ** seeded using randomness obtained from the xRandomness method of |
2934 | ** the default [sqlite3_vfs] object. |
2935 | ** ^If the previous call to this routine had an N of 1 or more and a |
2936 | ** non-NULL P then the pseudo-randomness is generated |
2937 | ** internally and without recourse to the [sqlite3_vfs] xRandomness |
2938 | ** method. |
2939 | */ |
2940 | SQLITE_API void sqlite3_randomness(int N, void *P); |
2941 | |
2942 | /* |
2943 | ** CAPI3REF: Compile-Time Authorization Callbacks |
2944 | ** METHOD: sqlite3 |
2945 | ** KEYWORDS: {authorizer callback} |
2946 | ** |
2947 | ** ^This routine registers an authorizer callback with a particular |
2948 | ** [database connection], supplied in the first argument. |
2949 | ** ^The authorizer callback is invoked as SQL statements are being compiled |
2950 | ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], |
2951 | ** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()], |
2952 | ** and [sqlite3_prepare16_v3()]. ^At various |
2953 | ** points during the compilation process, as logic is being created |
2954 | ** to perform various actions, the authorizer callback is invoked to |
2955 | ** see if those actions are allowed. ^The authorizer callback should |
2956 | ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the |
2957 | ** specific action but allow the SQL statement to continue to be |
2958 | ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be |
2959 | ** rejected with an error. ^If the authorizer callback returns |
2960 | ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] |
2961 | ** then the [sqlite3_prepare_v2()] or equivalent call that triggered |
2962 | ** the authorizer will fail with an error message. |
2963 | ** |
2964 | ** When the callback returns [SQLITE_OK], that means the operation |
2965 | ** requested is ok. ^When the callback returns [SQLITE_DENY], the |
2966 | ** [sqlite3_prepare_v2()] or equivalent call that triggered the |
2967 | ** authorizer will fail with an error message explaining that |
2968 | ** access is denied. |
2969 | ** |
2970 | ** ^The first parameter to the authorizer callback is a copy of the third |
2971 | ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter |
2972 | ** to the callback is an integer [SQLITE_COPY | action code] that specifies |
2973 | ** the particular action to be authorized. ^The third through sixth parameters |
2974 | ** to the callback are either NULL pointers or zero-terminated strings |
2975 | ** that contain additional details about the action to be authorized. |
2976 | ** Applications must always be prepared to encounter a NULL pointer in any |
2977 | ** of the third through the sixth parameters of the authorization callback. |
2978 | ** |
2979 | ** ^If the action code is [SQLITE_READ] |
2980 | ** and the callback returns [SQLITE_IGNORE] then the |
2981 | ** [prepared statement] statement is constructed to substitute |
2982 | ** a NULL value in place of the table column that would have |
2983 | ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] |
2984 | ** return can be used to deny an untrusted user access to individual |
2985 | ** columns of a table. |
2986 | ** ^When a table is referenced by a [SELECT] but no column values are |
2987 | ** extracted from that table (for example in a query like |
2988 | ** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback |
2989 | ** is invoked once for that table with a column name that is an empty string. |
2990 | ** ^If the action code is [SQLITE_DELETE] and the callback returns |
2991 | ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the |
2992 | ** [truncate optimization] is disabled and all rows are deleted individually. |
2993 | ** |
2994 | ** An authorizer is used when [sqlite3_prepare | preparing] |
2995 | ** SQL statements from an untrusted source, to ensure that the SQL statements |
2996 | ** do not try to access data they are not allowed to see, or that they do not |
2997 | ** try to execute malicious statements that damage the database. For |
2998 | ** example, an application may allow a user to enter arbitrary |
2999 | ** SQL queries for evaluation by a database. But the application does |
3000 | ** not want the user to be able to make arbitrary changes to the |
3001 | ** database. An authorizer could then be put in place while the |
3002 | ** user-entered SQL is being [sqlite3_prepare | prepared] that |
3003 | ** disallows everything except [SELECT] statements. |
3004 | ** |
3005 | ** Applications that need to process SQL from untrusted sources |
3006 | ** might also consider lowering resource limits using [sqlite3_limit()] |
3007 | ** and limiting database size using the [max_page_count] [PRAGMA] |
3008 | ** in addition to using an authorizer. |
3009 | ** |
3010 | ** ^(Only a single authorizer can be in place on a database connection |
3011 | ** at a time. Each call to sqlite3_set_authorizer overrides the |
3012 | ** previous call.)^ ^Disable the authorizer by installing a NULL callback. |
3013 | ** The authorizer is disabled by default. |
3014 | ** |
3015 | ** The authorizer callback must not do anything that will modify |
3016 | ** the database connection that invoked the authorizer callback. |
3017 | ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their |
3018 | ** database connections for the meaning of "modify" in this paragraph. |
3019 | ** |
3020 | ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the |
3021 | ** statement might be re-prepared during [sqlite3_step()] due to a |
3022 | ** schema change. Hence, the application should ensure that the |
3023 | ** correct authorizer callback remains in place during the [sqlite3_step()]. |
3024 | ** |
3025 | ** ^Note that the authorizer callback is invoked only during |
3026 | ** [sqlite3_prepare()] or its variants. Authorization is not |
3027 | ** performed during statement evaluation in [sqlite3_step()], unless |
3028 | ** as stated in the previous paragraph, sqlite3_step() invokes |
3029 | ** sqlite3_prepare_v2() to reprepare a statement after a schema change. |
3030 | */ |
3031 | SQLITE_API int sqlite3_set_authorizer( |
3032 | sqlite3*, |
3033 | int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), |
3034 | void *pUserData |
3035 | ); |
3036 | |
3037 | /* |
3038 | ** CAPI3REF: Authorizer Return Codes |
3039 | ** |
3040 | ** The [sqlite3_set_authorizer | authorizer callback function] must |
3041 | ** return either [SQLITE_OK] or one of these two constants in order |
3042 | ** to signal SQLite whether or not the action is permitted. See the |
3043 | ** [sqlite3_set_authorizer | authorizer documentation] for additional |
3044 | ** information. |
3045 | ** |
3046 | ** Note that SQLITE_IGNORE is also used as a [conflict resolution mode] |
3047 | ** returned from the [sqlite3_vtab_on_conflict()] interface. |
3048 | */ |
3049 | #define SQLITE_DENY 1 /* Abort the SQL statement with an error */ |
3050 | #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ |
3051 | |
3052 | /* |
3053 | ** CAPI3REF: Authorizer Action Codes |
3054 | ** |
3055 | ** The [sqlite3_set_authorizer()] interface registers a callback function |
3056 | ** that is invoked to authorize certain SQL statement actions. The |
3057 | ** second parameter to the callback is an integer code that specifies |
3058 | ** what action is being authorized. These are the integer action codes that |
3059 | ** the authorizer callback may be passed. |
3060 | ** |
3061 | ** These action code values signify what kind of operation is to be |
3062 | ** authorized. The 3rd and 4th parameters to the authorization |
3063 | ** callback function will be parameters or NULL depending on which of these |
3064 | ** codes is used as the second parameter. ^(The 5th parameter to the |
3065 | ** authorizer callback is the name of the database ("main", "temp", |
3066 | ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback |
3067 | ** is the name of the inner-most trigger or view that is responsible for |
3068 | ** the access attempt or NULL if this access attempt is directly from |
3069 | ** top-level SQL code. |
3070 | */ |
3071 | /******************************************* 3rd ************ 4th ***********/ |
3072 | #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ |
3073 | #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ |
3074 | #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ |
3075 | #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ |
3076 | #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ |
3077 | #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ |
3078 | #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ |
3079 | #define SQLITE_CREATE_VIEW 8 /* View Name NULL */ |
3080 | #define SQLITE_DELETE 9 /* Table Name NULL */ |
3081 | #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ |
3082 | #define SQLITE_DROP_TABLE 11 /* Table Name NULL */ |
3083 | #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ |
3084 | #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ |
3085 | #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ |
3086 | #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ |
3087 | #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ |
3088 | #define SQLITE_DROP_VIEW 17 /* View Name NULL */ |
3089 | #define SQLITE_INSERT 18 /* Table Name NULL */ |
3090 | #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ |
3091 | #define SQLITE_READ 20 /* Table Name Column Name */ |
3092 | #define SQLITE_SELECT 21 /* NULL NULL */ |
3093 | #define SQLITE_TRANSACTION 22 /* Operation NULL */ |
3094 | #define SQLITE_UPDATE 23 /* Table Name Column Name */ |
3095 | #define SQLITE_ATTACH 24 /* Filename NULL */ |
3096 | #define SQLITE_DETACH 25 /* Database Name NULL */ |
3097 | #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ |
3098 | #define SQLITE_REINDEX 27 /* Index Name NULL */ |
3099 | #define SQLITE_ANALYZE 28 /* Table Name NULL */ |
3100 | #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ |
3101 | #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ |
3102 | #define SQLITE_FUNCTION 31 /* NULL Function Name */ |
3103 | #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ |
3104 | #define SQLITE_COPY 0 /* No longer used */ |
3105 | #define SQLITE_RECURSIVE 33 /* NULL NULL */ |
3106 | |
3107 | /* |
3108 | ** CAPI3REF: Tracing And Profiling Functions |
3109 | ** METHOD: sqlite3 |
3110 | ** |
3111 | ** These routines are deprecated. Use the [sqlite3_trace_v2()] interface |
3112 | ** instead of the routines described here. |
3113 | ** |
3114 | ** These routines register callback functions that can be used for |
3115 | ** tracing and profiling the execution of SQL statements. |
3116 | ** |
3117 | ** ^The callback function registered by sqlite3_trace() is invoked at |
3118 | ** various times when an SQL statement is being run by [sqlite3_step()]. |
3119 | ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the |
3120 | ** SQL statement text as the statement first begins executing. |
3121 | ** ^(Additional sqlite3_trace() callbacks might occur |
3122 | ** as each triggered subprogram is entered. The callbacks for triggers |
3123 | ** contain a UTF-8 SQL comment that identifies the trigger.)^ |
3124 | ** |
3125 | ** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit |
3126 | ** the length of [bound parameter] expansion in the output of sqlite3_trace(). |
3127 | ** |
3128 | ** ^The callback function registered by sqlite3_profile() is invoked |
3129 | ** as each SQL statement finishes. ^The profile callback contains |
3130 | ** the original statement text and an estimate of wall-clock time |
3131 | ** of how long that statement took to run. ^The profile callback |
3132 | ** time is in units of nanoseconds, however the current implementation |
3133 | ** is only capable of millisecond resolution so the six least significant |
3134 | ** digits in the time are meaningless. Future versions of SQLite |
3135 | ** might provide greater resolution on the profiler callback. Invoking |
3136 | ** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the |
3137 | ** profile callback. |
3138 | */ |
3139 | SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*, |
3140 | void(*xTrace)(void*,const char*), void*); |
3141 | SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*, |
3142 | void(*xProfile)(void*,const char*,sqlite3_uint64), void*); |
3143 | |
3144 | /* |
3145 | ** CAPI3REF: SQL Trace Event Codes |
3146 | ** KEYWORDS: SQLITE_TRACE |
3147 | ** |
3148 | ** These constants identify classes of events that can be monitored |
3149 | ** using the [sqlite3_trace_v2()] tracing logic. The M argument |
3150 | ** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of |
3151 | ** the following constants. ^The first argument to the trace callback |
3152 | ** is one of the following constants. |
3153 | ** |
3154 | ** New tracing constants may be added in future releases. |
3155 | ** |
3156 | ** ^A trace callback has four arguments: xCallback(T,C,P,X). |
3157 | ** ^The T argument is one of the integer type codes above. |
3158 | ** ^The C argument is a copy of the context pointer passed in as the |
3159 | ** fourth argument to [sqlite3_trace_v2()]. |
3160 | ** The P and X arguments are pointers whose meanings depend on T. |
3161 | ** |
3162 | ** <dl> |
3163 | ** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt> |
3164 | ** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement |
3165 | ** first begins running and possibly at other times during the |
3166 | ** execution of the prepared statement, such as at the start of each |
3167 | ** trigger subprogram. ^The P argument is a pointer to the |
3168 | ** [prepared statement]. ^The X argument is a pointer to a string which |
3169 | ** is the unexpanded SQL text of the prepared statement or an SQL comment |
3170 | ** that indicates the invocation of a trigger. ^The callback can compute |
3171 | ** the same text that would have been returned by the legacy [sqlite3_trace()] |
3172 | ** interface by using the X argument when X begins with "--" and invoking |
3173 | ** [sqlite3_expanded_sql(P)] otherwise. |
3174 | ** |
3175 | ** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt> |
3176 | ** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same |
3177 | ** information as is provided by the [sqlite3_profile()] callback. |
3178 | ** ^The P argument is a pointer to the [prepared statement] and the |
3179 | ** X argument points to a 64-bit integer which is the estimated of |
3180 | ** the number of nanosecond that the prepared statement took to run. |
3181 | ** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes. |
3182 | ** |
3183 | ** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt> |
3184 | ** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared |
3185 | ** statement generates a single row of result. |
3186 | ** ^The P argument is a pointer to the [prepared statement] and the |
3187 | ** X argument is unused. |
3188 | ** |
3189 | ** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt> |
3190 | ** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database |
3191 | ** connection closes. |
3192 | ** ^The P argument is a pointer to the [database connection] object |
3193 | ** and the X argument is unused. |
3194 | ** </dl> |
3195 | */ |
3196 | #define SQLITE_TRACE_STMT 0x01 |
3197 | #define SQLITE_TRACE_PROFILE 0x02 |
3198 | #define SQLITE_TRACE_ROW 0x04 |
3199 | #define SQLITE_TRACE_CLOSE 0x08 |
3200 | |
3201 | /* |
3202 | ** CAPI3REF: SQL Trace Hook |
3203 | ** METHOD: sqlite3 |
3204 | ** |
3205 | ** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback |
3206 | ** function X against [database connection] D, using property mask M |
3207 | ** and context pointer P. ^If the X callback is |
3208 | ** NULL or if the M mask is zero, then tracing is disabled. The |
3209 | ** M argument should be the bitwise OR-ed combination of |
3210 | ** zero or more [SQLITE_TRACE] constants. |
3211 | ** |
3212 | ** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides |
3213 | ** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2(). |
3214 | ** |
3215 | ** ^The X callback is invoked whenever any of the events identified by |
3216 | ** mask M occur. ^The integer return value from the callback is currently |
3217 | ** ignored, though this may change in future releases. Callback |
3218 | ** implementations should return zero to ensure future compatibility. |
3219 | ** |
3220 | ** ^A trace callback is invoked with four arguments: callback(T,C,P,X). |
3221 | ** ^The T argument is one of the [SQLITE_TRACE] |
3222 | ** constants to indicate why the callback was invoked. |
3223 | ** ^The C argument is a copy of the context pointer. |
3224 | ** The P and X arguments are pointers whose meanings depend on T. |
3225 | ** |
3226 | ** The sqlite3_trace_v2() interface is intended to replace the legacy |
3227 | ** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which |
3228 | ** are deprecated. |
3229 | */ |
3230 | SQLITE_API int sqlite3_trace_v2( |
3231 | sqlite3*, |
3232 | unsigned uMask, |
3233 | int(*xCallback)(unsigned,void*,void*,void*), |
3234 | void *pCtx |
3235 | ); |
3236 | |
3237 | /* |
3238 | ** CAPI3REF: Query Progress Callbacks |
3239 | ** METHOD: sqlite3 |
3240 | ** |
3241 | ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback |
3242 | ** function X to be invoked periodically during long running calls to |
3243 | ** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for |
3244 | ** database connection D. An example use for this |
3245 | ** interface is to keep a GUI updated during a large query. |
3246 | ** |
3247 | ** ^The parameter P is passed through as the only parameter to the |
3248 | ** callback function X. ^The parameter N is the approximate number of |
3249 | ** [virtual machine instructions] that are evaluated between successive |
3250 | ** invocations of the callback X. ^If N is less than one then the progress |
3251 | ** handler is disabled. |
3252 | ** |
3253 | ** ^Only a single progress handler may be defined at one time per |
3254 | ** [database connection]; setting a new progress handler cancels the |
3255 | ** old one. ^Setting parameter X to NULL disables the progress handler. |
3256 | ** ^The progress handler is also disabled by setting N to a value less |
3257 | ** than 1. |
3258 | ** |
3259 | ** ^If the progress callback returns non-zero, the operation is |
3260 | ** interrupted. This feature can be used to implement a |
3261 | ** "Cancel" button on a GUI progress dialog box. |
3262 | ** |
3263 | ** The progress handler callback must not do anything that will modify |
3264 | ** the database connection that invoked the progress handler. |
3265 | ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their |
3266 | ** database connections for the meaning of "modify" in this paragraph. |
3267 | ** |
3268 | */ |
3269 | SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); |
3270 | |
3271 | /* |
3272 | ** CAPI3REF: Opening A New Database Connection |
3273 | ** CONSTRUCTOR: sqlite3 |
3274 | ** |
3275 | ** ^These routines open an SQLite database file as specified by the |
3276 | ** filename argument. ^The filename argument is interpreted as UTF-8 for |
3277 | ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte |
3278 | ** order for sqlite3_open16(). ^(A [database connection] handle is usually |
3279 | ** returned in *ppDb, even if an error occurs. The only exception is that |
3280 | ** if SQLite is unable to allocate memory to hold the [sqlite3] object, |
3281 | ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] |
3282 | ** object.)^ ^(If the database is opened (and/or created) successfully, then |
3283 | ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The |
3284 | ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain |
3285 | ** an English language description of the error following a failure of any |
3286 | ** of the sqlite3_open() routines. |
3287 | ** |
3288 | ** ^The default encoding will be UTF-8 for databases created using |
3289 | ** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases |
3290 | ** created using sqlite3_open16() will be UTF-16 in the native byte order. |
3291 | ** |
3292 | ** Whether or not an error occurs when it is opened, resources |
3293 | ** associated with the [database connection] handle should be released by |
3294 | ** passing it to [sqlite3_close()] when it is no longer required. |
3295 | ** |
3296 | ** The sqlite3_open_v2() interface works like sqlite3_open() |
3297 | ** except that it accepts two additional parameters for additional control |
3298 | ** over the new database connection. ^(The flags parameter to |
3299 | ** sqlite3_open_v2() must include, at a minimum, one of the following |
3300 | ** three flag combinations:)^ |
3301 | ** |
3302 | ** <dl> |
3303 | ** ^(<dt>[SQLITE_OPEN_READONLY]</dt> |
3304 | ** <dd>The database is opened in read-only mode. If the database does not |
3305 | ** already exist, an error is returned.</dd>)^ |
3306 | ** |
3307 | ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt> |
3308 | ** <dd>The database is opened for reading and writing if possible, or reading |
3309 | ** only if the file is write protected by the operating system. In either |
3310 | ** case the database must already exist, otherwise an error is returned.</dd>)^ |
3311 | ** |
3312 | ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt> |
3313 | ** <dd>The database is opened for reading and writing, and is created if |
3314 | ** it does not already exist. This is the behavior that is always used for |
3315 | ** sqlite3_open() and sqlite3_open16().</dd>)^ |
3316 | ** </dl> |
3317 | ** |
3318 | ** In addition to the required flags, the following optional flags are |
3319 | ** also supported: |
3320 | ** |
3321 | ** <dl> |
3322 | ** ^(<dt>[SQLITE_OPEN_URI]</dt> |
3323 | ** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^ |
3324 | ** |
3325 | ** ^(<dt>[SQLITE_OPEN_MEMORY]</dt> |
3326 | ** <dd>The database will be opened as an in-memory database. The database |
3327 | ** is named by the "filename" argument for the purposes of cache-sharing, |
3328 | ** if shared cache mode is enabled, but the "filename" is otherwise ignored. |
3329 | ** </dd>)^ |
3330 | ** |
3331 | ** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt> |
3332 | ** <dd>The new database connection will use the "multi-thread" |
3333 | ** [threading mode].)^ This means that separate threads are allowed |
3334 | ** to use SQLite at the same time, as long as each thread is using |
3335 | ** a different [database connection]. |
3336 | ** |
3337 | ** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt> |
3338 | ** <dd>The new database connection will use the "serialized" |
3339 | ** [threading mode].)^ This means the multiple threads can safely |
3340 | ** attempt to use the same database connection at the same time. |
3341 | ** (Mutexes will block any actual concurrency, but in this mode |
3342 | ** there is no harm in trying.) |
3343 | ** |
3344 | ** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt> |
3345 | ** <dd>The database is opened [shared cache] enabled, overriding |
3346 | ** the default shared cache setting provided by |
3347 | ** [sqlite3_enable_shared_cache()].)^ |
3348 | ** |
3349 | ** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt> |
3350 | ** <dd>The database is opened [shared cache] disabled, overriding |
3351 | ** the default shared cache setting provided by |
3352 | ** [sqlite3_enable_shared_cache()].)^ |
3353 | ** |
3354 | ** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt> |
3355 | ** <dd>The database filename is not allowed to be a symbolic link</dd> |
3356 | ** </dl>)^ |
3357 | ** |
3358 | ** If the 3rd parameter to sqlite3_open_v2() is not one of the |
3359 | ** required combinations shown above optionally combined with other |
3360 | ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] |
3361 | ** then the behavior is undefined. |
3362 | ** |
3363 | ** ^The fourth parameter to sqlite3_open_v2() is the name of the |
3364 | ** [sqlite3_vfs] object that defines the operating system interface that |
3365 | ** the new database connection should use. ^If the fourth parameter is |
3366 | ** a NULL pointer then the default [sqlite3_vfs] object is used. |
3367 | ** |
3368 | ** ^If the filename is ":memory:", then a private, temporary in-memory database |
3369 | ** is created for the connection. ^This in-memory database will vanish when |
3370 | ** the database connection is closed. Future versions of SQLite might |
3371 | ** make use of additional special filenames that begin with the ":" character. |
3372 | ** It is recommended that when a database filename actually does begin with |
3373 | ** a ":" character you should prefix the filename with a pathname such as |
3374 | ** "./" to avoid ambiguity. |
3375 | ** |
3376 | ** ^If the filename is an empty string, then a private, temporary |
3377 | ** on-disk database will be created. ^This private database will be |
3378 | ** automatically deleted as soon as the database connection is closed. |
3379 | ** |
3380 | ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3> |
3381 | ** |
3382 | ** ^If [URI filename] interpretation is enabled, and the filename argument |
3383 | ** begins with "file:", then the filename is interpreted as a URI. ^URI |
3384 | ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is |
3385 | ** set in the third argument to sqlite3_open_v2(), or if it has |
3386 | ** been enabled globally using the [SQLITE_CONFIG_URI] option with the |
3387 | ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option. |
3388 | ** URI filename interpretation is turned off |
3389 | ** by default, but future releases of SQLite might enable URI filename |
3390 | ** interpretation by default. See "[URI filenames]" for additional |
3391 | ** information. |
3392 | ** |
3393 | ** URI filenames are parsed according to RFC 3986. ^If the URI contains an |
3394 | ** authority, then it must be either an empty string or the string |
3395 | ** "localhost". ^If the authority is not an empty string or "localhost", an |
3396 | ** error is returned to the caller. ^The fragment component of a URI, if |
3397 | ** present, is ignored. |
3398 | ** |
3399 | ** ^SQLite uses the path component of the URI as the name of the disk file |
3400 | ** which contains the database. ^If the path begins with a '/' character, |
3401 | ** then it is interpreted as an absolute path. ^If the path does not begin |
3402 | ** with a '/' (meaning that the authority section is omitted from the URI) |
3403 | ** then the path is interpreted as a relative path. |
3404 | ** ^(On windows, the first component of an absolute path |
3405 | ** is a drive specification (e.g. "C:").)^ |
3406 | ** |
3407 | ** [[core URI query parameters]] |
3408 | ** The query component of a URI may contain parameters that are interpreted |
3409 | ** either by SQLite itself, or by a [VFS | custom VFS implementation]. |
3410 | ** SQLite and its built-in [VFSes] interpret the |
3411 | ** following query parameters: |
3412 | ** |
3413 | ** <ul> |
3414 | ** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of |
3415 | ** a VFS object that provides the operating system interface that should |
3416 | ** be used to access the database file on disk. ^If this option is set to |
3417 | ** an empty string the default VFS object is used. ^Specifying an unknown |
3418 | ** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is |
3419 | ** present, then the VFS specified by the option takes precedence over |
3420 | ** the value passed as the fourth parameter to sqlite3_open_v2(). |
3421 | ** |
3422 | ** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw", |
3423 | ** "rwc", or "memory". Attempting to set it to any other value is |
3424 | ** an error)^. |
3425 | ** ^If "ro" is specified, then the database is opened for read-only |
3426 | ** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the |
3427 | ** third argument to sqlite3_open_v2(). ^If the mode option is set to |
3428 | ** "rw", then the database is opened for read-write (but not create) |
3429 | ** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had |
3430 | ** been set. ^Value "rwc" is equivalent to setting both |
3431 | ** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is |
3432 | ** set to "memory" then a pure [in-memory database] that never reads |
3433 | ** or writes from disk is used. ^It is an error to specify a value for |
3434 | ** the mode parameter that is less restrictive than that specified by |
3435 | ** the flags passed in the third parameter to sqlite3_open_v2(). |
3436 | ** |
3437 | ** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or |
3438 | ** "private". ^Setting it to "shared" is equivalent to setting the |
3439 | ** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to |
3440 | ** sqlite3_open_v2(). ^Setting the cache parameter to "private" is |
3441 | ** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit. |
3442 | ** ^If sqlite3_open_v2() is used and the "cache" parameter is present in |
3443 | ** a URI filename, its value overrides any behavior requested by setting |
3444 | ** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag. |
3445 | ** |
3446 | ** <li> <b>psow</b>: ^The psow parameter indicates whether or not the |
3447 | ** [powersafe overwrite] property does or does not apply to the |
3448 | ** storage media on which the database file resides. |
3449 | ** |
3450 | ** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter |
3451 | ** which if set disables file locking in rollback journal modes. This |
3452 | ** is useful for accessing a database on a filesystem that does not |
3453 | ** support locking. Caution: Database corruption might result if two |
3454 | ** or more processes write to the same database and any one of those |
3455 | ** processes uses nolock=1. |
3456 | ** |
3457 | ** <li> <b>immutable</b>: ^The immutable parameter is a boolean query |
3458 | ** parameter that indicates that the database file is stored on |
3459 | ** read-only media. ^When immutable is set, SQLite assumes that the |
3460 | ** database file cannot be changed, even by a process with higher |
3461 | ** privilege, and so the database is opened read-only and all locking |
3462 | ** and change detection is disabled. Caution: Setting the immutable |
3463 | ** property on a database file that does in fact change can result |
3464 | ** in incorrect query results and/or [SQLITE_CORRUPT] errors. |
3465 | ** See also: [SQLITE_IOCAP_IMMUTABLE]. |
3466 | ** |
3467 | ** </ul> |
3468 | ** |
3469 | ** ^Specifying an unknown parameter in the query component of a URI is not an |
3470 | ** error. Future versions of SQLite might understand additional query |
3471 | ** parameters. See "[query parameters with special meaning to SQLite]" for |
3472 | ** additional information. |
3473 | ** |
3474 | ** [[URI filename examples]] <h3>URI filename examples</h3> |
3475 | ** |
3476 | ** <table border="1" align=center cellpadding=5> |
3477 | ** <tr><th> URI filenames <th> Results |
3478 | ** <tr><td> file:data.db <td> |
3479 | ** Open the file "data.db" in the current directory. |
3480 | ** <tr><td> file:/home/fred/data.db<br> |
3481 | ** file:///home/fred/data.db <br> |
3482 | ** file://localhost/home/fred/data.db <br> <td> |
3483 | ** Open the database file "/home/fred/data.db". |
3484 | ** <tr><td> file://darkstar/home/fred/data.db <td> |
3485 | ** An error. "darkstar" is not a recognized authority. |
3486 | ** <tr><td style="white-space:nowrap"> |
3487 | ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db |
3488 | ** <td> Windows only: Open the file "data.db" on fred's desktop on drive |
3489 | ** C:. Note that the %20 escaping in this example is not strictly |
3490 | ** necessary - space characters can be used literally |
3491 | ** in URI filenames. |
3492 | ** <tr><td> file:data.db?mode=ro&cache=private <td> |
3493 | ** Open file "data.db" in the current directory for read-only access. |
3494 | ** Regardless of whether or not shared-cache mode is enabled by |
3495 | ** default, use a private cache. |
3496 | ** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td> |
3497 | ** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile" |
3498 | ** that uses dot-files in place of posix advisory locking. |
3499 | ** <tr><td> file:data.db?mode=readonly <td> |
3500 | ** An error. "readonly" is not a valid option for the "mode" parameter. |
3501 | ** </table> |
3502 | ** |
3503 | ** ^URI hexadecimal escape sequences (%HH) are supported within the path and |
3504 | ** query components of a URI. A hexadecimal escape sequence consists of a |
3505 | ** percent sign - "%" - followed by exactly two hexadecimal digits |
3506 | ** specifying an octet value. ^Before the path or query components of a |
3507 | ** URI filename are interpreted, they are encoded using UTF-8 and all |
3508 | ** hexadecimal escape sequences replaced by a single byte containing the |
3509 | ** corresponding octet. If this process generates an invalid UTF-8 encoding, |
3510 | ** the results are undefined. |
3511 | ** |
3512 | ** <b>Note to Windows users:</b> The encoding used for the filename argument |
3513 | ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever |
3514 | ** codepage is currently defined. Filenames containing international |
3515 | ** characters must be converted to UTF-8 prior to passing them into |
3516 | ** sqlite3_open() or sqlite3_open_v2(). |
3517 | ** |
3518 | ** <b>Note to Windows Runtime users:</b> The temporary directory must be set |
3519 | ** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various |
3520 | ** features that require the use of temporary files may fail. |
3521 | ** |
3522 | ** See also: [sqlite3_temp_directory] |
3523 | */ |
3524 | SQLITE_API int sqlite3_open( |
3525 | const char *filename, /* Database filename (UTF-8) */ |
3526 | sqlite3 **ppDb /* OUT: SQLite db handle */ |
3527 | ); |
3528 | SQLITE_API int sqlite3_open16( |
3529 | const void *filename, /* Database filename (UTF-16) */ |
3530 | sqlite3 **ppDb /* OUT: SQLite db handle */ |
3531 | ); |
3532 | SQLITE_API int sqlite3_open_v2( |
3533 | const char *filename, /* Database filename (UTF-8) */ |
3534 | sqlite3 **ppDb, /* OUT: SQLite db handle */ |
3535 | int flags, /* Flags */ |
3536 | const char *zVfs /* Name of VFS module to use */ |
3537 | ); |
3538 | |
3539 | /* |
3540 | ** CAPI3REF: Obtain Values For URI Parameters |
3541 | ** |
3542 | ** These are utility routines, useful to [VFS|custom VFS implementations], |
3543 | ** that check if a database file was a URI that contained a specific query |
3544 | ** parameter, and if so obtains the value of that query parameter. |
3545 | ** |
3546 | ** The first parameter to these interfaces (hereafter referred to |
3547 | ** as F) must be one of: |
3548 | ** <ul> |
3549 | ** <li> A database filename pointer created by the SQLite core and |
3550 | ** passed into the xOpen() method of a VFS implemention, or |
3551 | ** <li> A filename obtained from [sqlite3_db_filename()], or |
3552 | ** <li> A new filename constructed using [sqlite3_create_filename()]. |
3553 | ** </ul> |
3554 | ** If the F parameter is not one of the above, then the behavior is |
3555 | ** undefined and probably undesirable. Older versions of SQLite were |
3556 | ** more tolerant of invalid F parameters than newer versions. |
3557 | ** |
3558 | ** If F is a suitable filename (as described in the previous paragraph) |
3559 | ** and if P is the name of the query parameter, then |
3560 | ** sqlite3_uri_parameter(F,P) returns the value of the P |
3561 | ** parameter if it exists or a NULL pointer if P does not appear as a |
3562 | ** query parameter on F. If P is a query parameter of F and it |
3563 | ** has no explicit value, then sqlite3_uri_parameter(F,P) returns |
3564 | ** a pointer to an empty string. |
3565 | ** |
3566 | ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean |
3567 | ** parameter and returns true (1) or false (0) according to the value |
3568 | ** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the |
3569 | ** value of query parameter P is one of "yes", "true", or "on" in any |
3570 | ** case or if the value begins with a non-zero number. The |
3571 | ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of |
3572 | ** query parameter P is one of "no", "false", or "off" in any case or |
3573 | ** if the value begins with a numeric zero. If P is not a query |
3574 | ** parameter on F or if the value of P does not match any of the |
3575 | ** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0). |
3576 | ** |
3577 | ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a |
3578 | ** 64-bit signed integer and returns that integer, or D if P does not |
3579 | ** exist. If the value of P is something other than an integer, then |
3580 | ** zero is returned. |
3581 | ** |
3582 | ** The sqlite3_uri_key(F,N) returns a pointer to the name (not |
3583 | ** the value) of the N-th query parameter for filename F, or a NULL |
3584 | ** pointer if N is less than zero or greater than the number of query |
3585 | ** parameters minus 1. The N value is zero-based so N should be 0 to obtain |
3586 | ** the name of the first query parameter, 1 for the second parameter, and |
3587 | ** so forth. |
3588 | ** |
3589 | ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and |
3590 | ** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and |
3591 | ** is not a database file pathname pointer that the SQLite core passed |
3592 | ** into the xOpen VFS method, then the behavior of this routine is undefined |
3593 | ** and probably undesirable. |
3594 | ** |
3595 | ** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F |
3596 | ** parameter can also be the name of a rollback journal file or WAL file |
3597 | ** in addition to the main database file. Prior to version 3.31.0, these |
3598 | ** routines would only work if F was the name of the main database file. |
3599 | ** When the F parameter is the name of the rollback journal or WAL file, |
3600 | ** it has access to all the same query parameters as were found on the |
3601 | ** main database file. |
3602 | ** |
3603 | ** See the [URI filename] documentation for additional information. |
3604 | */ |
3605 | SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam); |
3606 | SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault); |
3607 | SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64); |
3608 | SQLITE_API const char *sqlite3_uri_key(const char *zFilename, int N); |
3609 | |
3610 | /* |
3611 | ** CAPI3REF: Translate filenames |
3612 | ** |
3613 | ** These routines are available to [VFS|custom VFS implementations] for |
3614 | ** translating filenames between the main database file, the journal file, |
3615 | ** and the WAL file. |
3616 | ** |
3617 | ** If F is the name of an sqlite database file, journal file, or WAL file |
3618 | ** passed by the SQLite core into the VFS, then sqlite3_filename_database(F) |
3619 | ** returns the name of the corresponding database file. |
3620 | ** |
3621 | ** If F is the name of an sqlite database file, journal file, or WAL file |
3622 | ** passed by the SQLite core into the VFS, or if F is a database filename |
3623 | ** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F) |
3624 | ** returns the name of the corresponding rollback journal file. |
3625 | ** |
3626 | ** If F is the name of an sqlite database file, journal file, or WAL file |
3627 | ** that was passed by the SQLite core into the VFS, or if F is a database |
3628 | ** filename obtained from [sqlite3_db_filename()], then |
3629 | ** sqlite3_filename_wal(F) returns the name of the corresponding |
3630 | ** WAL file. |
3631 | ** |
3632 | ** In all of the above, if F is not the name of a database, journal or WAL |
3633 | ** filename passed into the VFS from the SQLite core and F is not the |
3634 | ** return value from [sqlite3_db_filename()], then the result is |
3635 | ** undefined and is likely a memory access violation. |
3636 | */ |
3637 | SQLITE_API const char *sqlite3_filename_database(const char*); |
3638 | SQLITE_API const char *sqlite3_filename_journal(const char*); |
3639 | SQLITE_API const char *sqlite3_filename_wal(const char*); |
3640 | |
3641 | /* |
3642 | ** CAPI3REF: Database File Corresponding To A Journal |
3643 | ** |
3644 | ** ^If X is the name of a rollback or WAL-mode journal file that is |
3645 | ** passed into the xOpen method of [sqlite3_vfs], then |
3646 | ** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file] |
3647 | ** object that represents the main database file. |
3648 | ** |
3649 | ** This routine is intended for use in custom [VFS] implementations |
3650 | ** only. It is not a general-purpose interface. |
3651 | ** The argument sqlite3_file_object(X) must be a filename pointer that |
3652 | ** has been passed into [sqlite3_vfs].xOpen method where the |
3653 | ** flags parameter to xOpen contains one of the bits |
3654 | ** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL]. Any other use |
3655 | ** of this routine results in undefined and probably undesirable |
3656 | ** behavior. |
3657 | */ |
3658 | SQLITE_API sqlite3_file *sqlite3_database_file_object(const char*); |
3659 | |
3660 | /* |
3661 | ** CAPI3REF: Create and Destroy VFS Filenames |
3662 | ** |
3663 | ** These interfces are provided for use by [VFS shim] implementations and |
3664 | ** are not useful outside of that context. |
3665 | ** |
3666 | ** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of |
3667 | ** database filename D with corresponding journal file J and WAL file W and |
3668 | ** with N URI parameters key/values pairs in the array P. The result from |
3669 | ** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that |
3670 | ** is safe to pass to routines like: |
3671 | ** <ul> |
3672 | ** <li> [sqlite3_uri_parameter()], |
3673 | ** <li> [sqlite3_uri_boolean()], |
3674 | ** <li> [sqlite3_uri_int64()], |
3675 | ** <li> [sqlite3_uri_key()], |
3676 | ** <li> [sqlite3_filename_database()], |
3677 | ** <li> [sqlite3_filename_journal()], or |
3678 | ** <li> [sqlite3_filename_wal()]. |
3679 | ** </ul> |
3680 | ** If a memory allocation error occurs, sqlite3_create_filename() might |
3681 | ** return a NULL pointer. The memory obtained from sqlite3_create_filename(X) |
3682 | ** must be released by a corresponding call to sqlite3_free_filename(Y). |
3683 | ** |
3684 | ** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array |
3685 | ** of 2*N pointers to strings. Each pair of pointers in this array corresponds |
3686 | ** to a key and value for a query parameter. The P parameter may be a NULL |
3687 | ** pointer if N is zero. None of the 2*N pointers in the P array may be |
3688 | ** NULL pointers and key pointers should not be empty strings. |
3689 | ** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may |
3690 | ** be NULL pointers, though they can be empty strings. |
3691 | ** |
3692 | ** The sqlite3_free_filename(Y) routine releases a memory allocation |
3693 | ** previously obtained from sqlite3_create_filename(). Invoking |
3694 | ** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op. |
3695 | ** |
3696 | ** If the Y parameter to sqlite3_free_filename(Y) is anything other |
3697 | ** than a NULL pointer or a pointer previously acquired from |
3698 | ** sqlite3_create_filename(), then bad things such as heap |
3699 | ** corruption or segfaults may occur. The value Y should be |
3700 | ** used again after sqlite3_free_filename(Y) has been called. This means |
3701 | ** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y, |
3702 | ** then the corresponding [sqlite3_module.xClose() method should also be |
3703 | ** invoked prior to calling sqlite3_free_filename(Y). |
3704 | */ |
3705 | SQLITE_API char *sqlite3_create_filename( |
3706 | const char *zDatabase, |
3707 | const char *zJournal, |
3708 | const char *zWal, |
3709 | int nParam, |
3710 | const char **azParam |
3711 | ); |
3712 | SQLITE_API void sqlite3_free_filename(char*); |
3713 | |
3714 | /* |
3715 | ** CAPI3REF: Error Codes And Messages |
3716 | ** METHOD: sqlite3 |
3717 | ** |
3718 | ** ^If the most recent sqlite3_* API call associated with |
3719 | ** [database connection] D failed, then the sqlite3_errcode(D) interface |
3720 | ** returns the numeric [result code] or [extended result code] for that |
3721 | ** API call. |
3722 | ** ^The sqlite3_extended_errcode() |
3723 | ** interface is the same except that it always returns the |
3724 | ** [extended result code] even when extended result codes are |
3725 | ** disabled. |
3726 | ** |
3727 | ** The values returned by sqlite3_errcode() and/or |
3728 | ** sqlite3_extended_errcode() might change with each API call. |
3729 | ** Except, there are some interfaces that are guaranteed to never |
3730 | ** change the value of the error code. The error-code preserving |
3731 | ** interfaces are: |
3732 | ** |
3733 | ** <ul> |
3734 | ** <li> sqlite3_errcode() |
3735 | ** <li> sqlite3_extended_errcode() |
3736 | ** <li> sqlite3_errmsg() |
3737 | ** <li> sqlite3_errmsg16() |
3738 | ** </ul> |
3739 | ** |
3740 | ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language |
3741 | ** text that describes the error, as either UTF-8 or UTF-16 respectively. |
3742 | ** ^(Memory to hold the error message string is managed internally. |
3743 | ** The application does not need to worry about freeing the result. |
3744 | ** However, the error string might be overwritten or deallocated by |
3745 | ** subsequent calls to other SQLite interface functions.)^ |
3746 | ** |
3747 | ** ^The sqlite3_errstr() interface returns the English-language text |
3748 | ** that describes the [result code], as UTF-8. |
3749 | ** ^(Memory to hold the error message string is managed internally |
3750 | ** and must not be freed by the application)^. |
3751 | ** |
3752 | ** When the serialized [threading mode] is in use, it might be the |
3753 | ** case that a second error occurs on a separate thread in between |
3754 | ** the time of the first error and the call to these interfaces. |
3755 | ** When that happens, the second error will be reported since these |
3756 | ** interfaces always report the most recent result. To avoid |
3757 | ** this, each thread can obtain exclusive use of the [database connection] D |
3758 | ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning |
3759 | ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after |
3760 | ** all calls to the interfaces listed here are completed. |
3761 | ** |
3762 | ** If an interface fails with SQLITE_MISUSE, that means the interface |
3763 | ** was invoked incorrectly by the application. In that case, the |
3764 | ** error code and message may or may not be set. |
3765 | */ |
3766 | SQLITE_API int sqlite3_errcode(sqlite3 *db); |
3767 | SQLITE_API int sqlite3_extended_errcode(sqlite3 *db); |
3768 | SQLITE_API const char *sqlite3_errmsg(sqlite3*); |
3769 | SQLITE_API const void *sqlite3_errmsg16(sqlite3*); |
3770 | SQLITE_API const char *sqlite3_errstr(int); |
3771 | |
3772 | /* |
3773 | ** CAPI3REF: Prepared Statement Object |
3774 | ** KEYWORDS: {prepared statement} {prepared statements} |
3775 | ** |
3776 | ** An instance of this object represents a single SQL statement that |
3777 | ** has been compiled into binary form and is ready to be evaluated. |
3778 | ** |
3779 | ** Think of each SQL statement as a separate computer program. The |
3780 | ** original SQL text is source code. A prepared statement object |
3781 | ** is the compiled object code. All SQL must be converted into a |
3782 | ** prepared statement before it can be run. |
3783 | ** |
3784 | ** The life-cycle of a prepared statement object usually goes like this: |
3785 | ** |
3786 | ** <ol> |
3787 | ** <li> Create the prepared statement object using [sqlite3_prepare_v2()]. |
3788 | ** <li> Bind values to [parameters] using the sqlite3_bind_*() |
3789 | ** interfaces. |
3790 | ** <li> Run the SQL by calling [sqlite3_step()] one or more times. |
3791 | ** <li> Reset the prepared statement using [sqlite3_reset()] then go back |
3792 | ** to step 2. Do this zero or more times. |
3793 | ** <li> Destroy the object using [sqlite3_finalize()]. |
3794 | ** </ol> |
3795 | */ |
3796 | typedef struct sqlite3_stmt sqlite3_stmt; |
3797 | |
3798 | /* |
3799 | ** CAPI3REF: Run-time Limits |
3800 | ** METHOD: sqlite3 |
3801 | ** |
3802 | ** ^(This interface allows the size of various constructs to be limited |
3803 | ** on a connection by connection basis. The first parameter is the |
3804 | ** [database connection] whose limit is to be set or queried. The |
3805 | ** second parameter is one of the [limit categories] that define a |
3806 | ** class of constructs to be size limited. The third parameter is the |
3807 | ** new limit for that construct.)^ |
3808 | ** |
3809 | ** ^If the new limit is a negative number, the limit is unchanged. |
3810 | ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a |
3811 | ** [limits | hard upper bound] |
3812 | ** set at compile-time by a C preprocessor macro called |
3813 | ** [limits | SQLITE_MAX_<i>NAME</i>]. |
3814 | ** (The "_LIMIT_" in the name is changed to "_MAX_".))^ |
3815 | ** ^Attempts to increase a limit above its hard upper bound are |
3816 | ** silently truncated to the hard upper bound. |
3817 | ** |
3818 | ** ^Regardless of whether or not the limit was changed, the |
3819 | ** [sqlite3_limit()] interface returns the prior value of the limit. |
3820 | ** ^Hence, to find the current value of a limit without changing it, |
3821 | ** simply invoke this interface with the third parameter set to -1. |
3822 | ** |
3823 | ** Run-time limits are intended for use in applications that manage |
3824 | ** both their own internal database and also databases that are controlled |
3825 | ** by untrusted external sources. An example application might be a |
3826 | ** web browser that has its own databases for storing history and |
3827 | ** separate databases controlled by JavaScript applications downloaded |
3828 | ** off the Internet. The internal databases can be given the |
3829 | ** large, default limits. Databases managed by external sources can |
3830 | ** be given much smaller limits designed to prevent a denial of service |
3831 | ** attack. Developers might also want to use the [sqlite3_set_authorizer()] |
3832 | ** interface to further control untrusted SQL. The size of the database |
3833 | ** created by an untrusted script can be contained using the |
3834 | ** [max_page_count] [PRAGMA]. |
3835 | ** |
3836 | ** New run-time limit categories may be added in future releases. |
3837 | */ |
3838 | SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal); |
3839 | |
3840 | /* |
3841 | ** CAPI3REF: Run-Time Limit Categories |
3842 | ** KEYWORDS: {limit category} {*limit categories} |
3843 | ** |
3844 | ** These constants define various performance limits |
3845 | ** that can be lowered at run-time using [sqlite3_limit()]. |
3846 | ** The synopsis of the meanings of the various limits is shown below. |
3847 | ** Additional information is available at [limits | Limits in SQLite]. |
3848 | ** |
3849 | ** <dl> |
3850 | ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt> |
3851 | ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^ |
3852 | ** |
3853 | ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt> |
3854 | ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^ |
3855 | ** |
3856 | ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt> |
3857 | ** <dd>The maximum number of columns in a table definition or in the |
3858 | ** result set of a [SELECT] or the maximum number of columns in an index |
3859 | ** or in an ORDER BY or GROUP BY clause.</dd>)^ |
3860 | ** |
3861 | ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt> |
3862 | ** <dd>The maximum depth of the parse tree on any expression.</dd>)^ |
3863 | ** |
3864 | ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt> |
3865 | ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^ |
3866 | ** |
3867 | ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt> |
3868 | ** <dd>The maximum number of instructions in a virtual machine program |
3869 | ** used to implement an SQL statement. If [sqlite3_prepare_v2()] or |
3870 | ** the equivalent tries to allocate space for more than this many opcodes |
3871 | ** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^ |
3872 | ** |
3873 | ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt> |
3874 | ** <dd>The maximum number of arguments on a function.</dd>)^ |
3875 | ** |
3876 | ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt> |
3877 | ** <dd>The maximum number of [ATTACH | attached databases].)^</dd> |
3878 | ** |
3879 | ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] |
3880 | ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt> |
3881 | ** <dd>The maximum length of the pattern argument to the [LIKE] or |
3882 | ** [GLOB] operators.</dd>)^ |
3883 | ** |
3884 | ** [[SQLITE_LIMIT_VARIABLE_NUMBER]] |
3885 | ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt> |
3886 | ** <dd>The maximum index number of any [parameter] in an SQL statement.)^ |
3887 | ** |
3888 | ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt> |
3889 | ** <dd>The maximum depth of recursion for triggers.</dd>)^ |
3890 | ** |
3891 | ** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt> |
3892 | ** <dd>The maximum number of auxiliary worker threads that a single |
3893 | ** [prepared statement] may start.</dd>)^ |
3894 | ** </dl> |
3895 | */ |
3896 | #define SQLITE_LIMIT_LENGTH 0 |
3897 | #define SQLITE_LIMIT_SQL_LENGTH 1 |
3898 | #define SQLITE_LIMIT_COLUMN 2 |
3899 | #define SQLITE_LIMIT_EXPR_DEPTH 3 |
3900 | #define SQLITE_LIMIT_COMPOUND_SELECT 4 |
3901 | #define SQLITE_LIMIT_VDBE_OP 5 |
3902 | #define SQLITE_LIMIT_FUNCTION_ARG 6 |
3903 | #define SQLITE_LIMIT_ATTACHED 7 |
3904 | #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 |
3905 | #define SQLITE_LIMIT_VARIABLE_NUMBER 9 |
3906 | #define SQLITE_LIMIT_TRIGGER_DEPTH 10 |
3907 | #define SQLITE_LIMIT_WORKER_THREADS 11 |
3908 | |
3909 | /* |
3910 | ** CAPI3REF: Prepare Flags |
3911 | ** |
3912 | ** These constants define various flags that can be passed into |
3913 | ** "prepFlags" parameter of the [sqlite3_prepare_v3()] and |
3914 | ** [sqlite3_prepare16_v3()] interfaces. |
3915 | ** |
3916 | ** New flags may be added in future releases of SQLite. |
3917 | ** |
3918 | ** <dl> |
3919 | ** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt> |
3920 | ** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner |
3921 | ** that the prepared statement will be retained for a long time and |
3922 | ** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()] |
3923 | ** and [sqlite3_prepare16_v3()] assume that the prepared statement will |
3924 | ** be used just once or at most a few times and then destroyed using |
3925 | ** [sqlite3_finalize()] relatively soon. The current implementation acts |
3926 | ** on this hint by avoiding the use of [lookaside memory] so as not to |
3927 | ** deplete the limited store of lookaside memory. Future versions of |
3928 | ** SQLite may act on this hint differently. |
3929 | ** |
3930 | ** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt> |
3931 | ** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used |
3932 | ** to be required for any prepared statement that wanted to use the |
3933 | ** [sqlite3_normalized_sql()] interface. However, the |
3934 | ** [sqlite3_normalized_sql()] interface is now available to all |
3935 | ** prepared statements, regardless of whether or not they use this |
3936 | ** flag. |
3937 | ** |
3938 | ** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt> |
3939 | ** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler |
3940 | ** to return an error (error code SQLITE_ERROR) if the statement uses |
3941 | ** any virtual tables. |
3942 | ** </dl> |
3943 | */ |
3944 | #define SQLITE_PREPARE_PERSISTENT 0x01 |
3945 | #define SQLITE_PREPARE_NORMALIZE 0x02 |
3946 | #define SQLITE_PREPARE_NO_VTAB 0x04 |
3947 | |
3948 | /* |
3949 | ** CAPI3REF: Compiling An SQL Statement |
3950 | ** KEYWORDS: {SQL statement compiler} |
3951 | ** METHOD: sqlite3 |
3952 | ** CONSTRUCTOR: sqlite3_stmt |
3953 | ** |
3954 | ** To execute an SQL statement, it must first be compiled into a byte-code |
3955 | ** program using one of these routines. Or, in other words, these routines |
3956 | ** are constructors for the [prepared statement] object. |
3957 | ** |
3958 | ** The preferred routine to use is [sqlite3_prepare_v2()]. The |
3959 | ** [sqlite3_prepare()] interface is legacy and should be avoided. |
3960 | ** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used |
3961 | ** for special purposes. |
3962 | ** |
3963 | ** The use of the UTF-8 interfaces is preferred, as SQLite currently |
3964 | ** does all parsing using UTF-8. The UTF-16 interfaces are provided |
3965 | ** as a convenience. The UTF-16 interfaces work by converting the |
3966 | ** input text into UTF-8, then invoking the corresponding UTF-8 interface. |
3967 | ** |
3968 | ** The first argument, "db", is a [database connection] obtained from a |
3969 | ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or |
3970 | ** [sqlite3_open16()]. The database connection must not have been closed. |
3971 | ** |
3972 | ** The second argument, "zSql", is the statement to be compiled, encoded |
3973 | ** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(), |
3974 | ** and sqlite3_prepare_v3() |
3975 | ** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(), |
3976 | ** and sqlite3_prepare16_v3() use UTF-16. |
3977 | ** |
3978 | ** ^If the nByte argument is negative, then zSql is read up to the |
3979 | ** first zero terminator. ^If nByte is positive, then it is the |
3980 | ** number of bytes read from zSql. ^If nByte is zero, then no prepared |
3981 | ** statement is generated. |
3982 | ** If the caller knows that the supplied string is nul-terminated, then |
3983 | ** there is a small performance advantage to passing an nByte parameter that |
3984 | ** is the number of bytes in the input string <i>including</i> |
3985 | ** the nul-terminator. |
3986 | ** |
3987 | ** ^If pzTail is not NULL then *pzTail is made to point to the first byte |
3988 | ** past the end of the first SQL statement in zSql. These routines only |
3989 | ** compile the first statement in zSql, so *pzTail is left pointing to |
3990 | ** what remains uncompiled. |
3991 | ** |
3992 | ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be |
3993 | ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set |
3994 | ** to NULL. ^If the input text contains no SQL (if the input is an empty |
3995 | ** string or a comment) then *ppStmt is set to NULL. |
3996 | ** The calling procedure is responsible for deleting the compiled |
3997 | ** SQL statement using [sqlite3_finalize()] after it has finished with it. |
3998 | ** ppStmt may not be NULL. |
3999 | ** |
4000 | ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK]; |
4001 | ** otherwise an [error code] is returned. |
4002 | ** |
4003 | ** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(), |
4004 | ** and sqlite3_prepare16_v3() interfaces are recommended for all new programs. |
4005 | ** The older interfaces (sqlite3_prepare() and sqlite3_prepare16()) |
4006 | ** are retained for backwards compatibility, but their use is discouraged. |
4007 | ** ^In the "vX" interfaces, the prepared statement |
4008 | ** that is returned (the [sqlite3_stmt] object) contains a copy of the |
4009 | ** original SQL text. This causes the [sqlite3_step()] interface to |
4010 | ** behave differently in three ways: |
4011 | ** |
4012 | ** <ol> |
4013 | ** <li> |
4014 | ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it |
4015 | ** always used to do, [sqlite3_step()] will automatically recompile the SQL |
4016 | ** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY] |
4017 | ** retries will occur before sqlite3_step() gives up and returns an error. |
4018 | ** </li> |
4019 | ** |
4020 | ** <li> |
4021 | ** ^When an error occurs, [sqlite3_step()] will return one of the detailed |
4022 | ** [error codes] or [extended error codes]. ^The legacy behavior was that |
4023 | ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code |
4024 | ** and the application would have to make a second call to [sqlite3_reset()] |
4025 | ** in order to find the underlying cause of the problem. With the "v2" prepare |
4026 | ** interfaces, the underlying reason for the error is returned immediately. |
4027 | ** </li> |
4028 | ** |
4029 | ** <li> |
4030 | ** ^If the specific value bound to a [parameter | host parameter] in the |
4031 | ** WHERE clause might influence the choice of query plan for a statement, |
4032 | ** then the statement will be automatically recompiled, as if there had been |
4033 | ** a schema change, on the first [sqlite3_step()] call following any change |
4034 | ** to the [sqlite3_bind_text | bindings] of that [parameter]. |
4035 | ** ^The specific value of a WHERE-clause [parameter] might influence the |
4036 | ** choice of query plan if the parameter is the left-hand side of a [LIKE] |
4037 | ** or [GLOB] operator or if the parameter is compared to an indexed column |
4038 | ** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled. |
4039 | ** </li> |
4040 | ** </ol> |
4041 | ** |
4042 | ** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having |
4043 | ** the extra prepFlags parameter, which is a bit array consisting of zero or |
4044 | ** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The |
4045 | ** sqlite3_prepare_v2() interface works exactly the same as |
4046 | ** sqlite3_prepare_v3() with a zero prepFlags parameter. |
4047 | */ |
4048 | SQLITE_API int sqlite3_prepare( |
4049 | sqlite3 *db, /* Database handle */ |
4050 | const char *zSql, /* SQL statement, UTF-8 encoded */ |
4051 | int nByte, /* Maximum length of zSql in bytes. */ |
4052 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
4053 | const char **pzTail /* OUT: Pointer to unused portion of zSql */ |
4054 | ); |
4055 | SQLITE_API int sqlite3_prepare_v2( |
4056 | sqlite3 *db, /* Database handle */ |
4057 | const char *zSql, /* SQL statement, UTF-8 encoded */ |
4058 | int nByte, /* Maximum length of zSql in bytes. */ |
4059 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
4060 | const char **pzTail /* OUT: Pointer to unused portion of zSql */ |
4061 | ); |
4062 | SQLITE_API int sqlite3_prepare_v3( |
4063 | sqlite3 *db, /* Database handle */ |
4064 | const char *zSql, /* SQL statement, UTF-8 encoded */ |
4065 | int nByte, /* Maximum length of zSql in bytes. */ |
4066 | unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ |
4067 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
4068 | const char **pzTail /* OUT: Pointer to unused portion of zSql */ |
4069 | ); |
4070 | SQLITE_API int sqlite3_prepare16( |
4071 | sqlite3 *db, /* Database handle */ |
4072 | const void *zSql, /* SQL statement, UTF-16 encoded */ |
4073 | int nByte, /* Maximum length of zSql in bytes. */ |
4074 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
4075 | const void **pzTail /* OUT: Pointer to unused portion of zSql */ |
4076 | ); |
4077 | SQLITE_API int sqlite3_prepare16_v2( |
4078 | sqlite3 *db, /* Database handle */ |
4079 | const void *zSql, /* SQL statement, UTF-16 encoded */ |
4080 | int nByte, /* Maximum length of zSql in bytes. */ |
4081 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
4082 | const void **pzTail /* OUT: Pointer to unused portion of zSql */ |
4083 | ); |
4084 | SQLITE_API int sqlite3_prepare16_v3( |
4085 | sqlite3 *db, /* Database handle */ |
4086 | const void *zSql, /* SQL statement, UTF-16 encoded */ |
4087 | int nByte, /* Maximum length of zSql in bytes. */ |
4088 | unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ |
4089 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
4090 | const void **pzTail /* OUT: Pointer to unused portion of zSql */ |
4091 | ); |
4092 | |
4093 | /* |
4094 | ** CAPI3REF: Retrieving Statement SQL |
4095 | ** METHOD: sqlite3_stmt |
4096 | ** |
4097 | ** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8 |
4098 | ** SQL text used to create [prepared statement] P if P was |
4099 | ** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], |
4100 | ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. |
4101 | ** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8 |
4102 | ** string containing the SQL text of prepared statement P with |
4103 | ** [bound parameters] expanded. |
4104 | ** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8 |
4105 | ** string containing the normalized SQL text of prepared statement P. The |
4106 | ** semantics used to normalize a SQL statement are unspecified and subject |
4107 | ** to change. At a minimum, literal values will be replaced with suitable |
4108 | ** placeholders. |
4109 | ** |
4110 | ** ^(For example, if a prepared statement is created using the SQL |
4111 | ** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345 |
4112 | ** and parameter :xyz is unbound, then sqlite3_sql() will return |
4113 | ** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql() |
4114 | ** will return "SELECT 2345,NULL".)^ |
4115 | ** |
4116 | ** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory |
4117 | ** is available to hold the result, or if the result would exceed the |
4118 | ** the maximum string length determined by the [SQLITE_LIMIT_LENGTH]. |
4119 | ** |
4120 | ** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of |
4121 | ** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time |
4122 | ** option causes sqlite3_expanded_sql() to always return NULL. |
4123 | ** |
4124 | ** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P) |
4125 | ** are managed by SQLite and are automatically freed when the prepared |
4126 | ** statement is finalized. |
4127 | ** ^The string returned by sqlite3_expanded_sql(P), on the other hand, |
4128 | ** is obtained from [sqlite3_malloc()] and must be free by the application |
4129 | ** by passing it to [sqlite3_free()]. |
4130 | */ |
4131 | SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt); |
4132 | SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt); |
4133 | SQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt); |
4134 | |
4135 | /* |
4136 | ** CAPI3REF: Determine If An SQL Statement Writes The Database |
4137 | ** METHOD: sqlite3_stmt |
4138 | ** |
4139 | ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if |
4140 | ** and only if the [prepared statement] X makes no direct changes to |
4141 | ** the content of the database file. |
4142 | ** |
4143 | ** Note that [application-defined SQL functions] or |
4144 | ** [virtual tables] might change the database indirectly as a side effect. |
4145 | ** ^(For example, if an application defines a function "eval()" that |
4146 | ** calls [sqlite3_exec()], then the following SQL statement would |
4147 | ** change the database file through side-effects: |
4148 | ** |
4149 | ** <blockquote><pre> |
4150 | ** SELECT eval('DELETE FROM t1') FROM t2; |
4151 | ** </pre></blockquote> |
4152 | ** |
4153 | ** But because the [SELECT] statement does not change the database file |
4154 | ** directly, sqlite3_stmt_readonly() would still return true.)^ |
4155 | ** |
4156 | ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK], |
4157 | ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true, |
4158 | ** since the statements themselves do not actually modify the database but |
4159 | ** rather they control the timing of when other statements modify the |
4160 | ** database. ^The [ATTACH] and [DETACH] statements also cause |
4161 | ** sqlite3_stmt_readonly() to return true since, while those statements |
4162 | ** change the configuration of a database connection, they do not make |
4163 | ** changes to the content of the database files on disk. |
4164 | ** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since |
4165 | ** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and |
4166 | ** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so |
4167 | ** sqlite3_stmt_readonly() returns false for those commands. |
4168 | */ |
4169 | SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt); |
4170 | |
4171 | /* |
4172 | ** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement |
4173 | ** METHOD: sqlite3_stmt |
4174 | ** |
4175 | ** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the |
4176 | ** prepared statement S is an EXPLAIN statement, or 2 if the |
4177 | ** statement S is an EXPLAIN QUERY PLAN. |
4178 | ** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is |
4179 | ** an ordinary statement or a NULL pointer. |
4180 | */ |
4181 | SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt); |
4182 | |
4183 | /* |
4184 | ** CAPI3REF: Determine If A Prepared Statement Has Been Reset |
4185 | ** METHOD: sqlite3_stmt |
4186 | ** |
4187 | ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the |
4188 | ** [prepared statement] S has been stepped at least once using |
4189 | ** [sqlite3_step(S)] but has neither run to completion (returned |
4190 | ** [SQLITE_DONE] from [sqlite3_step(S)]) nor |
4191 | ** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S) |
4192 | ** interface returns false if S is a NULL pointer. If S is not a |
4193 | ** NULL pointer and is not a pointer to a valid [prepared statement] |
4194 | ** object, then the behavior is undefined and probably undesirable. |
4195 | ** |
4196 | ** This interface can be used in combination [sqlite3_next_stmt()] |
4197 | ** to locate all prepared statements associated with a database |
4198 | ** connection that are in need of being reset. This can be used, |
4199 | ** for example, in diagnostic routines to search for prepared |
4200 | ** statements that are holding a transaction open. |
4201 | */ |
4202 | SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*); |
4203 | |
4204 | /* |
4205 | ** CAPI3REF: Dynamically Typed Value Object |
4206 | ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} |
4207 | ** |
4208 | ** SQLite uses the sqlite3_value object to represent all values |
4209 | ** that can be stored in a database table. SQLite uses dynamic typing |
4210 | ** for the values it stores. ^Values stored in sqlite3_value objects |
4211 | ** can be integers, floating point values, strings, BLOBs, or NULL. |
4212 | ** |
4213 | ** An sqlite3_value object may be either "protected" or "unprotected". |
4214 | ** Some interfaces require a protected sqlite3_value. Other interfaces |
4215 | ** will accept either a protected or an unprotected sqlite3_value. |
4216 | ** Every interface that accepts sqlite3_value arguments specifies |
4217 | ** whether or not it requires a protected sqlite3_value. The |
4218 | ** [sqlite3_value_dup()] interface can be used to construct a new |
4219 | ** protected sqlite3_value from an unprotected sqlite3_value. |
4220 | ** |
4221 | ** The terms "protected" and "unprotected" refer to whether or not |
4222 | ** a mutex is held. An internal mutex is held for a protected |
4223 | ** sqlite3_value object but no mutex is held for an unprotected |
4224 | ** sqlite3_value object. If SQLite is compiled to be single-threaded |
4225 | ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) |
4226 | ** or if SQLite is run in one of reduced mutex modes |
4227 | ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] |
4228 | ** then there is no distinction between protected and unprotected |
4229 | ** sqlite3_value objects and they can be used interchangeably. However, |
4230 | ** for maximum code portability it is recommended that applications |
4231 | ** still make the distinction between protected and unprotected |
4232 | ** sqlite3_value objects even when not strictly required. |
4233 | ** |
4234 | ** ^The sqlite3_value objects that are passed as parameters into the |
4235 | ** implementation of [application-defined SQL functions] are protected. |
4236 | ** ^The sqlite3_value object returned by |
4237 | ** [sqlite3_column_value()] is unprotected. |
4238 | ** Unprotected sqlite3_value objects may only be used as arguments |
4239 | ** to [sqlite3_result_value()], [sqlite3_bind_value()], and |
4240 | ** [sqlite3_value_dup()]. |
4241 | ** The [sqlite3_value_blob | sqlite3_value_type()] family of |
4242 | ** interfaces require protected sqlite3_value objects. |
4243 | */ |
4244 | typedef struct sqlite3_value sqlite3_value; |
4245 | |
4246 | /* |
4247 | ** CAPI3REF: SQL Function Context Object |
4248 | ** |
4249 | ** The context in which an SQL function executes is stored in an |
4250 | ** sqlite3_context object. ^A pointer to an sqlite3_context object |
4251 | ** is always first parameter to [application-defined SQL functions]. |
4252 | ** The application-defined SQL function implementation will pass this |
4253 | ** pointer through into calls to [sqlite3_result_int | sqlite3_result()], |
4254 | ** [sqlite3_aggregate_context()], [sqlite3_user_data()], |
4255 | ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], |
4256 | ** and/or [sqlite3_set_auxdata()]. |
4257 | */ |
4258 | typedef struct sqlite3_context sqlite3_context; |
4259 | |
4260 | /* |
4261 | ** CAPI3REF: Binding Values To Prepared Statements |
4262 | ** KEYWORDS: {host parameter} {host parameters} {host parameter name} |
4263 | ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} |
4264 | ** METHOD: sqlite3_stmt |
4265 | ** |
4266 | ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants, |
4267 | ** literals may be replaced by a [parameter] that matches one of following |
4268 | ** templates: |
4269 | ** |
4270 | ** <ul> |
4271 | ** <li> ? |
4272 | ** <li> ?NNN |
4273 | ** <li> :VVV |
4274 | ** <li> @VVV |
4275 | ** <li> $VVV |
4276 | ** </ul> |
4277 | ** |
4278 | ** In the templates above, NNN represents an integer literal, |
4279 | ** and VVV represents an alphanumeric identifier.)^ ^The values of these |
4280 | ** parameters (also called "host parameter names" or "SQL parameters") |
4281 | ** can be set using the sqlite3_bind_*() routines defined here. |
4282 | ** |
4283 | ** ^The first argument to the sqlite3_bind_*() routines is always |
4284 | ** a pointer to the [sqlite3_stmt] object returned from |
4285 | ** [sqlite3_prepare_v2()] or its variants. |
4286 | ** |
4287 | ** ^The second argument is the index of the SQL parameter to be set. |
4288 | ** ^The leftmost SQL parameter has an index of 1. ^When the same named |
4289 | ** SQL parameter is used more than once, second and subsequent |
4290 | ** occurrences have the same index as the first occurrence. |
4291 | ** ^The index for named parameters can be looked up using the |
4292 | ** [sqlite3_bind_parameter_index()] API if desired. ^The index |
4293 | ** for "?NNN" parameters is the value of NNN. |
4294 | ** ^The NNN value must be between 1 and the [sqlite3_limit()] |
4295 | ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766). |
4296 | ** |
4297 | ** ^The third argument is the value to bind to the parameter. |
4298 | ** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16() |
4299 | ** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter |
4300 | ** is ignored and the end result is the same as sqlite3_bind_null(). |
4301 | ** ^If the third parameter to sqlite3_bind_text() is not NULL, then |
4302 | ** it should be a pointer to well-formed UTF8 text. |
4303 | ** ^If the third parameter to sqlite3_bind_text16() is not NULL, then |
4304 | ** it should be a pointer to well-formed UTF16 text. |
4305 | ** ^If the third parameter to sqlite3_bind_text64() is not NULL, then |
4306 | ** it should be a pointer to a well-formed unicode string that is |
4307 | ** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16 |
4308 | ** otherwise. |
4309 | ** |
4310 | ** [[byte-order determination rules]] ^The byte-order of |
4311 | ** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF) |
4312 | ** found in first character, which is removed, or in the absence of a BOM |
4313 | ** the byte order is the native byte order of the host |
4314 | ** machine for sqlite3_bind_text16() or the byte order specified in |
4315 | ** the 6th parameter for sqlite3_bind_text64().)^ |
4316 | ** ^If UTF16 input text contains invalid unicode |
4317 | ** characters, then SQLite might change those invalid characters |
4318 | ** into the unicode replacement character: U+FFFD. |
4319 | ** |
4320 | ** ^(In those routines that have a fourth argument, its value is the |
4321 | ** number of bytes in the parameter. To be clear: the value is the |
4322 | ** number of <u>bytes</u> in the value, not the number of characters.)^ |
4323 | ** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16() |
4324 | ** is negative, then the length of the string is |
4325 | ** the number of bytes up to the first zero terminator. |
4326 | ** If the fourth parameter to sqlite3_bind_blob() is negative, then |
4327 | ** the behavior is undefined. |
4328 | ** If a non-negative fourth parameter is provided to sqlite3_bind_text() |
4329 | ** or sqlite3_bind_text16() or sqlite3_bind_text64() then |
4330 | ** that parameter must be the byte offset |
4331 | ** where the NUL terminator would occur assuming the string were NUL |
4332 | ** terminated. If any NUL characters occurs at byte offsets less than |
4333 | ** the value of the fourth parameter then the resulting string value will |
4334 | ** contain embedded NULs. The result of expressions involving strings |
4335 | ** with embedded NULs is undefined. |
4336 | ** |
4337 | ** ^The fifth argument to the BLOB and string binding interfaces |
4338 | ** is a destructor used to dispose of the BLOB or |
4339 | ** string after SQLite has finished with it. ^The destructor is called |
4340 | ** to dispose of the BLOB or string even if the call to the bind API fails, |
4341 | ** except the destructor is not called if the third parameter is a NULL |
4342 | ** pointer or the fourth parameter is negative. |
4343 | ** ^If the fifth argument is |
4344 | ** the special value [SQLITE_STATIC], then SQLite assumes that the |
4345 | ** information is in static, unmanaged space and does not need to be freed. |
4346 | ** ^If the fifth argument has the value [SQLITE_TRANSIENT], then |
4347 | ** SQLite makes its own private copy of the data immediately, before |
4348 | ** the sqlite3_bind_*() routine returns. |
4349 | ** |
4350 | ** ^The sixth argument to sqlite3_bind_text64() must be one of |
4351 | ** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE] |
4352 | ** to specify the encoding of the text in the third parameter. If |
4353 | ** the sixth argument to sqlite3_bind_text64() is not one of the |
4354 | ** allowed values shown above, or if the text encoding is different |
4355 | ** from the encoding specified by the sixth parameter, then the behavior |
4356 | ** is undefined. |
4357 | ** |
4358 | ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that |
4359 | ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory |
4360 | ** (just an integer to hold its size) while it is being processed. |
4361 | ** Zeroblobs are intended to serve as placeholders for BLOBs whose |
4362 | ** content is later written using |
4363 | ** [sqlite3_blob_open | incremental BLOB I/O] routines. |
4364 | ** ^A negative value for the zeroblob results in a zero-length BLOB. |
4365 | ** |
4366 | ** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in |
4367 | ** [prepared statement] S to have an SQL value of NULL, but to also be |
4368 | ** associated with the pointer P of type T. ^D is either a NULL pointer or |
4369 | ** a pointer to a destructor function for P. ^SQLite will invoke the |
4370 | ** destructor D with a single argument of P when it is finished using |
4371 | ** P. The T parameter should be a static string, preferably a string |
4372 | ** literal. The sqlite3_bind_pointer() routine is part of the |
4373 | ** [pointer passing interface] added for SQLite 3.20.0. |
4374 | ** |
4375 | ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer |
4376 | ** for the [prepared statement] or with a prepared statement for which |
4377 | ** [sqlite3_step()] has been called more recently than [sqlite3_reset()], |
4378 | ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_() |
4379 | ** routine is passed a [prepared statement] that has been finalized, the |
4380 | ** result is undefined and probably harmful. |
4381 | ** |
4382 | ** ^Bindings are not cleared by the [sqlite3_reset()] routine. |
4383 | ** ^Unbound parameters are interpreted as NULL. |
4384 | ** |
4385 | ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an |
4386 | ** [error code] if anything goes wrong. |
4387 | ** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB |
4388 | ** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or |
4389 | ** [SQLITE_MAX_LENGTH]. |
4390 | ** ^[SQLITE_RANGE] is returned if the parameter |
4391 | ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails. |
4392 | ** |
4393 | ** See also: [sqlite3_bind_parameter_count()], |
4394 | ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. |
4395 | */ |
4396 | SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); |
4397 | SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64, |
4398 | void(*)(void*)); |
4399 | SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double); |
4400 | SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int); |
4401 | SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); |
4402 | SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int); |
4403 | SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*)); |
4404 | SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); |
4405 | SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64, |
4406 | void(*)(void*), unsigned char encoding); |
4407 | SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); |
4408 | SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*)); |
4409 | SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); |
4410 | SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64); |
4411 | |
4412 | /* |
4413 | ** CAPI3REF: Number Of SQL Parameters |
4414 | ** METHOD: sqlite3_stmt |
4415 | ** |
4416 | ** ^This routine can be used to find the number of [SQL parameters] |
4417 | ** in a [prepared statement]. SQL parameters are tokens of the |
4418 | ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as |
4419 | ** placeholders for values that are [sqlite3_bind_blob | bound] |
4420 | ** to the parameters at a later time. |
4421 | ** |
4422 | ** ^(This routine actually returns the index of the largest (rightmost) |
4423 | ** parameter. For all forms except ?NNN, this will correspond to the |
4424 | ** number of unique parameters. If parameters of the ?NNN form are used, |
4425 | ** there may be gaps in the list.)^ |
4426 | ** |
4427 | ** See also: [sqlite3_bind_blob|sqlite3_bind()], |
4428 | ** [sqlite3_bind_parameter_name()], and |
4429 | ** [sqlite3_bind_parameter_index()]. |
4430 | */ |
4431 | SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*); |
4432 | |
4433 | /* |
4434 | ** CAPI3REF: Name Of A Host Parameter |
4435 | ** METHOD: sqlite3_stmt |
4436 | ** |
4437 | ** ^The sqlite3_bind_parameter_name(P,N) interface returns |
4438 | ** the name of the N-th [SQL parameter] in the [prepared statement] P. |
4439 | ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" |
4440 | ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" |
4441 | ** respectively. |
4442 | ** In other words, the initial ":" or "$" or "@" or "?" |
4443 | ** is included as part of the name.)^ |
4444 | ** ^Parameters of the form "?" without a following integer have no name |
4445 | ** and are referred to as "nameless" or "anonymous parameters". |
4446 | ** |
4447 | ** ^The first host parameter has an index of 1, not 0. |
4448 | ** |
4449 | ** ^If the value N is out of range or if the N-th parameter is |
4450 | ** nameless, then NULL is returned. ^The returned string is |
4451 | ** always in UTF-8 encoding even if the named parameter was |
4452 | ** originally specified as UTF-16 in [sqlite3_prepare16()], |
4453 | ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. |
4454 | ** |
4455 | ** See also: [sqlite3_bind_blob|sqlite3_bind()], |
4456 | ** [sqlite3_bind_parameter_count()], and |
4457 | ** [sqlite3_bind_parameter_index()]. |
4458 | */ |
4459 | SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); |
4460 | |
4461 | /* |
4462 | ** CAPI3REF: Index Of A Parameter With A Given Name |
4463 | ** METHOD: sqlite3_stmt |
4464 | ** |
4465 | ** ^Return the index of an SQL parameter given its name. ^The |
4466 | ** index value returned is suitable for use as the second |
4467 | ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero |
4468 | ** is returned if no matching parameter is found. ^The parameter |
4469 | ** name must be given in UTF-8 even if the original statement |
4470 | ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or |
4471 | ** [sqlite3_prepare16_v3()]. |
4472 | ** |
4473 | ** See also: [sqlite3_bind_blob|sqlite3_bind()], |
4474 | ** [sqlite3_bind_parameter_count()], and |
4475 | ** [sqlite3_bind_parameter_name()]. |
4476 | */ |
4477 | SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); |
4478 | |
4479 | /* |
4480 | ** CAPI3REF: Reset All Bindings On A Prepared Statement |
4481 | ** METHOD: sqlite3_stmt |
4482 | ** |
4483 | ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset |
4484 | ** the [sqlite3_bind_blob | bindings] on a [prepared statement]. |
4485 | ** ^Use this routine to reset all host parameters to NULL. |
4486 | */ |
4487 | SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*); |
4488 | |
4489 | /* |
4490 | ** CAPI3REF: Number Of Columns In A Result Set |
4491 | ** METHOD: sqlite3_stmt |
4492 | ** |
4493 | ** ^Return the number of columns in the result set returned by the |
4494 | ** [prepared statement]. ^If this routine returns 0, that means the |
4495 | ** [prepared statement] returns no data (for example an [UPDATE]). |
4496 | ** ^However, just because this routine returns a positive number does not |
4497 | ** mean that one or more rows of data will be returned. ^A SELECT statement |
4498 | ** will always have a positive sqlite3_column_count() but depending on the |
4499 | ** WHERE clause constraints and the table content, it might return no rows. |
4500 | ** |
4501 | ** See also: [sqlite3_data_count()] |
4502 | */ |
4503 | SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt); |
4504 | |
4505 | /* |
4506 | ** CAPI3REF: Column Names In A Result Set |
4507 | ** METHOD: sqlite3_stmt |
4508 | ** |
4509 | ** ^These routines return the name assigned to a particular column |
4510 | ** in the result set of a [SELECT] statement. ^The sqlite3_column_name() |
4511 | ** interface returns a pointer to a zero-terminated UTF-8 string |
4512 | ** and sqlite3_column_name16() returns a pointer to a zero-terminated |
4513 | ** UTF-16 string. ^The first parameter is the [prepared statement] |
4514 | ** that implements the [SELECT] statement. ^The second parameter is the |
4515 | ** column number. ^The leftmost column is number 0. |
4516 | ** |
4517 | ** ^The returned string pointer is valid until either the [prepared statement] |
4518 | ** is destroyed by [sqlite3_finalize()] or until the statement is automatically |
4519 | ** reprepared by the first call to [sqlite3_step()] for a particular run |
4520 | ** or until the next call to |
4521 | ** sqlite3_column_name() or sqlite3_column_name16() on the same column. |
4522 | ** |
4523 | ** ^If sqlite3_malloc() fails during the processing of either routine |
4524 | ** (for example during a conversion from UTF-8 to UTF-16) then a |
4525 | ** NULL pointer is returned. |
4526 | ** |
4527 | ** ^The name of a result column is the value of the "AS" clause for |
4528 | ** that column, if there is an AS clause. If there is no AS clause |
4529 | ** then the name of the column is unspecified and may change from |
4530 | ** one release of SQLite to the next. |
4531 | */ |
4532 | SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N); |
4533 | SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N); |
4534 | |
4535 | /* |
4536 | ** CAPI3REF: Source Of Data In A Query Result |
4537 | ** METHOD: sqlite3_stmt |
4538 | ** |
4539 | ** ^These routines provide a means to determine the database, table, and |
4540 | ** table column that is the origin of a particular result column in |
4541 | ** [SELECT] statement. |
4542 | ** ^The name of the database or table or column can be returned as |
4543 | ** either a UTF-8 or UTF-16 string. ^The _database_ routines return |
4544 | ** the database name, the _table_ routines return the table name, and |
4545 | ** the origin_ routines return the column name. |
4546 | ** ^The returned string is valid until the [prepared statement] is destroyed |
4547 | ** using [sqlite3_finalize()] or until the statement is automatically |
4548 | ** reprepared by the first call to [sqlite3_step()] for a particular run |
4549 | ** or until the same information is requested |
4550 | ** again in a different encoding. |
4551 | ** |
4552 | ** ^The names returned are the original un-aliased names of the |
4553 | ** database, table, and column. |
4554 | ** |
4555 | ** ^The first argument to these interfaces is a [prepared statement]. |
4556 | ** ^These functions return information about the Nth result column returned by |
4557 | ** the statement, where N is the second function argument. |
4558 | ** ^The left-most column is column 0 for these routines. |
4559 | ** |
4560 | ** ^If the Nth column returned by the statement is an expression or |
4561 | ** subquery and is not a column value, then all of these functions return |
4562 | ** NULL. ^These routines might also return NULL if a memory allocation error |
4563 | ** occurs. ^Otherwise, they return the name of the attached database, table, |
4564 | ** or column that query result column was extracted from. |
4565 | ** |
4566 | ** ^As with all other SQLite APIs, those whose names end with "16" return |
4567 | ** UTF-16 encoded strings and the other functions return UTF-8. |
4568 | ** |
4569 | ** ^These APIs are only available if the library was compiled with the |
4570 | ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol. |
4571 | ** |
4572 | ** If two or more threads call one or more |
4573 | ** [sqlite3_column_database_name | column metadata interfaces] |
4574 | ** for the same [prepared statement] and result column |
4575 | ** at the same time then the results are undefined. |
4576 | */ |
4577 | SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int); |
4578 | SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int); |
4579 | SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int); |
4580 | SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int); |
4581 | SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int); |
4582 | SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); |
4583 | |
4584 | /* |
4585 | ** CAPI3REF: Declared Datatype Of A Query Result |
4586 | ** METHOD: sqlite3_stmt |
4587 | ** |
4588 | ** ^(The first parameter is a [prepared statement]. |
4589 | ** If this statement is a [SELECT] statement and the Nth column of the |
4590 | ** returned result set of that [SELECT] is a table column (not an |
4591 | ** expression or subquery) then the declared type of the table |
4592 | ** column is returned.)^ ^If the Nth column of the result set is an |
4593 | ** expression or subquery, then a NULL pointer is returned. |
4594 | ** ^The returned string is always UTF-8 encoded. |
4595 | ** |
4596 | ** ^(For example, given the database schema: |
4597 | ** |
4598 | ** CREATE TABLE t1(c1 VARIANT); |
4599 | ** |
4600 | ** and the following statement to be compiled: |
4601 | ** |
4602 | ** SELECT c1 + 1, c1 FROM t1; |
4603 | ** |
4604 | ** this routine would return the string "VARIANT" for the second result |
4605 | ** column (i==1), and a NULL pointer for the first result column (i==0).)^ |
4606 | ** |
4607 | ** ^SQLite uses dynamic run-time typing. ^So just because a column |
4608 | ** is declared to contain a particular type does not mean that the |
4609 | ** data stored in that column is of the declared type. SQLite is |
4610 | ** strongly typed, but the typing is dynamic not static. ^Type |
4611 | ** is associated with individual values, not with the containers |
4612 | ** used to hold those values. |
4613 | */ |
4614 | SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int); |
4615 | SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int); |
4616 | |
4617 | /* |
4618 | ** CAPI3REF: Evaluate An SQL Statement |
4619 | ** METHOD: sqlite3_stmt |
4620 | ** |
4621 | ** After a [prepared statement] has been prepared using any of |
4622 | ** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()], |
4623 | ** or [sqlite3_prepare16_v3()] or one of the legacy |
4624 | ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function |
4625 | ** must be called one or more times to evaluate the statement. |
4626 | ** |
4627 | ** The details of the behavior of the sqlite3_step() interface depend |
4628 | ** on whether the statement was prepared using the newer "vX" interfaces |
4629 | ** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()], |
4630 | ** [sqlite3_prepare16_v2()] or the older legacy |
4631 | ** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the |
4632 | ** new "vX" interface is recommended for new applications but the legacy |
4633 | ** interface will continue to be supported. |
4634 | ** |
4635 | ** ^In the legacy interface, the return value will be either [SQLITE_BUSY], |
4636 | ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. |
4637 | ** ^With the "v2" interface, any of the other [result codes] or |
4638 | ** [extended result codes] might be returned as well. |
4639 | ** |
4640 | ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the |
4641 | ** database locks it needs to do its job. ^If the statement is a [COMMIT] |
4642 | ** or occurs outside of an explicit transaction, then you can retry the |
4643 | ** statement. If the statement is not a [COMMIT] and occurs within an |
4644 | ** explicit transaction then you should rollback the transaction before |
4645 | ** continuing. |
4646 | ** |
4647 | ** ^[SQLITE_DONE] means that the statement has finished executing |
4648 | ** successfully. sqlite3_step() should not be called again on this virtual |
4649 | ** machine without first calling [sqlite3_reset()] to reset the virtual |
4650 | ** machine back to its initial state. |
4651 | ** |
4652 | ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW] |
4653 | ** is returned each time a new row of data is ready for processing by the |
4654 | ** caller. The values may be accessed using the [column access functions]. |
4655 | ** sqlite3_step() is called again to retrieve the next row of data. |
4656 | ** |
4657 | ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint |
4658 | ** violation) has occurred. sqlite3_step() should not be called again on |
4659 | ** the VM. More information may be found by calling [sqlite3_errmsg()]. |
4660 | ** ^With the legacy interface, a more specific error code (for example, |
4661 | ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) |
4662 | ** can be obtained by calling [sqlite3_reset()] on the |
4663 | ** [prepared statement]. ^In the "v2" interface, |
4664 | ** the more specific error code is returned directly by sqlite3_step(). |
4665 | ** |
4666 | ** [SQLITE_MISUSE] means that the this routine was called inappropriately. |
4667 | ** Perhaps it was called on a [prepared statement] that has |
4668 | ** already been [sqlite3_finalize | finalized] or on one that had |
4669 | ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could |
4670 | ** be the case that the same database connection is being used by two or |
4671 | ** more threads at the same moment in time. |
4672 | ** |
4673 | ** For all versions of SQLite up to and including 3.6.23.1, a call to |
4674 | ** [sqlite3_reset()] was required after sqlite3_step() returned anything |
4675 | ** other than [SQLITE_ROW] before any subsequent invocation of |
4676 | ** sqlite3_step(). Failure to reset the prepared statement using |
4677 | ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from |
4678 | ** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1], |
4679 | ** sqlite3_step() began |
4680 | ** calling [sqlite3_reset()] automatically in this circumstance rather |
4681 | ** than returning [SQLITE_MISUSE]. This is not considered a compatibility |
4682 | ** break because any application that ever receives an SQLITE_MISUSE error |
4683 | ** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option |
4684 | ** can be used to restore the legacy behavior. |
4685 | ** |
4686 | ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step() |
4687 | ** API always returns a generic error code, [SQLITE_ERROR], following any |
4688 | ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call |
4689 | ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the |
4690 | ** specific [error codes] that better describes the error. |
4691 | ** We admit that this is a goofy design. The problem has been fixed |
4692 | ** with the "v2" interface. If you prepare all of your SQL statements |
4693 | ** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()] |
4694 | ** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead |
4695 | ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, |
4696 | ** then the more specific [error codes] are returned directly |
4697 | ** by sqlite3_step(). The use of the "vX" interfaces is recommended. |
4698 | */ |
4699 | SQLITE_API int sqlite3_step(sqlite3_stmt*); |
4700 | |
4701 | /* |
4702 | ** CAPI3REF: Number of columns in a result set |
4703 | ** METHOD: sqlite3_stmt |
4704 | ** |
4705 | ** ^The sqlite3_data_count(P) interface returns the number of columns in the |
4706 | ** current row of the result set of [prepared statement] P. |
4707 | ** ^If prepared statement P does not have results ready to return |
4708 | ** (via calls to the [sqlite3_column_int | sqlite3_column()] family of |
4709 | ** interfaces) then sqlite3_data_count(P) returns 0. |
4710 | ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer. |
4711 | ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to |
4712 | ** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P) |
4713 | ** will return non-zero if previous call to [sqlite3_step](P) returned |
4714 | ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum] |
4715 | ** where it always returns zero since each step of that multi-step |
4716 | ** pragma returns 0 columns of data. |
4717 | ** |
4718 | ** See also: [sqlite3_column_count()] |
4719 | */ |
4720 | SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt); |
4721 | |
4722 | /* |
4723 | ** CAPI3REF: Fundamental Datatypes |
4724 | ** KEYWORDS: SQLITE_TEXT |
4725 | ** |
4726 | ** ^(Every value in SQLite has one of five fundamental datatypes: |
4727 | ** |
4728 | ** <ul> |
4729 | ** <li> 64-bit signed integer |
4730 | ** <li> 64-bit IEEE floating point number |
4731 | ** <li> string |
4732 | ** <li> BLOB |
4733 | ** <li> NULL |
4734 | ** </ul>)^ |
4735 | ** |
4736 | ** These constants are codes for each of those types. |
4737 | ** |
4738 | ** Note that the SQLITE_TEXT constant was also used in SQLite version 2 |
4739 | ** for a completely different meaning. Software that links against both |
4740 | ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not |
4741 | ** SQLITE_TEXT. |
4742 | */ |
4743 | #define SQLITE_INTEGER 1 |
4744 | #define SQLITE_FLOAT 2 |
4745 | #define SQLITE_BLOB 4 |
4746 | #define SQLITE_NULL 5 |
4747 | #ifdef SQLITE_TEXT |
4748 | # undef SQLITE_TEXT |
4749 | #else |
4750 | # define SQLITE_TEXT 3 |
4751 | #endif |
4752 | #define SQLITE3_TEXT 3 |
4753 | |
4754 | /* |
4755 | ** CAPI3REF: Result Values From A Query |
4756 | ** KEYWORDS: {column access functions} |
4757 | ** METHOD: sqlite3_stmt |
4758 | ** |
4759 | ** <b>Summary:</b> |
4760 | ** <blockquote><table border=0 cellpadding=0 cellspacing=0> |
4761 | ** <tr><td><b>sqlite3_column_blob</b><td>→<td>BLOB result |
4762 | ** <tr><td><b>sqlite3_column_double</b><td>→<td>REAL result |
4763 | ** <tr><td><b>sqlite3_column_int</b><td>→<td>32-bit INTEGER result |
4764 | ** <tr><td><b>sqlite3_column_int64</b><td>→<td>64-bit INTEGER result |
4765 | ** <tr><td><b>sqlite3_column_text</b><td>→<td>UTF-8 TEXT result |
4766 | ** <tr><td><b>sqlite3_column_text16</b><td>→<td>UTF-16 TEXT result |
4767 | ** <tr><td><b>sqlite3_column_value</b><td>→<td>The result as an |
4768 | ** [sqlite3_value|unprotected sqlite3_value] object. |
4769 | ** <tr><td> <td> <td> |
4770 | ** <tr><td><b>sqlite3_column_bytes</b><td>→<td>Size of a BLOB |
4771 | ** or a UTF-8 TEXT result in bytes |
4772 | ** <tr><td><b>sqlite3_column_bytes16 </b> |
4773 | ** <td>→ <td>Size of UTF-16 |
4774 | ** TEXT in bytes |
4775 | ** <tr><td><b>sqlite3_column_type</b><td>→<td>Default |
4776 | ** datatype of the result |
4777 | ** </table></blockquote> |
4778 | ** |
4779 | ** <b>Details:</b> |
4780 | ** |
4781 | ** ^These routines return information about a single column of the current |
4782 | ** result row of a query. ^In every case the first argument is a pointer |
4783 | ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] |
4784 | ** that was returned from [sqlite3_prepare_v2()] or one of its variants) |
4785 | ** and the second argument is the index of the column for which information |
4786 | ** should be returned. ^The leftmost column of the result set has the index 0. |
4787 | ** ^The number of columns in the result can be determined using |
4788 | ** [sqlite3_column_count()]. |
4789 | ** |
4790 | ** If the SQL statement does not currently point to a valid row, or if the |
4791 | ** column index is out of range, the result is undefined. |
4792 | ** These routines may only be called when the most recent call to |
4793 | ** [sqlite3_step()] has returned [SQLITE_ROW] and neither |
4794 | ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. |
4795 | ** If any of these routines are called after [sqlite3_reset()] or |
4796 | ** [sqlite3_finalize()] or after [sqlite3_step()] has returned |
4797 | ** something other than [SQLITE_ROW], the results are undefined. |
4798 | ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] |
4799 | ** are called from a different thread while any of these routines |
4800 | ** are pending, then the results are undefined. |
4801 | ** |
4802 | ** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16) |
4803 | ** each return the value of a result column in a specific data format. If |
4804 | ** the result column is not initially in the requested format (for example, |
4805 | ** if the query returns an integer but the sqlite3_column_text() interface |
4806 | ** is used to extract the value) then an automatic type conversion is performed. |
4807 | ** |
4808 | ** ^The sqlite3_column_type() routine returns the |
4809 | ** [SQLITE_INTEGER | datatype code] for the initial data type |
4810 | ** of the result column. ^The returned value is one of [SQLITE_INTEGER], |
4811 | ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. |
4812 | ** The return value of sqlite3_column_type() can be used to decide which |
4813 | ** of the first six interface should be used to extract the column value. |
4814 | ** The value returned by sqlite3_column_type() is only meaningful if no |
4815 | ** automatic type conversions have occurred for the value in question. |
4816 | ** After a type conversion, the result of calling sqlite3_column_type() |
4817 | ** is undefined, though harmless. Future |
4818 | ** versions of SQLite may change the behavior of sqlite3_column_type() |
4819 | ** following a type conversion. |
4820 | ** |
4821 | ** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes() |
4822 | ** or sqlite3_column_bytes16() interfaces can be used to determine the size |
4823 | ** of that BLOB or string. |
4824 | ** |
4825 | ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() |
4826 | ** routine returns the number of bytes in that BLOB or string. |
4827 | ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts |
4828 | ** the string to UTF-8 and then returns the number of bytes. |
4829 | ** ^If the result is a numeric value then sqlite3_column_bytes() uses |
4830 | ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns |
4831 | ** the number of bytes in that string. |
4832 | ** ^If the result is NULL, then sqlite3_column_bytes() returns zero. |
4833 | ** |
4834 | ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16() |
4835 | ** routine returns the number of bytes in that BLOB or string. |
4836 | ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts |
4837 | ** the string to UTF-16 and then returns the number of bytes. |
4838 | ** ^If the result is a numeric value then sqlite3_column_bytes16() uses |
4839 | ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns |
4840 | ** the number of bytes in that string. |
4841 | ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero. |
4842 | ** |
4843 | ** ^The values returned by [sqlite3_column_bytes()] and |
4844 | ** [sqlite3_column_bytes16()] do not include the zero terminators at the end |
4845 | ** of the string. ^For clarity: the values returned by |
4846 | ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of |
4847 | ** bytes in the string, not the number of characters. |
4848 | ** |
4849 | ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(), |
4850 | ** even empty strings, are always zero-terminated. ^The return |
4851 | ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer. |
4852 | ** |
4853 | ** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an |
4854 | ** [unprotected sqlite3_value] object. In a multithreaded environment, |
4855 | ** an unprotected sqlite3_value object may only be used safely with |
4856 | ** [sqlite3_bind_value()] and [sqlite3_result_value()]. |
4857 | ** If the [unprotected sqlite3_value] object returned by |
4858 | ** [sqlite3_column_value()] is used in any other way, including calls |
4859 | ** to routines like [sqlite3_value_int()], [sqlite3_value_text()], |
4860 | ** or [sqlite3_value_bytes()], the behavior is not threadsafe. |
4861 | ** Hence, the sqlite3_column_value() interface |
4862 | ** is normally only useful within the implementation of |
4863 | ** [application-defined SQL functions] or [virtual tables], not within |
4864 | ** top-level application code. |
4865 | ** |
4866 | ** The these routines may attempt to convert the datatype of the result. |
4867 | ** ^For example, if the internal representation is FLOAT and a text result |
4868 | ** is requested, [sqlite3_snprintf()] is used internally to perform the |
4869 | ** conversion automatically. ^(The following table details the conversions |
4870 | ** that are applied: |
4871 | ** |
4872 | ** <blockquote> |
4873 | ** <table border="1"> |
4874 | ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion |
4875 | ** |
4876 | ** <tr><td> NULL <td> INTEGER <td> Result is 0 |
4877 | ** <tr><td> NULL <td> FLOAT <td> Result is 0.0 |
4878 | ** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer |
4879 | ** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer |
4880 | ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float |
4881 | ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer |
4882 | ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT |
4883 | ** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER |
4884 | ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float |
4885 | ** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB |
4886 | ** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER |
4887 | ** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL |
4888 | ** <tr><td> TEXT <td> BLOB <td> No change |
4889 | ** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER |
4890 | ** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL |
4891 | ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed |
4892 | ** </table> |
4893 | ** </blockquote>)^ |
4894 | ** |
4895 | ** Note that when type conversions occur, pointers returned by prior |
4896 | ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or |
4897 | ** sqlite3_column_text16() may be invalidated. |
4898 | ** Type conversions and pointer invalidations might occur |
4899 | ** in the following cases: |
4900 | ** |
4901 | ** <ul> |
4902 | ** <li> The initial content is a BLOB and sqlite3_column_text() or |
4903 | ** sqlite3_column_text16() is called. A zero-terminator might |
4904 | ** need to be added to the string.</li> |
4905 | ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or |
4906 | ** sqlite3_column_text16() is called. The content must be converted |
4907 | ** to UTF-16.</li> |
4908 | ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or |
4909 | ** sqlite3_column_text() is called. The content must be converted |
4910 | ** to UTF-8.</li> |
4911 | ** </ul> |
4912 | ** |
4913 | ** ^Conversions between UTF-16be and UTF-16le are always done in place and do |
4914 | ** not invalidate a prior pointer, though of course the content of the buffer |
4915 | ** that the prior pointer references will have been modified. Other kinds |
4916 | ** of conversion are done in place when it is possible, but sometimes they |
4917 | ** are not possible and in those cases prior pointers are invalidated. |
4918 | ** |
4919 | ** The safest policy is to invoke these routines |
4920 | ** in one of the following ways: |
4921 | ** |
4922 | ** <ul> |
4923 | ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> |
4924 | ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> |
4925 | ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> |
4926 | ** </ul> |
4927 | ** |
4928 | ** In other words, you should call sqlite3_column_text(), |
4929 | ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result |
4930 | ** into the desired format, then invoke sqlite3_column_bytes() or |
4931 | ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls |
4932 | ** to sqlite3_column_text() or sqlite3_column_blob() with calls to |
4933 | ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() |
4934 | ** with calls to sqlite3_column_bytes(). |
4935 | ** |
4936 | ** ^The pointers returned are valid until a type conversion occurs as |
4937 | ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or |
4938 | ** [sqlite3_finalize()] is called. ^The memory space used to hold strings |
4939 | ** and BLOBs is freed automatically. Do not pass the pointers returned |
4940 | ** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into |
4941 | ** [sqlite3_free()]. |
4942 | ** |
4943 | ** As long as the input parameters are correct, these routines will only |
4944 | ** fail if an out-of-memory error occurs during a format conversion. |
4945 | ** Only the following subset of interfaces are subject to out-of-memory |
4946 | ** errors: |
4947 | ** |
4948 | ** <ul> |
4949 | ** <li> sqlite3_column_blob() |
4950 | ** <li> sqlite3_column_text() |
4951 | ** <li> sqlite3_column_text16() |
4952 | ** <li> sqlite3_column_bytes() |
4953 | ** <li> sqlite3_column_bytes16() |
4954 | ** </ul> |
4955 | ** |
4956 | ** If an out-of-memory error occurs, then the return value from these |
4957 | ** routines is the same as if the column had contained an SQL NULL value. |
4958 | ** Valid SQL NULL returns can be distinguished from out-of-memory errors |
4959 | ** by invoking the [sqlite3_errcode()] immediately after the suspect |
4960 | ** return value is obtained and before any |
4961 | ** other SQLite interface is called on the same [database connection]. |
4962 | */ |
4963 | SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); |
4964 | SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol); |
4965 | SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol); |
4966 | SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); |
4967 | SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); |
4968 | SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); |
4969 | SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); |
4970 | SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol); |
4971 | SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); |
4972 | SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol); |
4973 | |
4974 | /* |
4975 | ** CAPI3REF: Destroy A Prepared Statement Object |
4976 | ** DESTRUCTOR: sqlite3_stmt |
4977 | ** |
4978 | ** ^The sqlite3_finalize() function is called to delete a [prepared statement]. |
4979 | ** ^If the most recent evaluation of the statement encountered no errors |
4980 | ** or if the statement is never been evaluated, then sqlite3_finalize() returns |
4981 | ** SQLITE_OK. ^If the most recent evaluation of statement S failed, then |
4982 | ** sqlite3_finalize(S) returns the appropriate [error code] or |
4983 | ** [extended error code]. |
4984 | ** |
4985 | ** ^The sqlite3_finalize(S) routine can be called at any point during |
4986 | ** the life cycle of [prepared statement] S: |
4987 | ** before statement S is ever evaluated, after |
4988 | ** one or more calls to [sqlite3_reset()], or after any call |
4989 | ** to [sqlite3_step()] regardless of whether or not the statement has |
4990 | ** completed execution. |
4991 | ** |
4992 | ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op. |
4993 | ** |
4994 | ** The application must finalize every [prepared statement] in order to avoid |
4995 | ** resource leaks. It is a grievous error for the application to try to use |
4996 | ** a prepared statement after it has been finalized. Any use of a prepared |
4997 | ** statement after it has been finalized can result in undefined and |
4998 | ** undesirable behavior such as segfaults and heap corruption. |
4999 | */ |
5000 | SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt); |
5001 | |
5002 | /* |
5003 | ** CAPI3REF: Reset A Prepared Statement Object |
5004 | ** METHOD: sqlite3_stmt |
5005 | ** |
5006 | ** The sqlite3_reset() function is called to reset a [prepared statement] |
5007 | ** object back to its initial state, ready to be re-executed. |
5008 | ** ^Any SQL statement variables that had values bound to them using |
5009 | ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. |
5010 | ** Use [sqlite3_clear_bindings()] to reset the bindings. |
5011 | ** |
5012 | ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S |
5013 | ** back to the beginning of its program. |
5014 | ** |
5015 | ** ^If the most recent call to [sqlite3_step(S)] for the |
5016 | ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE], |
5017 | ** or if [sqlite3_step(S)] has never before been called on S, |
5018 | ** then [sqlite3_reset(S)] returns [SQLITE_OK]. |
5019 | ** |
5020 | ** ^If the most recent call to [sqlite3_step(S)] for the |
5021 | ** [prepared statement] S indicated an error, then |
5022 | ** [sqlite3_reset(S)] returns an appropriate [error code]. |
5023 | ** |
5024 | ** ^The [sqlite3_reset(S)] interface does not change the values |
5025 | ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. |
5026 | */ |
5027 | SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt); |
5028 | |
5029 | /* |
5030 | ** CAPI3REF: Create Or Redefine SQL Functions |
5031 | ** KEYWORDS: {function creation routines} |
5032 | ** METHOD: sqlite3 |
5033 | ** |
5034 | ** ^These functions (collectively known as "function creation routines") |
5035 | ** are used to add SQL functions or aggregates or to redefine the behavior |
5036 | ** of existing SQL functions or aggregates. The only differences between |
5037 | ** the three "sqlite3_create_function*" routines are the text encoding |
5038 | ** expected for the second parameter (the name of the function being |
5039 | ** created) and the presence or absence of a destructor callback for |
5040 | ** the application data pointer. Function sqlite3_create_window_function() |
5041 | ** is similar, but allows the user to supply the extra callback functions |
5042 | ** needed by [aggregate window functions]. |
5043 | ** |
5044 | ** ^The first parameter is the [database connection] to which the SQL |
5045 | ** function is to be added. ^If an application uses more than one database |
5046 | ** connection then application-defined SQL functions must be added |
5047 | ** to each database connection separately. |
5048 | ** |
5049 | ** ^The second parameter is the name of the SQL function to be created or |
5050 | ** redefined. ^The length of the name is limited to 255 bytes in a UTF-8 |
5051 | ** representation, exclusive of the zero-terminator. ^Note that the name |
5052 | ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. |
5053 | ** ^Any attempt to create a function with a longer name |
5054 | ** will result in [SQLITE_MISUSE] being returned. |
5055 | ** |
5056 | ** ^The third parameter (nArg) |
5057 | ** is the number of arguments that the SQL function or |
5058 | ** aggregate takes. ^If this parameter is -1, then the SQL function or |
5059 | ** aggregate may take any number of arguments between 0 and the limit |
5060 | ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third |
5061 | ** parameter is less than -1 or greater than 127 then the behavior is |
5062 | ** undefined. |
5063 | ** |
5064 | ** ^The fourth parameter, eTextRep, specifies what |
5065 | ** [SQLITE_UTF8 | text encoding] this SQL function prefers for |
5066 | ** its parameters. The application should set this parameter to |
5067 | ** [SQLITE_UTF16LE] if the function implementation invokes |
5068 | ** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the |
5069 | ** implementation invokes [sqlite3_value_text16be()] on an input, or |
5070 | ** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8] |
5071 | ** otherwise. ^The same SQL function may be registered multiple times using |
5072 | ** different preferred text encodings, with different implementations for |
5073 | ** each encoding. |
5074 | ** ^When multiple implementations of the same function are available, SQLite |
5075 | ** will pick the one that involves the least amount of data conversion. |
5076 | ** |
5077 | ** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC] |
5078 | ** to signal that the function will always return the same result given |
5079 | ** the same inputs within a single SQL statement. Most SQL functions are |
5080 | ** deterministic. The built-in [random()] SQL function is an example of a |
5081 | ** function that is not deterministic. The SQLite query planner is able to |
5082 | ** perform additional optimizations on deterministic functions, so use |
5083 | ** of the [SQLITE_DETERMINISTIC] flag is recommended where possible. |
5084 | ** |
5085 | ** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY] |
5086 | ** flag, which if present prevents the function from being invoked from |
5087 | ** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions, |
5088 | ** index expressions, or the WHERE clause of partial indexes. |
5089 | ** |
5090 | ** <span style="background-color:#ffff90;"> |
5091 | ** For best security, the [SQLITE_DIRECTONLY] flag is recommended for |
5092 | ** all application-defined SQL functions that do not need to be |
5093 | ** used inside of triggers, view, CHECK constraints, or other elements of |
5094 | ** the database schema. This flags is especially recommended for SQL |
5095 | ** functions that have side effects or reveal internal application state. |
5096 | ** Without this flag, an attacker might be able to modify the schema of |
5097 | ** a database file to include invocations of the function with parameters |
5098 | ** chosen by the attacker, which the application will then execute when |
5099 | ** the database file is opened and read. |
5100 | ** </span> |
5101 | ** |
5102 | ** ^(The fifth parameter is an arbitrary pointer. The implementation of the |
5103 | ** function can gain access to this pointer using [sqlite3_user_data()].)^ |
5104 | ** |
5105 | ** ^The sixth, seventh and eighth parameters passed to the three |
5106 | ** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are |
5107 | ** pointers to C-language functions that implement the SQL function or |
5108 | ** aggregate. ^A scalar SQL function requires an implementation of the xFunc |
5109 | ** callback only; NULL pointers must be passed as the xStep and xFinal |
5110 | ** parameters. ^An aggregate SQL function requires an implementation of xStep |
5111 | ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing |
5112 | ** SQL function or aggregate, pass NULL pointers for all three function |
5113 | ** callbacks. |
5114 | ** |
5115 | ** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue |
5116 | ** and xInverse) passed to sqlite3_create_window_function are pointers to |
5117 | ** C-language callbacks that implement the new function. xStep and xFinal |
5118 | ** must both be non-NULL. xValue and xInverse may either both be NULL, in |
5119 | ** which case a regular aggregate function is created, or must both be |
5120 | ** non-NULL, in which case the new function may be used as either an aggregate |
5121 | ** or aggregate window function. More details regarding the implementation |
5122 | ** of aggregate window functions are |
5123 | ** [user-defined window functions|available here]. |
5124 | ** |
5125 | ** ^(If the final parameter to sqlite3_create_function_v2() or |
5126 | ** sqlite3_create_window_function() is not NULL, then it is destructor for |
5127 | ** the application data pointer. The destructor is invoked when the function |
5128 | ** is deleted, either by being overloaded or when the database connection |
5129 | ** closes.)^ ^The destructor is also invoked if the call to |
5130 | ** sqlite3_create_function_v2() fails. ^When the destructor callback is |
5131 | ** invoked, it is passed a single argument which is a copy of the application |
5132 | ** data pointer which was the fifth parameter to sqlite3_create_function_v2(). |
5133 | ** |
5134 | ** ^It is permitted to register multiple implementations of the same |
5135 | ** functions with the same name but with either differing numbers of |
5136 | ** arguments or differing preferred text encodings. ^SQLite will use |
5137 | ** the implementation that most closely matches the way in which the |
5138 | ** SQL function is used. ^A function implementation with a non-negative |
5139 | ** nArg parameter is a better match than a function implementation with |
5140 | ** a negative nArg. ^A function where the preferred text encoding |
5141 | ** matches the database encoding is a better |
5142 | ** match than a function where the encoding is different. |
5143 | ** ^A function where the encoding difference is between UTF16le and UTF16be |
5144 | ** is a closer match than a function where the encoding difference is |
5145 | ** between UTF8 and UTF16. |
5146 | ** |
5147 | ** ^Built-in functions may be overloaded by new application-defined functions. |
5148 | ** |
5149 | ** ^An application-defined function is permitted to call other |
5150 | ** SQLite interfaces. However, such calls must not |
5151 | ** close the database connection nor finalize or reset the prepared |
5152 | ** statement in which the function is running. |
5153 | */ |
5154 | SQLITE_API int sqlite3_create_function( |
5155 | sqlite3 *db, |
5156 | const char *zFunctionName, |
5157 | int nArg, |
5158 | int eTextRep, |
5159 | void *pApp, |
5160 | void (*xFunc)(sqlite3_context*,int,sqlite3_value**), |
5161 | void (*xStep)(sqlite3_context*,int,sqlite3_value**), |
5162 | void (*xFinal)(sqlite3_context*) |
5163 | ); |
5164 | SQLITE_API int sqlite3_create_function16( |
5165 | sqlite3 *db, |
5166 | const void *zFunctionName, |
5167 | int nArg, |
5168 | int eTextRep, |
5169 | void *pApp, |
5170 | void (*xFunc)(sqlite3_context*,int,sqlite3_value**), |
5171 | void (*xStep)(sqlite3_context*,int,sqlite3_value**), |
5172 | void (*xFinal)(sqlite3_context*) |
5173 | ); |
5174 | SQLITE_API int sqlite3_create_function_v2( |
5175 | sqlite3 *db, |
5176 | const char *zFunctionName, |
5177 | int nArg, |
5178 | int eTextRep, |
5179 | void *pApp, |
5180 | void (*xFunc)(sqlite3_context*,int,sqlite3_value**), |
5181 | void (*xStep)(sqlite3_context*,int,sqlite3_value**), |
5182 | void (*xFinal)(sqlite3_context*), |
5183 | void(*xDestroy)(void*) |
5184 | ); |
5185 | SQLITE_API int sqlite3_create_window_function( |
5186 | sqlite3 *db, |
5187 | const char *zFunctionName, |
5188 | int nArg, |
5189 | int eTextRep, |
5190 | void *pApp, |
5191 | void (*xStep)(sqlite3_context*,int,sqlite3_value**), |
5192 | void (*xFinal)(sqlite3_context*), |
5193 | void (*xValue)(sqlite3_context*), |
5194 | void (*xInverse)(sqlite3_context*,int,sqlite3_value**), |
5195 | void(*xDestroy)(void*) |
5196 | ); |
5197 | |
5198 | /* |
5199 | ** CAPI3REF: Text Encodings |
5200 | ** |
5201 | ** These constant define integer codes that represent the various |
5202 | ** text encodings supported by SQLite. |
5203 | */ |
5204 | #define SQLITE_UTF8 1 /* IMP: R-37514-35566 */ |
5205 | #define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */ |
5206 | #define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */ |
5207 | #define SQLITE_UTF16 4 /* Use native byte order */ |
5208 | #define SQLITE_ANY 5 /* Deprecated */ |
5209 | #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ |
5210 | |
5211 | /* |
5212 | ** CAPI3REF: Function Flags |
5213 | ** |
5214 | ** These constants may be ORed together with the |
5215 | ** [SQLITE_UTF8 | preferred text encoding] as the fourth argument |
5216 | ** to [sqlite3_create_function()], [sqlite3_create_function16()], or |
5217 | ** [sqlite3_create_function_v2()]. |
5218 | ** |
5219 | ** <dl> |
5220 | ** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd> |
5221 | ** The SQLITE_DETERMINISTIC flag means that the new function always gives |
5222 | ** the same output when the input parameters are the same. |
5223 | ** The [abs|abs() function] is deterministic, for example, but |
5224 | ** [randomblob|randomblob()] is not. Functions must |
5225 | ** be deterministic in order to be used in certain contexts such as |
5226 | ** with the WHERE clause of [partial indexes] or in [generated columns]. |
5227 | ** SQLite might also optimize deterministic functions by factoring them |
5228 | ** out of inner loops. |
5229 | ** </dd> |
5230 | ** |
5231 | ** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd> |
5232 | ** The SQLITE_DIRECTONLY flag means that the function may only be invoked |
5233 | ** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in |
5234 | ** schema structures such as [CHECK constraints], [DEFAULT clauses], |
5235 | ** [expression indexes], [partial indexes], or [generated columns]. |
5236 | ** The SQLITE_DIRECTONLY flags is a security feature which is recommended |
5237 | ** for all [application-defined SQL functions], and especially for functions |
5238 | ** that have side-effects or that could potentially leak sensitive |
5239 | ** information. |
5240 | ** </dd> |
5241 | ** |
5242 | ** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd> |
5243 | ** The SQLITE_INNOCUOUS flag means that the function is unlikely |
5244 | ** to cause problems even if misused. An innocuous function should have |
5245 | ** no side effects and should not depend on any values other than its |
5246 | ** input parameters. The [abs|abs() function] is an example of an |
5247 | ** innocuous function. |
5248 | ** The [load_extension() SQL function] is not innocuous because of its |
5249 | ** side effects. |
5250 | ** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not |
5251 | ** exactly the same. The [random|random() function] is an example of a |
5252 | ** function that is innocuous but not deterministic. |
5253 | ** <p>Some heightened security settings |
5254 | ** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF]) |
5255 | ** disable the use of SQL functions inside views and triggers and in |
5256 | ** schema structures such as [CHECK constraints], [DEFAULT clauses], |
5257 | ** [expression indexes], [partial indexes], and [generated columns] unless |
5258 | ** the function is tagged with SQLITE_INNOCUOUS. Most built-in functions |
5259 | ** are innocuous. Developers are advised to avoid using the |
5260 | ** SQLITE_INNOCUOUS flag for application-defined functions unless the |
5261 | ** function has been carefully audited and found to be free of potentially |
5262 | ** security-adverse side-effects and information-leaks. |
5263 | ** </dd> |
5264 | ** |
5265 | ** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd> |
5266 | ** The SQLITE_SUBTYPE flag indicates to SQLite that a function may call |
5267 | ** [sqlite3_value_subtype()] to inspect the sub-types of its arguments. |
5268 | ** Specifying this flag makes no difference for scalar or aggregate user |
5269 | ** functions. However, if it is not specified for a user-defined window |
5270 | ** function, then any sub-types belonging to arguments passed to the window |
5271 | ** function may be discarded before the window function is called (i.e. |
5272 | ** sqlite3_value_subtype() will always return 0). |
5273 | ** </dd> |
5274 | ** </dl> |
5275 | */ |
5276 | #define SQLITE_DETERMINISTIC 0x000000800 |
5277 | #define SQLITE_DIRECTONLY 0x000080000 |
5278 | #define SQLITE_SUBTYPE 0x000100000 |
5279 | #define SQLITE_INNOCUOUS 0x000200000 |
5280 | |
5281 | /* |
5282 | ** CAPI3REF: Deprecated Functions |
5283 | ** DEPRECATED |
5284 | ** |
5285 | ** These functions are [deprecated]. In order to maintain |
5286 | ** backwards compatibility with older code, these functions continue |
5287 | ** to be supported. However, new applications should avoid |
5288 | ** the use of these functions. To encourage programmers to avoid |
5289 | ** these functions, we will not explain what they do. |
5290 | */ |
5291 | #ifndef SQLITE_OMIT_DEPRECATED |
5292 | SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); |
5293 | SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); |
5294 | SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); |
5295 | SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void); |
5296 | SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); |
5297 | SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int), |
5298 | void*,sqlite3_int64); |
5299 | #endif |
5300 | |
5301 | /* |
5302 | ** CAPI3REF: Obtaining SQL Values |
5303 | ** METHOD: sqlite3_value |
5304 | ** |
5305 | ** <b>Summary:</b> |
5306 | ** <blockquote><table border=0 cellpadding=0 cellspacing=0> |
5307 | ** <tr><td><b>sqlite3_value_blob</b><td>→<td>BLOB value |
5308 | ** <tr><td><b>sqlite3_value_double</b><td>→<td>REAL value |
5309 | ** <tr><td><b>sqlite3_value_int</b><td>→<td>32-bit INTEGER value |
5310 | ** <tr><td><b>sqlite3_value_int64</b><td>→<td>64-bit INTEGER value |
5311 | ** <tr><td><b>sqlite3_value_pointer</b><td>→<td>Pointer value |
5312 | ** <tr><td><b>sqlite3_value_text</b><td>→<td>UTF-8 TEXT value |
5313 | ** <tr><td><b>sqlite3_value_text16</b><td>→<td>UTF-16 TEXT value in |
5314 | ** the native byteorder |
5315 | ** <tr><td><b>sqlite3_value_text16be</b><td>→<td>UTF-16be TEXT value |
5316 | ** <tr><td><b>sqlite3_value_text16le</b><td>→<td>UTF-16le TEXT value |
5317 | ** <tr><td> <td> <td> |
5318 | ** <tr><td><b>sqlite3_value_bytes</b><td>→<td>Size of a BLOB |
5319 | ** or a UTF-8 TEXT in bytes |
5320 | ** <tr><td><b>sqlite3_value_bytes16 </b> |
5321 | ** <td>→ <td>Size of UTF-16 |
5322 | ** TEXT in bytes |
5323 | ** <tr><td><b>sqlite3_value_type</b><td>→<td>Default |
5324 | ** datatype of the value |
5325 | ** <tr><td><b>sqlite3_value_numeric_type </b> |
5326 | ** <td>→ <td>Best numeric datatype of the value |
5327 | ** <tr><td><b>sqlite3_value_nochange </b> |
5328 | ** <td>→ <td>True if the column is unchanged in an UPDATE |
5329 | ** against a virtual table. |
5330 | ** <tr><td><b>sqlite3_value_frombind </b> |
5331 | ** <td>→ <td>True if value originated from a [bound parameter] |
5332 | ** </table></blockquote> |
5333 | ** |
5334 | ** <b>Details:</b> |
5335 | ** |
5336 | ** These routines extract type, size, and content information from |
5337 | ** [protected sqlite3_value] objects. Protected sqlite3_value objects |
5338 | ** are used to pass parameter information into the functions that |
5339 | ** implement [application-defined SQL functions] and [virtual tables]. |
5340 | ** |
5341 | ** These routines work only with [protected sqlite3_value] objects. |
5342 | ** Any attempt to use these routines on an [unprotected sqlite3_value] |
5343 | ** is not threadsafe. |
5344 | ** |
5345 | ** ^These routines work just like the corresponding [column access functions] |
5346 | ** except that these routines take a single [protected sqlite3_value] object |
5347 | ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. |
5348 | ** |
5349 | ** ^The sqlite3_value_text16() interface extracts a UTF-16 string |
5350 | ** in the native byte-order of the host machine. ^The |
5351 | ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces |
5352 | ** extract UTF-16 strings as big-endian and little-endian respectively. |
5353 | ** |
5354 | ** ^If [sqlite3_value] object V was initialized |
5355 | ** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)] |
5356 | ** and if X and Y are strings that compare equal according to strcmp(X,Y), |
5357 | ** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise, |
5358 | ** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer() |
5359 | ** routine is part of the [pointer passing interface] added for SQLite 3.20.0. |
5360 | ** |
5361 | ** ^(The sqlite3_value_type(V) interface returns the |
5362 | ** [SQLITE_INTEGER | datatype code] for the initial datatype of the |
5363 | ** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER], |
5364 | ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^ |
5365 | ** Other interfaces might change the datatype for an sqlite3_value object. |
5366 | ** For example, if the datatype is initially SQLITE_INTEGER and |
5367 | ** sqlite3_value_text(V) is called to extract a text value for that |
5368 | ** integer, then subsequent calls to sqlite3_value_type(V) might return |
5369 | ** SQLITE_TEXT. Whether or not a persistent internal datatype conversion |
5370 | ** occurs is undefined and may change from one release of SQLite to the next. |
5371 | ** |
5372 | ** ^(The sqlite3_value_numeric_type() interface attempts to apply |
5373 | ** numeric affinity to the value. This means that an attempt is |
5374 | ** made to convert the value to an integer or floating point. If |
5375 | ** such a conversion is possible without loss of information (in other |
5376 | ** words, if the value is a string that looks like a number) |
5377 | ** then the conversion is performed. Otherwise no conversion occurs. |
5378 | ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^ |
5379 | ** |
5380 | ** ^Within the [xUpdate] method of a [virtual table], the |
5381 | ** sqlite3_value_nochange(X) interface returns true if and only if |
5382 | ** the column corresponding to X is unchanged by the UPDATE operation |
5383 | ** that the xUpdate method call was invoked to implement and if |
5384 | ** and the prior [xColumn] method call that was invoked to extracted |
5385 | ** the value for that column returned without setting a result (probably |
5386 | ** because it queried [sqlite3_vtab_nochange()] and found that the column |
5387 | ** was unchanging). ^Within an [xUpdate] method, any value for which |
5388 | ** sqlite3_value_nochange(X) is true will in all other respects appear |
5389 | ** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other |
5390 | ** than within an [xUpdate] method call for an UPDATE statement, then |
5391 | ** the return value is arbitrary and meaningless. |
5392 | ** |
5393 | ** ^The sqlite3_value_frombind(X) interface returns non-zero if the |
5394 | ** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()] |
5395 | ** interfaces. ^If X comes from an SQL literal value, or a table column, |
5396 | ** or an expression, then sqlite3_value_frombind(X) returns zero. |
5397 | ** |
5398 | ** Please pay particular attention to the fact that the pointer returned |
5399 | ** from [sqlite3_value_blob()], [sqlite3_value_text()], or |
5400 | ** [sqlite3_value_text16()] can be invalidated by a subsequent call to |
5401 | ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], |
5402 | ** or [sqlite3_value_text16()]. |
5403 | ** |
5404 | ** These routines must be called from the same thread as |
5405 | ** the SQL function that supplied the [sqlite3_value*] parameters. |
5406 | ** |
5407 | ** As long as the input parameter is correct, these routines can only |
5408 | ** fail if an out-of-memory error occurs during a format conversion. |
5409 | ** Only the following subset of interfaces are subject to out-of-memory |
5410 | ** errors: |
5411 | ** |
5412 | ** <ul> |
5413 | ** <li> sqlite3_value_blob() |
5414 | ** <li> sqlite3_value_text() |
5415 | ** <li> sqlite3_value_text16() |
5416 | ** <li> sqlite3_value_text16le() |
5417 | ** <li> sqlite3_value_text16be() |
5418 | ** <li> sqlite3_value_bytes() |
5419 | ** <li> sqlite3_value_bytes16() |
5420 | ** </ul> |
5421 | ** |
5422 | ** If an out-of-memory error occurs, then the return value from these |
5423 | ** routines is the same as if the column had contained an SQL NULL value. |
5424 | ** Valid SQL NULL returns can be distinguished from out-of-memory errors |
5425 | ** by invoking the [sqlite3_errcode()] immediately after the suspect |
5426 | ** return value is obtained and before any |
5427 | ** other SQLite interface is called on the same [database connection]. |
5428 | */ |
5429 | SQLITE_API const void *sqlite3_value_blob(sqlite3_value*); |
5430 | SQLITE_API double sqlite3_value_double(sqlite3_value*); |
5431 | SQLITE_API int sqlite3_value_int(sqlite3_value*); |
5432 | SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*); |
5433 | SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*); |
5434 | SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*); |
5435 | SQLITE_API const void *sqlite3_value_text16(sqlite3_value*); |
5436 | SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*); |
5437 | SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*); |
5438 | SQLITE_API int sqlite3_value_bytes(sqlite3_value*); |
5439 | SQLITE_API int sqlite3_value_bytes16(sqlite3_value*); |
5440 | SQLITE_API int sqlite3_value_type(sqlite3_value*); |
5441 | SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*); |
5442 | SQLITE_API int sqlite3_value_nochange(sqlite3_value*); |
5443 | SQLITE_API int sqlite3_value_frombind(sqlite3_value*); |
5444 | |
5445 | /* |
5446 | ** CAPI3REF: Finding The Subtype Of SQL Values |
5447 | ** METHOD: sqlite3_value |
5448 | ** |
5449 | ** The sqlite3_value_subtype(V) function returns the subtype for |
5450 | ** an [application-defined SQL function] argument V. The subtype |
5451 | ** information can be used to pass a limited amount of context from |
5452 | ** one SQL function to another. Use the [sqlite3_result_subtype()] |
5453 | ** routine to set the subtype for the return value of an SQL function. |
5454 | */ |
5455 | SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*); |
5456 | |
5457 | /* |
5458 | ** CAPI3REF: Copy And Free SQL Values |
5459 | ** METHOD: sqlite3_value |
5460 | ** |
5461 | ** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value] |
5462 | ** object D and returns a pointer to that copy. ^The [sqlite3_value] returned |
5463 | ** is a [protected sqlite3_value] object even if the input is not. |
5464 | ** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a |
5465 | ** memory allocation fails. |
5466 | ** |
5467 | ** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object |
5468 | ** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer |
5469 | ** then sqlite3_value_free(V) is a harmless no-op. |
5470 | */ |
5471 | SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*); |
5472 | SQLITE_API void sqlite3_value_free(sqlite3_value*); |
5473 | |
5474 | /* |
5475 | ** CAPI3REF: Obtain Aggregate Function Context |
5476 | ** METHOD: sqlite3_context |
5477 | ** |
5478 | ** Implementations of aggregate SQL functions use this |
5479 | ** routine to allocate memory for storing their state. |
5480 | ** |
5481 | ** ^The first time the sqlite3_aggregate_context(C,N) routine is called |
5482 | ** for a particular aggregate function, SQLite allocates |
5483 | ** N bytes of memory, zeroes out that memory, and returns a pointer |
5484 | ** to the new memory. ^On second and subsequent calls to |
5485 | ** sqlite3_aggregate_context() for the same aggregate function instance, |
5486 | ** the same buffer is returned. Sqlite3_aggregate_context() is normally |
5487 | ** called once for each invocation of the xStep callback and then one |
5488 | ** last time when the xFinal callback is invoked. ^(When no rows match |
5489 | ** an aggregate query, the xStep() callback of the aggregate function |
5490 | ** implementation is never called and xFinal() is called exactly once. |
5491 | ** In those cases, sqlite3_aggregate_context() might be called for the |
5492 | ** first time from within xFinal().)^ |
5493 | ** |
5494 | ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer |
5495 | ** when first called if N is less than or equal to zero or if a memory |
5496 | ** allocate error occurs. |
5497 | ** |
5498 | ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is |
5499 | ** determined by the N parameter on first successful call. Changing the |
5500 | ** value of N in any subsequent call to sqlite3_aggregate_context() within |
5501 | ** the same aggregate function instance will not resize the memory |
5502 | ** allocation.)^ Within the xFinal callback, it is customary to set |
5503 | ** N=0 in calls to sqlite3_aggregate_context(C,N) so that no |
5504 | ** pointless memory allocations occur. |
5505 | ** |
5506 | ** ^SQLite automatically frees the memory allocated by |
5507 | ** sqlite3_aggregate_context() when the aggregate query concludes. |
5508 | ** |
5509 | ** The first parameter must be a copy of the |
5510 | ** [sqlite3_context | SQL function context] that is the first parameter |
5511 | ** to the xStep or xFinal callback routine that implements the aggregate |
5512 | ** function. |
5513 | ** |
5514 | ** This routine must be called from the same thread in which |
5515 | ** the aggregate SQL function is running. |
5516 | */ |
5517 | SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); |
5518 | |
5519 | /* |
5520 | ** CAPI3REF: User Data For Functions |
5521 | ** METHOD: sqlite3_context |
5522 | ** |
5523 | ** ^The sqlite3_user_data() interface returns a copy of |
5524 | ** the pointer that was the pUserData parameter (the 5th parameter) |
5525 | ** of the [sqlite3_create_function()] |
5526 | ** and [sqlite3_create_function16()] routines that originally |
5527 | ** registered the application defined function. |
5528 | ** |
5529 | ** This routine must be called from the same thread in which |
5530 | ** the application-defined function is running. |
5531 | */ |
5532 | SQLITE_API void *sqlite3_user_data(sqlite3_context*); |
5533 | |
5534 | /* |
5535 | ** CAPI3REF: Database Connection For Functions |
5536 | ** METHOD: sqlite3_context |
5537 | ** |
5538 | ** ^The sqlite3_context_db_handle() interface returns a copy of |
5539 | ** the pointer to the [database connection] (the 1st parameter) |
5540 | ** of the [sqlite3_create_function()] |
5541 | ** and [sqlite3_create_function16()] routines that originally |
5542 | ** registered the application defined function. |
5543 | */ |
5544 | SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*); |
5545 | |
5546 | /* |
5547 | ** CAPI3REF: Function Auxiliary Data |
5548 | ** METHOD: sqlite3_context |
5549 | ** |
5550 | ** These functions may be used by (non-aggregate) SQL functions to |
5551 | ** associate metadata with argument values. If the same value is passed to |
5552 | ** multiple invocations of the same SQL function during query execution, under |
5553 | ** some circumstances the associated metadata may be preserved. An example |
5554 | ** of where this might be useful is in a regular-expression matching |
5555 | ** function. The compiled version of the regular expression can be stored as |
5556 | ** metadata associated with the pattern string. |
5557 | ** Then as long as the pattern string remains the same, |
5558 | ** the compiled regular expression can be reused on multiple |
5559 | ** invocations of the same function. |
5560 | ** |
5561 | ** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata |
5562 | ** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument |
5563 | ** value to the application-defined function. ^N is zero for the left-most |
5564 | ** function argument. ^If there is no metadata |
5565 | ** associated with the function argument, the sqlite3_get_auxdata(C,N) interface |
5566 | ** returns a NULL pointer. |
5567 | ** |
5568 | ** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th |
5569 | ** argument of the application-defined function. ^Subsequent |
5570 | ** calls to sqlite3_get_auxdata(C,N) return P from the most recent |
5571 | ** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or |
5572 | ** NULL if the metadata has been discarded. |
5573 | ** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL, |
5574 | ** SQLite will invoke the destructor function X with parameter P exactly |
5575 | ** once, when the metadata is discarded. |
5576 | ** SQLite is free to discard the metadata at any time, including: <ul> |
5577 | ** <li> ^(when the corresponding function parameter changes)^, or |
5578 | ** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the |
5579 | ** SQL statement)^, or |
5580 | ** <li> ^(when sqlite3_set_auxdata() is invoked again on the same |
5581 | ** parameter)^, or |
5582 | ** <li> ^(during the original sqlite3_set_auxdata() call when a memory |
5583 | ** allocation error occurs.)^ </ul> |
5584 | ** |
5585 | ** Note the last bullet in particular. The destructor X in |
5586 | ** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the |
5587 | ** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata() |
5588 | ** should be called near the end of the function implementation and the |
5589 | ** function implementation should not make any use of P after |
5590 | ** sqlite3_set_auxdata() has been called. |
5591 | ** |
5592 | ** ^(In practice, metadata is preserved between function calls for |
5593 | ** function parameters that are compile-time constants, including literal |
5594 | ** values and [parameters] and expressions composed from the same.)^ |
5595 | ** |
5596 | ** The value of the N parameter to these interfaces should be non-negative. |
5597 | ** Future enhancements may make use of negative N values to define new |
5598 | ** kinds of function caching behavior. |
5599 | ** |
5600 | ** These routines must be called from the same thread in which |
5601 | ** the SQL function is running. |
5602 | */ |
5603 | SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N); |
5604 | SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); |
5605 | |
5606 | |
5607 | /* |
5608 | ** CAPI3REF: Constants Defining Special Destructor Behavior |
5609 | ** |
5610 | ** These are special values for the destructor that is passed in as the |
5611 | ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor |
5612 | ** argument is SQLITE_STATIC, it means that the content pointer is constant |
5613 | ** and will never change. It does not need to be destroyed. ^The |
5614 | ** SQLITE_TRANSIENT value means that the content will likely change in |
5615 | ** the near future and that SQLite should make its own private copy of |
5616 | ** the content before returning. |
5617 | ** |
5618 | ** The typedef is necessary to work around problems in certain |
5619 | ** C++ compilers. |
5620 | */ |
5621 | typedef void (*sqlite3_destructor_type)(void*); |
5622 | #define SQLITE_STATIC ((sqlite3_destructor_type)0) |
5623 | #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) |
5624 | |
5625 | /* |
5626 | ** CAPI3REF: Setting The Result Of An SQL Function |
5627 | ** METHOD: sqlite3_context |
5628 | ** |
5629 | ** These routines are used by the xFunc or xFinal callbacks that |
5630 | ** implement SQL functions and aggregates. See |
5631 | ** [sqlite3_create_function()] and [sqlite3_create_function16()] |
5632 | ** for additional information. |
5633 | ** |
5634 | ** These functions work very much like the [parameter binding] family of |
5635 | ** functions used to bind values to host parameters in prepared statements. |
5636 | ** Refer to the [SQL parameter] documentation for additional information. |
5637 | ** |
5638 | ** ^The sqlite3_result_blob() interface sets the result from |
5639 | ** an application-defined function to be the BLOB whose content is pointed |
5640 | ** to by the second parameter and which is N bytes long where N is the |
5641 | ** third parameter. |
5642 | ** |
5643 | ** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N) |
5644 | ** interfaces set the result of the application-defined function to be |
5645 | ** a BLOB containing all zero bytes and N bytes in size. |
5646 | ** |
5647 | ** ^The sqlite3_result_double() interface sets the result from |
5648 | ** an application-defined function to be a floating point value specified |
5649 | ** by its 2nd argument. |
5650 | ** |
5651 | ** ^The sqlite3_result_error() and sqlite3_result_error16() functions |
5652 | ** cause the implemented SQL function to throw an exception. |
5653 | ** ^SQLite uses the string pointed to by the |
5654 | ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() |
5655 | ** as the text of an error message. ^SQLite interprets the error |
5656 | ** message string from sqlite3_result_error() as UTF-8. ^SQLite |
5657 | ** interprets the string from sqlite3_result_error16() as UTF-16 using |
5658 | ** the same [byte-order determination rules] as [sqlite3_bind_text16()]. |
5659 | ** ^If the third parameter to sqlite3_result_error() |
5660 | ** or sqlite3_result_error16() is negative then SQLite takes as the error |
5661 | ** message all text up through the first zero character. |
5662 | ** ^If the third parameter to sqlite3_result_error() or |
5663 | ** sqlite3_result_error16() is non-negative then SQLite takes that many |
5664 | ** bytes (not characters) from the 2nd parameter as the error message. |
5665 | ** ^The sqlite3_result_error() and sqlite3_result_error16() |
5666 | ** routines make a private copy of the error message text before |
5667 | ** they return. Hence, the calling function can deallocate or |
5668 | ** modify the text after they return without harm. |
5669 | ** ^The sqlite3_result_error_code() function changes the error code |
5670 | ** returned by SQLite as a result of an error in a function. ^By default, |
5671 | ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error() |
5672 | ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. |
5673 | ** |
5674 | ** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an |
5675 | ** error indicating that a string or BLOB is too long to represent. |
5676 | ** |
5677 | ** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an |
5678 | ** error indicating that a memory allocation failed. |
5679 | ** |
5680 | ** ^The sqlite3_result_int() interface sets the return value |
5681 | ** of the application-defined function to be the 32-bit signed integer |
5682 | ** value given in the 2nd argument. |
5683 | ** ^The sqlite3_result_int64() interface sets the return value |
5684 | ** of the application-defined function to be the 64-bit signed integer |
5685 | ** value given in the 2nd argument. |
5686 | ** |
5687 | ** ^The sqlite3_result_null() interface sets the return value |
5688 | ** of the application-defined function to be NULL. |
5689 | ** |
5690 | ** ^The sqlite3_result_text(), sqlite3_result_text16(), |
5691 | ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces |
5692 | ** set the return value of the application-defined function to be |
5693 | ** a text string which is represented as UTF-8, UTF-16 native byte order, |
5694 | ** UTF-16 little endian, or UTF-16 big endian, respectively. |
5695 | ** ^The sqlite3_result_text64() interface sets the return value of an |
5696 | ** application-defined function to be a text string in an encoding |
5697 | ** specified by the fifth (and last) parameter, which must be one |
5698 | ** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]. |
5699 | ** ^SQLite takes the text result from the application from |
5700 | ** the 2nd parameter of the sqlite3_result_text* interfaces. |
5701 | ** ^If the 3rd parameter to the sqlite3_result_text* interfaces |
5702 | ** is negative, then SQLite takes result text from the 2nd parameter |
5703 | ** through the first zero character. |
5704 | ** ^If the 3rd parameter to the sqlite3_result_text* interfaces |
5705 | ** is non-negative, then as many bytes (not characters) of the text |
5706 | ** pointed to by the 2nd parameter are taken as the application-defined |
5707 | ** function result. If the 3rd parameter is non-negative, then it |
5708 | ** must be the byte offset into the string where the NUL terminator would |
5709 | ** appear if the string where NUL terminated. If any NUL characters occur |
5710 | ** in the string at a byte offset that is less than the value of the 3rd |
5711 | ** parameter, then the resulting string will contain embedded NULs and the |
5712 | ** result of expressions operating on strings with embedded NULs is undefined. |
5713 | ** ^If the 4th parameter to the sqlite3_result_text* interfaces |
5714 | ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that |
5715 | ** function as the destructor on the text or BLOB result when it has |
5716 | ** finished using that result. |
5717 | ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to |
5718 | ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite |
5719 | ** assumes that the text or BLOB result is in constant space and does not |
5720 | ** copy the content of the parameter nor call a destructor on the content |
5721 | ** when it has finished using that result. |
5722 | ** ^If the 4th parameter to the sqlite3_result_text* interfaces |
5723 | ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT |
5724 | ** then SQLite makes a copy of the result into space obtained |
5725 | ** from [sqlite3_malloc()] before it returns. |
5726 | ** |
5727 | ** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and |
5728 | ** sqlite3_result_text16be() routines, and for sqlite3_result_text64() |
5729 | ** when the encoding is not UTF8, if the input UTF16 begins with a |
5730 | ** byte-order mark (BOM, U+FEFF) then the BOM is removed from the |
5731 | ** string and the rest of the string is interpreted according to the |
5732 | ** byte-order specified by the BOM. ^The byte-order specified by |
5733 | ** the BOM at the beginning of the text overrides the byte-order |
5734 | ** specified by the interface procedure. ^So, for example, if |
5735 | ** sqlite3_result_text16le() is invoked with text that begins |
5736 | ** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the |
5737 | ** first two bytes of input are skipped and the remaining input |
5738 | ** is interpreted as UTF16BE text. |
5739 | ** |
5740 | ** ^For UTF16 input text to the sqlite3_result_text16(), |
5741 | ** sqlite3_result_text16be(), sqlite3_result_text16le(), and |
5742 | ** sqlite3_result_text64() routines, if the text contains invalid |
5743 | ** UTF16 characters, the invalid characters might be converted |
5744 | ** into the unicode replacement character, U+FFFD. |
5745 | ** |
5746 | ** ^The sqlite3_result_value() interface sets the result of |
5747 | ** the application-defined function to be a copy of the |
5748 | ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The |
5749 | ** sqlite3_result_value() interface makes a copy of the [sqlite3_value] |
5750 | ** so that the [sqlite3_value] specified in the parameter may change or |
5751 | ** be deallocated after sqlite3_result_value() returns without harm. |
5752 | ** ^A [protected sqlite3_value] object may always be used where an |
5753 | ** [unprotected sqlite3_value] object is required, so either |
5754 | ** kind of [sqlite3_value] object can be used with this interface. |
5755 | ** |
5756 | ** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an |
5757 | ** SQL NULL value, just like [sqlite3_result_null(C)], except that it |
5758 | ** also associates the host-language pointer P or type T with that |
5759 | ** NULL value such that the pointer can be retrieved within an |
5760 | ** [application-defined SQL function] using [sqlite3_value_pointer()]. |
5761 | ** ^If the D parameter is not NULL, then it is a pointer to a destructor |
5762 | ** for the P parameter. ^SQLite invokes D with P as its only argument |
5763 | ** when SQLite is finished with P. The T parameter should be a static |
5764 | ** string and preferably a string literal. The sqlite3_result_pointer() |
5765 | ** routine is part of the [pointer passing interface] added for SQLite 3.20.0. |
5766 | ** |
5767 | ** If these routines are called from within the different thread |
5768 | ** than the one containing the application-defined function that received |
5769 | ** the [sqlite3_context] pointer, the results are undefined. |
5770 | */ |
5771 | SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); |
5772 | SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*, |
5773 | sqlite3_uint64,void(*)(void*)); |
5774 | SQLITE_API void sqlite3_result_double(sqlite3_context*, double); |
5775 | SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int); |
5776 | SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int); |
5777 | SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*); |
5778 | SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*); |
5779 | SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int); |
5780 | SQLITE_API void sqlite3_result_int(sqlite3_context*, int); |
5781 | SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); |
5782 | SQLITE_API void sqlite3_result_null(sqlite3_context*); |
5783 | SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); |
5784 | SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64, |
5785 | void(*)(void*), unsigned char encoding); |
5786 | SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); |
5787 | SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); |
5788 | SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); |
5789 | SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*); |
5790 | SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*)); |
5791 | SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n); |
5792 | SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n); |
5793 | |
5794 | |
5795 | /* |
5796 | ** CAPI3REF: Setting The Subtype Of An SQL Function |
5797 | ** METHOD: sqlite3_context |
5798 | ** |
5799 | ** The sqlite3_result_subtype(C,T) function causes the subtype of |
5800 | ** the result from the [application-defined SQL function] with |
5801 | ** [sqlite3_context] C to be the value T. Only the lower 8 bits |
5802 | ** of the subtype T are preserved in current versions of SQLite; |
5803 | ** higher order bits are discarded. |
5804 | ** The number of subtype bytes preserved by SQLite might increase |
5805 | ** in future releases of SQLite. |
5806 | */ |
5807 | SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int); |
5808 | |
5809 | /* |
5810 | ** CAPI3REF: Define New Collating Sequences |
5811 | ** METHOD: sqlite3 |
5812 | ** |
5813 | ** ^These functions add, remove, or modify a [collation] associated |
5814 | ** with the [database connection] specified as the first argument. |
5815 | ** |
5816 | ** ^The name of the collation is a UTF-8 string |
5817 | ** for sqlite3_create_collation() and sqlite3_create_collation_v2() |
5818 | ** and a UTF-16 string in native byte order for sqlite3_create_collation16(). |
5819 | ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are |
5820 | ** considered to be the same name. |
5821 | ** |
5822 | ** ^(The third argument (eTextRep) must be one of the constants: |
5823 | ** <ul> |
5824 | ** <li> [SQLITE_UTF8], |
5825 | ** <li> [SQLITE_UTF16LE], |
5826 | ** <li> [SQLITE_UTF16BE], |
5827 | ** <li> [SQLITE_UTF16], or |
5828 | ** <li> [SQLITE_UTF16_ALIGNED]. |
5829 | ** </ul>)^ |
5830 | ** ^The eTextRep argument determines the encoding of strings passed |
5831 | ** to the collating function callback, xCompare. |
5832 | ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep |
5833 | ** force strings to be UTF16 with native byte order. |
5834 | ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin |
5835 | ** on an even byte address. |
5836 | ** |
5837 | ** ^The fourth argument, pArg, is an application data pointer that is passed |
5838 | ** through as the first argument to the collating function callback. |
5839 | ** |
5840 | ** ^The fifth argument, xCompare, is a pointer to the collating function. |
5841 | ** ^Multiple collating functions can be registered using the same name but |
5842 | ** with different eTextRep parameters and SQLite will use whichever |
5843 | ** function requires the least amount of data transformation. |
5844 | ** ^If the xCompare argument is NULL then the collating function is |
5845 | ** deleted. ^When all collating functions having the same name are deleted, |
5846 | ** that collation is no longer usable. |
5847 | ** |
5848 | ** ^The collating function callback is invoked with a copy of the pArg |
5849 | ** application data pointer and with two strings in the encoding specified |
5850 | ** by the eTextRep argument. The two integer parameters to the collating |
5851 | ** function callback are the length of the two strings, in bytes. The collating |
5852 | ** function must return an integer that is negative, zero, or positive |
5853 | ** if the first string is less than, equal to, or greater than the second, |
5854 | ** respectively. A collating function must always return the same answer |
5855 | ** given the same inputs. If two or more collating functions are registered |
5856 | ** to the same collation name (using different eTextRep values) then all |
5857 | ** must give an equivalent answer when invoked with equivalent strings. |
5858 | ** The collating function must obey the following properties for all |
5859 | ** strings A, B, and C: |
5860 | ** |
5861 | ** <ol> |
5862 | ** <li> If A==B then B==A. |
5863 | ** <li> If A==B and B==C then A==C. |
5864 | ** <li> If A<B THEN B>A. |
5865 | ** <li> If A<B and B<C then A<C. |
5866 | ** </ol> |
5867 | ** |
5868 | ** If a collating function fails any of the above constraints and that |
5869 | ** collating function is registered and used, then the behavior of SQLite |
5870 | ** is undefined. |
5871 | ** |
5872 | ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation() |
5873 | ** with the addition that the xDestroy callback is invoked on pArg when |
5874 | ** the collating function is deleted. |
5875 | ** ^Collating functions are deleted when they are overridden by later |
5876 | ** calls to the collation creation functions or when the |
5877 | ** [database connection] is closed using [sqlite3_close()]. |
5878 | ** |
5879 | ** ^The xDestroy callback is <u>not</u> called if the |
5880 | ** sqlite3_create_collation_v2() function fails. Applications that invoke |
5881 | ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should |
5882 | ** check the return code and dispose of the application data pointer |
5883 | ** themselves rather than expecting SQLite to deal with it for them. |
5884 | ** This is different from every other SQLite interface. The inconsistency |
5885 | ** is unfortunate but cannot be changed without breaking backwards |
5886 | ** compatibility. |
5887 | ** |
5888 | ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. |
5889 | */ |
5890 | SQLITE_API int sqlite3_create_collation( |
5891 | sqlite3*, |
5892 | const char *zName, |
5893 | int eTextRep, |
5894 | void *pArg, |
5895 | int(*xCompare)(void*,int,const void*,int,const void*) |
5896 | ); |
5897 | SQLITE_API int sqlite3_create_collation_v2( |
5898 | sqlite3*, |
5899 | const char *zName, |
5900 | int eTextRep, |
5901 | void *pArg, |
5902 | int(*xCompare)(void*,int,const void*,int,const void*), |
5903 | void(*xDestroy)(void*) |
5904 | ); |
5905 | SQLITE_API int sqlite3_create_collation16( |
5906 | sqlite3*, |
5907 | const void *zName, |
5908 | int eTextRep, |
5909 | void *pArg, |
5910 | int(*xCompare)(void*,int,const void*,int,const void*) |
5911 | ); |
5912 | |
5913 | /* |
5914 | ** CAPI3REF: Collation Needed Callbacks |
5915 | ** METHOD: sqlite3 |
5916 | ** |
5917 | ** ^To avoid having to register all collation sequences before a database |
5918 | ** can be used, a single callback function may be registered with the |
5919 | ** [database connection] to be invoked whenever an undefined collation |
5920 | ** sequence is required. |
5921 | ** |
5922 | ** ^If the function is registered using the sqlite3_collation_needed() API, |
5923 | ** then it is passed the names of undefined collation sequences as strings |
5924 | ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used, |
5925 | ** the names are passed as UTF-16 in machine native byte order. |
5926 | ** ^A call to either function replaces the existing collation-needed callback. |
5927 | ** |
5928 | ** ^(When the callback is invoked, the first argument passed is a copy |
5929 | ** of the second argument to sqlite3_collation_needed() or |
5930 | ** sqlite3_collation_needed16(). The second argument is the database |
5931 | ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], |
5932 | ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation |
5933 | ** sequence function required. The fourth parameter is the name of the |
5934 | ** required collation sequence.)^ |
5935 | ** |
5936 | ** The callback function should register the desired collation using |
5937 | ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or |
5938 | ** [sqlite3_create_collation_v2()]. |
5939 | */ |
5940 | SQLITE_API int sqlite3_collation_needed( |
5941 | sqlite3*, |
5942 | void*, |
5943 | void(*)(void*,sqlite3*,int eTextRep,const char*) |
5944 | ); |
5945 | SQLITE_API int sqlite3_collation_needed16( |
5946 | sqlite3*, |
5947 | void*, |
5948 | void(*)(void*,sqlite3*,int eTextRep,const void*) |
5949 | ); |
5950 | |
5951 | #ifdef SQLITE_ENABLE_CEROD |
5952 | /* |
5953 | ** Specify the activation key for a CEROD database. Unless |
5954 | ** activated, none of the CEROD routines will work. |
5955 | */ |
5956 | SQLITE_API void sqlite3_activate_cerod( |
5957 | const char *zPassPhrase /* Activation phrase */ |
5958 | ); |
5959 | #endif |
5960 | |
5961 | /* |
5962 | ** CAPI3REF: Suspend Execution For A Short Time |
5963 | ** |
5964 | ** The sqlite3_sleep() function causes the current thread to suspend execution |
5965 | ** for at least a number of milliseconds specified in its parameter. |
5966 | ** |
5967 | ** If the operating system does not support sleep requests with |
5968 | ** millisecond time resolution, then the time will be rounded up to |
5969 | ** the nearest second. The number of milliseconds of sleep actually |
5970 | ** requested from the operating system is returned. |
5971 | ** |
5972 | ** ^SQLite implements this interface by calling the xSleep() |
5973 | ** method of the default [sqlite3_vfs] object. If the xSleep() method |
5974 | ** of the default VFS is not implemented correctly, or not implemented at |
5975 | ** all, then the behavior of sqlite3_sleep() may deviate from the description |
5976 | ** in the previous paragraphs. |
5977 | */ |
5978 | SQLITE_API int sqlite3_sleep(int); |
5979 | |
5980 | /* |
5981 | ** CAPI3REF: Name Of The Folder Holding Temporary Files |
5982 | ** |
5983 | ** ^(If this global variable is made to point to a string which is |
5984 | ** the name of a folder (a.k.a. directory), then all temporary files |
5985 | ** created by SQLite when using a built-in [sqlite3_vfs | VFS] |
5986 | ** will be placed in that directory.)^ ^If this variable |
5987 | ** is a NULL pointer, then SQLite performs a search for an appropriate |
5988 | ** temporary file directory. |
5989 | ** |
5990 | ** Applications are strongly discouraged from using this global variable. |
5991 | ** It is required to set a temporary folder on Windows Runtime (WinRT). |
5992 | ** But for all other platforms, it is highly recommended that applications |
5993 | ** neither read nor write this variable. This global variable is a relic |
5994 | ** that exists for backwards compatibility of legacy applications and should |
5995 | ** be avoided in new projects. |
5996 | ** |
5997 | ** It is not safe to read or modify this variable in more than one |
5998 | ** thread at a time. It is not safe to read or modify this variable |
5999 | ** if a [database connection] is being used at the same time in a separate |
6000 | ** thread. |
6001 | ** It is intended that this variable be set once |
6002 | ** as part of process initialization and before any SQLite interface |
6003 | ** routines have been called and that this variable remain unchanged |
6004 | ** thereafter. |
6005 | ** |
6006 | ** ^The [temp_store_directory pragma] may modify this variable and cause |
6007 | ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, |
6008 | ** the [temp_store_directory pragma] always assumes that any string |
6009 | ** that this variable points to is held in memory obtained from |
6010 | ** [sqlite3_malloc] and the pragma may attempt to free that memory |
6011 | ** using [sqlite3_free]. |
6012 | ** Hence, if this variable is modified directly, either it should be |
6013 | ** made NULL or made to point to memory obtained from [sqlite3_malloc] |
6014 | ** or else the use of the [temp_store_directory pragma] should be avoided. |
6015 | ** Except when requested by the [temp_store_directory pragma], SQLite |
6016 | ** does not free the memory that sqlite3_temp_directory points to. If |
6017 | ** the application wants that memory to be freed, it must do |
6018 | ** so itself, taking care to only do so after all [database connection] |
6019 | ** objects have been destroyed. |
6020 | ** |
6021 | ** <b>Note to Windows Runtime users:</b> The temporary directory must be set |
6022 | ** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various |
6023 | ** features that require the use of temporary files may fail. Here is an |
6024 | ** example of how to do this using C++ with the Windows Runtime: |
6025 | ** |
6026 | ** <blockquote><pre> |
6027 | ** LPCWSTR zPath = Windows::Storage::ApplicationData::Current-> |
6028 | ** TemporaryFolder->Path->Data(); |
6029 | ** char zPathBuf[MAX_PATH + 1]; |
6030 | ** memset(zPathBuf, 0, sizeof(zPathBuf)); |
6031 | ** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf), |
6032 | ** NULL, NULL); |
6033 | ** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf); |
6034 | ** </pre></blockquote> |
6035 | */ |
6036 | SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory; |
6037 | |
6038 | /* |
6039 | ** CAPI3REF: Name Of The Folder Holding Database Files |
6040 | ** |
6041 | ** ^(If this global variable is made to point to a string which is |
6042 | ** the name of a folder (a.k.a. directory), then all database files |
6043 | ** specified with a relative pathname and created or accessed by |
6044 | ** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed |
6045 | ** to be relative to that directory.)^ ^If this variable is a NULL |
6046 | ** pointer, then SQLite assumes that all database files specified |
6047 | ** with a relative pathname are relative to the current directory |
6048 | ** for the process. Only the windows VFS makes use of this global |
6049 | ** variable; it is ignored by the unix VFS. |
6050 | ** |
6051 | ** Changing the value of this variable while a database connection is |
6052 | ** open can result in a corrupt database. |
6053 | ** |
6054 | ** It is not safe to read or modify this variable in more than one |
6055 | ** thread at a time. It is not safe to read or modify this variable |
6056 | ** if a [database connection] is being used at the same time in a separate |
6057 | ** thread. |
6058 | ** It is intended that this variable be set once |
6059 | ** as part of process initialization and before any SQLite interface |
6060 | ** routines have been called and that this variable remain unchanged |
6061 | ** thereafter. |
6062 | ** |
6063 | ** ^The [data_store_directory pragma] may modify this variable and cause |
6064 | ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, |
6065 | ** the [data_store_directory pragma] always assumes that any string |
6066 | ** that this variable points to is held in memory obtained from |
6067 | ** [sqlite3_malloc] and the pragma may attempt to free that memory |
6068 | ** using [sqlite3_free]. |
6069 | ** Hence, if this variable is modified directly, either it should be |
6070 | ** made NULL or made to point to memory obtained from [sqlite3_malloc] |
6071 | ** or else the use of the [data_store_directory pragma] should be avoided. |
6072 | */ |
6073 | SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory; |
6074 | |
6075 | /* |
6076 | ** CAPI3REF: Win32 Specific Interface |
6077 | ** |
6078 | ** These interfaces are available only on Windows. The |
6079 | ** [sqlite3_win32_set_directory] interface is used to set the value associated |
6080 | ** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to |
6081 | ** zValue, depending on the value of the type parameter. The zValue parameter |
6082 | ** should be NULL to cause the previous value to be freed via [sqlite3_free]; |
6083 | ** a non-NULL value will be copied into memory obtained from [sqlite3_malloc] |
6084 | ** prior to being used. The [sqlite3_win32_set_directory] interface returns |
6085 | ** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported, |
6086 | ** or [SQLITE_NOMEM] if memory could not be allocated. The value of the |
6087 | ** [sqlite3_data_directory] variable is intended to act as a replacement for |
6088 | ** the current directory on the sub-platforms of Win32 where that concept is |
6089 | ** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and |
6090 | ** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the |
6091 | ** sqlite3_win32_set_directory interface except the string parameter must be |
6092 | ** UTF-8 or UTF-16, respectively. |
6093 | */ |
6094 | SQLITE_API int sqlite3_win32_set_directory( |
6095 | unsigned long type, /* Identifier for directory being set or reset */ |
6096 | void *zValue /* New value for directory being set or reset */ |
6097 | ); |
6098 | SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue); |
6099 | SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue); |
6100 | |
6101 | /* |
6102 | ** CAPI3REF: Win32 Directory Types |
6103 | ** |
6104 | ** These macros are only available on Windows. They define the allowed values |
6105 | ** for the type argument to the [sqlite3_win32_set_directory] interface. |
6106 | */ |
6107 | #define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1 |
6108 | #define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2 |
6109 | |
6110 | /* |
6111 | ** CAPI3REF: Test For Auto-Commit Mode |
6112 | ** KEYWORDS: {autocommit mode} |
6113 | ** METHOD: sqlite3 |
6114 | ** |
6115 | ** ^The sqlite3_get_autocommit() interface returns non-zero or |
6116 | ** zero if the given database connection is or is not in autocommit mode, |
6117 | ** respectively. ^Autocommit mode is on by default. |
6118 | ** ^Autocommit mode is disabled by a [BEGIN] statement. |
6119 | ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. |
6120 | ** |
6121 | ** If certain kinds of errors occur on a statement within a multi-statement |
6122 | ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], |
6123 | ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the |
6124 | ** transaction might be rolled back automatically. The only way to |
6125 | ** find out whether SQLite automatically rolled back the transaction after |
6126 | ** an error is to use this function. |
6127 | ** |
6128 | ** If another thread changes the autocommit status of the database |
6129 | ** connection while this routine is running, then the return value |
6130 | ** is undefined. |
6131 | */ |
6132 | SQLITE_API int sqlite3_get_autocommit(sqlite3*); |
6133 | |
6134 | /* |
6135 | ** CAPI3REF: Find The Database Handle Of A Prepared Statement |
6136 | ** METHOD: sqlite3_stmt |
6137 | ** |
6138 | ** ^The sqlite3_db_handle interface returns the [database connection] handle |
6139 | ** to which a [prepared statement] belongs. ^The [database connection] |
6140 | ** returned by sqlite3_db_handle is the same [database connection] |
6141 | ** that was the first argument |
6142 | ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to |
6143 | ** create the statement in the first place. |
6144 | */ |
6145 | SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*); |
6146 | |
6147 | /* |
6148 | ** CAPI3REF: Return The Filename For A Database Connection |
6149 | ** METHOD: sqlite3 |
6150 | ** |
6151 | ** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename |
6152 | ** associated with database N of connection D. |
6153 | ** ^If there is no attached database N on the database |
6154 | ** connection D, or if database N is a temporary or in-memory database, then |
6155 | ** this function will return either a NULL pointer or an empty string. |
6156 | ** |
6157 | ** ^The string value returned by this routine is owned and managed by |
6158 | ** the database connection. ^The value will be valid until the database N |
6159 | ** is [DETACH]-ed or until the database connection closes. |
6160 | ** |
6161 | ** ^The filename returned by this function is the output of the |
6162 | ** xFullPathname method of the [VFS]. ^In other words, the filename |
6163 | ** will be an absolute pathname, even if the filename used |
6164 | ** to open the database originally was a URI or relative pathname. |
6165 | ** |
6166 | ** If the filename pointer returned by this routine is not NULL, then it |
6167 | ** can be used as the filename input parameter to these routines: |
6168 | ** <ul> |
6169 | ** <li> [sqlite3_uri_parameter()] |
6170 | ** <li> [sqlite3_uri_boolean()] |
6171 | ** <li> [sqlite3_uri_int64()] |
6172 | ** <li> [sqlite3_filename_database()] |
6173 | ** <li> [sqlite3_filename_journal()] |
6174 | ** <li> [sqlite3_filename_wal()] |
6175 | ** </ul> |
6176 | */ |
6177 | SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName); |
6178 | |
6179 | /* |
6180 | ** CAPI3REF: Determine if a database is read-only |
6181 | ** METHOD: sqlite3 |
6182 | ** |
6183 | ** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N |
6184 | ** of connection D is read-only, 0 if it is read/write, or -1 if N is not |
6185 | ** the name of a database on connection D. |
6186 | */ |
6187 | SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName); |
6188 | |
6189 | /* |
6190 | ** CAPI3REF: Find the next prepared statement |
6191 | ** METHOD: sqlite3 |
6192 | ** |
6193 | ** ^This interface returns a pointer to the next [prepared statement] after |
6194 | ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL |
6195 | ** then this interface returns a pointer to the first prepared statement |
6196 | ** associated with the database connection pDb. ^If no prepared statement |
6197 | ** satisfies the conditions of this routine, it returns NULL. |
6198 | ** |
6199 | ** The [database connection] pointer D in a call to |
6200 | ** [sqlite3_next_stmt(D,S)] must refer to an open database |
6201 | ** connection and in particular must not be a NULL pointer. |
6202 | */ |
6203 | SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); |
6204 | |
6205 | /* |
6206 | ** CAPI3REF: Commit And Rollback Notification Callbacks |
6207 | ** METHOD: sqlite3 |
6208 | ** |
6209 | ** ^The sqlite3_commit_hook() interface registers a callback |
6210 | ** function to be invoked whenever a transaction is [COMMIT | committed]. |
6211 | ** ^Any callback set by a previous call to sqlite3_commit_hook() |
6212 | ** for the same database connection is overridden. |
6213 | ** ^The sqlite3_rollback_hook() interface registers a callback |
6214 | ** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. |
6215 | ** ^Any callback set by a previous call to sqlite3_rollback_hook() |
6216 | ** for the same database connection is overridden. |
6217 | ** ^The pArg argument is passed through to the callback. |
6218 | ** ^If the callback on a commit hook function returns non-zero, |
6219 | ** then the commit is converted into a rollback. |
6220 | ** |
6221 | ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions |
6222 | ** return the P argument from the previous call of the same function |
6223 | ** on the same [database connection] D, or NULL for |
6224 | ** the first call for each function on D. |
6225 | ** |
6226 | ** The commit and rollback hook callbacks are not reentrant. |
6227 | ** The callback implementation must not do anything that will modify |
6228 | ** the database connection that invoked the callback. Any actions |
6229 | ** to modify the database connection must be deferred until after the |
6230 | ** completion of the [sqlite3_step()] call that triggered the commit |
6231 | ** or rollback hook in the first place. |
6232 | ** Note that running any other SQL statements, including SELECT statements, |
6233 | ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify |
6234 | ** the database connections for the meaning of "modify" in this paragraph. |
6235 | ** |
6236 | ** ^Registering a NULL function disables the callback. |
6237 | ** |
6238 | ** ^When the commit hook callback routine returns zero, the [COMMIT] |
6239 | ** operation is allowed to continue normally. ^If the commit hook |
6240 | ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. |
6241 | ** ^The rollback hook is invoked on a rollback that results from a commit |
6242 | ** hook returning non-zero, just as it would be with any other rollback. |
6243 | ** |
6244 | ** ^For the purposes of this API, a transaction is said to have been |
6245 | ** rolled back if an explicit "ROLLBACK" statement is executed, or |
6246 | ** an error or constraint causes an implicit rollback to occur. |
6247 | ** ^The rollback callback is not invoked if a transaction is |
6248 | ** automatically rolled back because the database connection is closed. |
6249 | ** |
6250 | ** See also the [sqlite3_update_hook()] interface. |
6251 | */ |
6252 | SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); |
6253 | SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); |
6254 | |
6255 | /* |
6256 | ** CAPI3REF: Data Change Notification Callbacks |
6257 | ** METHOD: sqlite3 |
6258 | ** |
6259 | ** ^The sqlite3_update_hook() interface registers a callback function |
6260 | ** with the [database connection] identified by the first argument |
6261 | ** to be invoked whenever a row is updated, inserted or deleted in |
6262 | ** a [rowid table]. |
6263 | ** ^Any callback set by a previous call to this function |
6264 | ** for the same database connection is overridden. |
6265 | ** |
6266 | ** ^The second argument is a pointer to the function to invoke when a |
6267 | ** row is updated, inserted or deleted in a rowid table. |
6268 | ** ^The first argument to the callback is a copy of the third argument |
6269 | ** to sqlite3_update_hook(). |
6270 | ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], |
6271 | ** or [SQLITE_UPDATE], depending on the operation that caused the callback |
6272 | ** to be invoked. |
6273 | ** ^The third and fourth arguments to the callback contain pointers to the |
6274 | ** database and table name containing the affected row. |
6275 | ** ^The final callback parameter is the [rowid] of the row. |
6276 | ** ^In the case of an update, this is the [rowid] after the update takes place. |
6277 | ** |
6278 | ** ^(The update hook is not invoked when internal system tables are |
6279 | ** modified (i.e. sqlite_sequence).)^ |
6280 | ** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified. |
6281 | ** |
6282 | ** ^In the current implementation, the update hook |
6283 | ** is not invoked when conflicting rows are deleted because of an |
6284 | ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook |
6285 | ** invoked when rows are deleted using the [truncate optimization]. |
6286 | ** The exceptions defined in this paragraph might change in a future |
6287 | ** release of SQLite. |
6288 | ** |
6289 | ** The update hook implementation must not do anything that will modify |
6290 | ** the database connection that invoked the update hook. Any actions |
6291 | ** to modify the database connection must be deferred until after the |
6292 | ** completion of the [sqlite3_step()] call that triggered the update hook. |
6293 | ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their |
6294 | ** database connections for the meaning of "modify" in this paragraph. |
6295 | ** |
6296 | ** ^The sqlite3_update_hook(D,C,P) function |
6297 | ** returns the P argument from the previous call |
6298 | ** on the same [database connection] D, or NULL for |
6299 | ** the first call on D. |
6300 | ** |
6301 | ** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()], |
6302 | ** and [sqlite3_preupdate_hook()] interfaces. |
6303 | */ |
6304 | SQLITE_API void *sqlite3_update_hook( |
6305 | sqlite3*, |
6306 | void(*)(void *,int ,char const *,char const *,sqlite3_int64), |
6307 | void* |
6308 | ); |
6309 | |
6310 | /* |
6311 | ** CAPI3REF: Enable Or Disable Shared Pager Cache |
6312 | ** |
6313 | ** ^(This routine enables or disables the sharing of the database cache |
6314 | ** and schema data structures between [database connection | connections] |
6315 | ** to the same database. Sharing is enabled if the argument is true |
6316 | ** and disabled if the argument is false.)^ |
6317 | ** |
6318 | ** ^Cache sharing is enabled and disabled for an entire process. |
6319 | ** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]). |
6320 | ** In prior versions of SQLite, |
6321 | ** sharing was enabled or disabled for each thread separately. |
6322 | ** |
6323 | ** ^(The cache sharing mode set by this interface effects all subsequent |
6324 | ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. |
6325 | ** Existing database connections continue to use the sharing mode |
6326 | ** that was in effect at the time they were opened.)^ |
6327 | ** |
6328 | ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled |
6329 | ** successfully. An [error code] is returned otherwise.)^ |
6330 | ** |
6331 | ** ^Shared cache is disabled by default. It is recommended that it stay |
6332 | ** that way. In other words, do not use this routine. This interface |
6333 | ** continues to be provided for historical compatibility, but its use is |
6334 | ** discouraged. Any use of shared cache is discouraged. If shared cache |
6335 | ** must be used, it is recommended that shared cache only be enabled for |
6336 | ** individual database connections using the [sqlite3_open_v2()] interface |
6337 | ** with the [SQLITE_OPEN_SHAREDCACHE] flag. |
6338 | ** |
6339 | ** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0 |
6340 | ** and will always return SQLITE_MISUSE. On those systems, |
6341 | ** shared cache mode should be enabled per-database connection via |
6342 | ** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE]. |
6343 | ** |
6344 | ** This interface is threadsafe on processors where writing a |
6345 | ** 32-bit integer is atomic. |
6346 | ** |
6347 | ** See Also: [SQLite Shared-Cache Mode] |
6348 | */ |
6349 | SQLITE_API int sqlite3_enable_shared_cache(int); |
6350 | |
6351 | /* |
6352 | ** CAPI3REF: Attempt To Free Heap Memory |
6353 | ** |
6354 | ** ^The sqlite3_release_memory() interface attempts to free N bytes |
6355 | ** of heap memory by deallocating non-essential memory allocations |
6356 | ** held by the database library. Memory used to cache database |
6357 | ** pages to improve performance is an example of non-essential memory. |
6358 | ** ^sqlite3_release_memory() returns the number of bytes actually freed, |
6359 | ** which might be more or less than the amount requested. |
6360 | ** ^The sqlite3_release_memory() routine is a no-op returning zero |
6361 | ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT]. |
6362 | ** |
6363 | ** See also: [sqlite3_db_release_memory()] |
6364 | */ |
6365 | SQLITE_API int sqlite3_release_memory(int); |
6366 | |
6367 | /* |
6368 | ** CAPI3REF: Free Memory Used By A Database Connection |
6369 | ** METHOD: sqlite3 |
6370 | ** |
6371 | ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap |
6372 | ** memory as possible from database connection D. Unlike the |
6373 | ** [sqlite3_release_memory()] interface, this interface is in effect even |
6374 | ** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is |
6375 | ** omitted. |
6376 | ** |
6377 | ** See also: [sqlite3_release_memory()] |
6378 | */ |
6379 | SQLITE_API int sqlite3_db_release_memory(sqlite3*); |
6380 | |
6381 | /* |
6382 | ** CAPI3REF: Impose A Limit On Heap Size |
6383 | ** |
6384 | ** These interfaces impose limits on the amount of heap memory that will be |
6385 | ** by all database connections within a single process. |
6386 | ** |
6387 | ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the |
6388 | ** soft limit on the amount of heap memory that may be allocated by SQLite. |
6389 | ** ^SQLite strives to keep heap memory utilization below the soft heap |
6390 | ** limit by reducing the number of pages held in the page cache |
6391 | ** as heap memory usages approaches the limit. |
6392 | ** ^The soft heap limit is "soft" because even though SQLite strives to stay |
6393 | ** below the limit, it will exceed the limit rather than generate |
6394 | ** an [SQLITE_NOMEM] error. In other words, the soft heap limit |
6395 | ** is advisory only. |
6396 | ** |
6397 | ** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of |
6398 | ** N bytes on the amount of memory that will be allocated. ^The |
6399 | ** sqlite3_hard_heap_limit64(N) interface is similar to |
6400 | ** sqlite3_soft_heap_limit64(N) except that memory allocations will fail |
6401 | ** when the hard heap limit is reached. |
6402 | ** |
6403 | ** ^The return value from both sqlite3_soft_heap_limit64() and |
6404 | ** sqlite3_hard_heap_limit64() is the size of |
6405 | ** the heap limit prior to the call, or negative in the case of an |
6406 | ** error. ^If the argument N is negative |
6407 | ** then no change is made to the heap limit. Hence, the current |
6408 | ** size of heap limits can be determined by invoking |
6409 | ** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1). |
6410 | ** |
6411 | ** ^Setting the heap limits to zero disables the heap limiter mechanism. |
6412 | ** |
6413 | ** ^The soft heap limit may not be greater than the hard heap limit. |
6414 | ** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N) |
6415 | ** is invoked with a value of N that is greater than the hard heap limit, |
6416 | ** the the soft heap limit is set to the value of the hard heap limit. |
6417 | ** ^The soft heap limit is automatically enabled whenever the hard heap |
6418 | ** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and |
6419 | ** the soft heap limit is outside the range of 1..N, then the soft heap |
6420 | ** limit is set to N. ^Invoking sqlite3_soft_heap_limit64(0) when the |
6421 | ** hard heap limit is enabled makes the soft heap limit equal to the |
6422 | ** hard heap limit. |
6423 | ** |
6424 | ** The memory allocation limits can also be adjusted using |
6425 | ** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit]. |
6426 | ** |
6427 | ** ^(The heap limits are not enforced in the current implementation |
6428 | ** if one or more of following conditions are true: |
6429 | ** |
6430 | ** <ul> |
6431 | ** <li> The limit value is set to zero. |
6432 | ** <li> Memory accounting is disabled using a combination of the |
6433 | ** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and |
6434 | ** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option. |
6435 | ** <li> An alternative page cache implementation is specified using |
6436 | ** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...). |
6437 | ** <li> The page cache allocates from its own memory pool supplied |
6438 | ** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than |
6439 | ** from the heap. |
6440 | ** </ul>)^ |
6441 | ** |
6442 | ** The circumstances under which SQLite will enforce the heap limits may |
6443 | ** changes in future releases of SQLite. |
6444 | */ |
6445 | SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N); |
6446 | SQLITE_API sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N); |
6447 | |
6448 | /* |
6449 | ** CAPI3REF: Deprecated Soft Heap Limit Interface |
6450 | ** DEPRECATED |
6451 | ** |
6452 | ** This is a deprecated version of the [sqlite3_soft_heap_limit64()] |
6453 | ** interface. This routine is provided for historical compatibility |
6454 | ** only. All new applications should use the |
6455 | ** [sqlite3_soft_heap_limit64()] interface rather than this one. |
6456 | */ |
6457 | SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N); |
6458 | |
6459 | |
6460 | /* |
6461 | ** CAPI3REF: Extract Metadata About A Column Of A Table |
6462 | ** METHOD: sqlite3 |
6463 | ** |
6464 | ** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns |
6465 | ** information about column C of table T in database D |
6466 | ** on [database connection] X.)^ ^The sqlite3_table_column_metadata() |
6467 | ** interface returns SQLITE_OK and fills in the non-NULL pointers in |
6468 | ** the final five arguments with appropriate values if the specified |
6469 | ** column exists. ^The sqlite3_table_column_metadata() interface returns |
6470 | ** SQLITE_ERROR if the specified column does not exist. |
6471 | ** ^If the column-name parameter to sqlite3_table_column_metadata() is a |
6472 | ** NULL pointer, then this routine simply checks for the existence of the |
6473 | ** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it |
6474 | ** does not. If the table name parameter T in a call to |
6475 | ** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is |
6476 | ** undefined behavior. |
6477 | ** |
6478 | ** ^The column is identified by the second, third and fourth parameters to |
6479 | ** this function. ^(The second parameter is either the name of the database |
6480 | ** (i.e. "main", "temp", or an attached database) containing the specified |
6481 | ** table or NULL.)^ ^If it is NULL, then all attached databases are searched |
6482 | ** for the table using the same algorithm used by the database engine to |
6483 | ** resolve unqualified table references. |
6484 | ** |
6485 | ** ^The third and fourth parameters to this function are the table and column |
6486 | ** name of the desired column, respectively. |
6487 | ** |
6488 | ** ^Metadata is returned by writing to the memory locations passed as the 5th |
6489 | ** and subsequent parameters to this function. ^Any of these arguments may be |
6490 | ** NULL, in which case the corresponding element of metadata is omitted. |
6491 | ** |
6492 | ** ^(<blockquote> |
6493 | ** <table border="1"> |
6494 | ** <tr><th> Parameter <th> Output<br>Type <th> Description |
6495 | ** |
6496 | ** <tr><td> 5th <td> const char* <td> Data type |
6497 | ** <tr><td> 6th <td> const char* <td> Name of default collation sequence |
6498 | ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint |
6499 | ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY |
6500 | ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT] |
6501 | ** </table> |
6502 | ** </blockquote>)^ |
6503 | ** |
6504 | ** ^The memory pointed to by the character pointers returned for the |
6505 | ** declaration type and collation sequence is valid until the next |
6506 | ** call to any SQLite API function. |
6507 | ** |
6508 | ** ^If the specified table is actually a view, an [error code] is returned. |
6509 | ** |
6510 | ** ^If the specified column is "rowid", "oid" or "_rowid_" and the table |
6511 | ** is not a [WITHOUT ROWID] table and an |
6512 | ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output |
6513 | ** parameters are set for the explicitly declared column. ^(If there is no |
6514 | ** [INTEGER PRIMARY KEY] column, then the outputs |
6515 | ** for the [rowid] are set as follows: |
6516 | ** |
6517 | ** <pre> |
6518 | ** data type: "INTEGER" |
6519 | ** collation sequence: "BINARY" |
6520 | ** not null: 0 |
6521 | ** primary key: 1 |
6522 | ** auto increment: 0 |
6523 | ** </pre>)^ |
6524 | ** |
6525 | ** ^This function causes all database schemas to be read from disk and |
6526 | ** parsed, if that has not already been done, and returns an error if |
6527 | ** any errors are encountered while loading the schema. |
6528 | */ |
6529 | SQLITE_API int sqlite3_table_column_metadata( |
6530 | sqlite3 *db, /* Connection handle */ |
6531 | const char *zDbName, /* Database name or NULL */ |
6532 | const char *zTableName, /* Table name */ |
6533 | const char *zColumnName, /* Column name */ |
6534 | char const **pzDataType, /* OUTPUT: Declared data type */ |
6535 | char const **pzCollSeq, /* OUTPUT: Collation sequence name */ |
6536 | int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ |
6537 | int *pPrimaryKey, /* OUTPUT: True if column part of PK */ |
6538 | int *pAutoinc /* OUTPUT: True if column is auto-increment */ |
6539 | ); |
6540 | |
6541 | /* |
6542 | ** CAPI3REF: Load An Extension |
6543 | ** METHOD: sqlite3 |
6544 | ** |
6545 | ** ^This interface loads an SQLite extension library from the named file. |
6546 | ** |
6547 | ** ^The sqlite3_load_extension() interface attempts to load an |
6548 | ** [SQLite extension] library contained in the file zFile. If |
6549 | ** the file cannot be loaded directly, attempts are made to load |
6550 | ** with various operating-system specific extensions added. |
6551 | ** So for example, if "samplelib" cannot be loaded, then names like |
6552 | ** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might |
6553 | ** be tried also. |
6554 | ** |
6555 | ** ^The entry point is zProc. |
6556 | ** ^(zProc may be 0, in which case SQLite will try to come up with an |
6557 | ** entry point name on its own. It first tries "sqlite3_extension_init". |
6558 | ** If that does not work, it constructs a name "sqlite3_X_init" where the |
6559 | ** X is consists of the lower-case equivalent of all ASCII alphabetic |
6560 | ** characters in the filename from the last "/" to the first following |
6561 | ** "." and omitting any initial "lib".)^ |
6562 | ** ^The sqlite3_load_extension() interface returns |
6563 | ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. |
6564 | ** ^If an error occurs and pzErrMsg is not 0, then the |
6565 | ** [sqlite3_load_extension()] interface shall attempt to |
6566 | ** fill *pzErrMsg with error message text stored in memory |
6567 | ** obtained from [sqlite3_malloc()]. The calling function |
6568 | ** should free this memory by calling [sqlite3_free()]. |
6569 | ** |
6570 | ** ^Extension loading must be enabled using |
6571 | ** [sqlite3_enable_load_extension()] or |
6572 | ** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL) |
6573 | ** prior to calling this API, |
6574 | ** otherwise an error will be returned. |
6575 | ** |
6576 | ** <b>Security warning:</b> It is recommended that the |
6577 | ** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this |
6578 | ** interface. The use of the [sqlite3_enable_load_extension()] interface |
6579 | ** should be avoided. This will keep the SQL function [load_extension()] |
6580 | ** disabled and prevent SQL injections from giving attackers |
6581 | ** access to extension loading capabilities. |
6582 | ** |
6583 | ** See also the [load_extension() SQL function]. |
6584 | */ |
6585 | SQLITE_API int sqlite3_load_extension( |
6586 | sqlite3 *db, /* Load the extension into this database connection */ |
6587 | const char *zFile, /* Name of the shared library containing extension */ |
6588 | const char *zProc, /* Entry point. Derived from zFile if 0 */ |
6589 | char **pzErrMsg /* Put error message here if not 0 */ |
6590 | ); |
6591 | |
6592 | /* |
6593 | ** CAPI3REF: Enable Or Disable Extension Loading |
6594 | ** METHOD: sqlite3 |
6595 | ** |
6596 | ** ^So as not to open security holes in older applications that are |
6597 | ** unprepared to deal with [extension loading], and as a means of disabling |
6598 | ** [extension loading] while evaluating user-entered SQL, the following API |
6599 | ** is provided to turn the [sqlite3_load_extension()] mechanism on and off. |
6600 | ** |
6601 | ** ^Extension loading is off by default. |
6602 | ** ^Call the sqlite3_enable_load_extension() routine with onoff==1 |
6603 | ** to turn extension loading on and call it with onoff==0 to turn |
6604 | ** it back off again. |
6605 | ** |
6606 | ** ^This interface enables or disables both the C-API |
6607 | ** [sqlite3_load_extension()] and the SQL function [load_extension()]. |
6608 | ** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..) |
6609 | ** to enable or disable only the C-API.)^ |
6610 | ** |
6611 | ** <b>Security warning:</b> It is recommended that extension loading |
6612 | ** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method |
6613 | ** rather than this interface, so the [load_extension()] SQL function |
6614 | ** remains disabled. This will prevent SQL injections from giving attackers |
6615 | ** access to extension loading capabilities. |
6616 | */ |
6617 | SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff); |
6618 | |
6619 | /* |
6620 | ** CAPI3REF: Automatically Load Statically Linked Extensions |
6621 | ** |
6622 | ** ^This interface causes the xEntryPoint() function to be invoked for |
6623 | ** each new [database connection] that is created. The idea here is that |
6624 | ** xEntryPoint() is the entry point for a statically linked [SQLite extension] |
6625 | ** that is to be automatically loaded into all new database connections. |
6626 | ** |
6627 | ** ^(Even though the function prototype shows that xEntryPoint() takes |
6628 | ** no arguments and returns void, SQLite invokes xEntryPoint() with three |
6629 | ** arguments and expects an integer result as if the signature of the |
6630 | ** entry point where as follows: |
6631 | ** |
6632 | ** <blockquote><pre> |
6633 | ** int xEntryPoint( |
6634 | ** sqlite3 *db, |
6635 | ** const char **pzErrMsg, |
6636 | ** const struct sqlite3_api_routines *pThunk |
6637 | ** ); |
6638 | ** </pre></blockquote>)^ |
6639 | ** |
6640 | ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg |
6641 | ** point to an appropriate error message (obtained from [sqlite3_mprintf()]) |
6642 | ** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg |
6643 | ** is NULL before calling the xEntryPoint(). ^SQLite will invoke |
6644 | ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any |
6645 | ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()], |
6646 | ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail. |
6647 | ** |
6648 | ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already |
6649 | ** on the list of automatic extensions is a harmless no-op. ^No entry point |
6650 | ** will be called more than once for each database connection that is opened. |
6651 | ** |
6652 | ** See also: [sqlite3_reset_auto_extension()] |
6653 | ** and [sqlite3_cancel_auto_extension()] |
6654 | */ |
6655 | SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void)); |
6656 | |
6657 | /* |
6658 | ** CAPI3REF: Cancel Automatic Extension Loading |
6659 | ** |
6660 | ** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the |
6661 | ** initialization routine X that was registered using a prior call to |
6662 | ** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)] |
6663 | ** routine returns 1 if initialization routine X was successfully |
6664 | ** unregistered and it returns 0 if X was not on the list of initialization |
6665 | ** routines. |
6666 | */ |
6667 | SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void)); |
6668 | |
6669 | /* |
6670 | ** CAPI3REF: Reset Automatic Extension Loading |
6671 | ** |
6672 | ** ^This interface disables all automatic extensions previously |
6673 | ** registered using [sqlite3_auto_extension()]. |
6674 | */ |
6675 | SQLITE_API void sqlite3_reset_auto_extension(void); |
6676 | |
6677 | /* |
6678 | ** The interface to the virtual-table mechanism is currently considered |
6679 | ** to be experimental. The interface might change in incompatible ways. |
6680 | ** If this is a problem for you, do not use the interface at this time. |
6681 | ** |
6682 | ** When the virtual-table mechanism stabilizes, we will declare the |
6683 | ** interface fixed, support it indefinitely, and remove this comment. |
6684 | */ |
6685 | |
6686 | /* |
6687 | ** Structures used by the virtual table interface |
6688 | */ |
6689 | typedef struct sqlite3_vtab sqlite3_vtab; |
6690 | typedef struct sqlite3_index_info sqlite3_index_info; |
6691 | typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; |
6692 | typedef struct sqlite3_module sqlite3_module; |
6693 | |
6694 | /* |
6695 | ** CAPI3REF: Virtual Table Object |
6696 | ** KEYWORDS: sqlite3_module {virtual table module} |
6697 | ** |
6698 | ** This structure, sometimes called a "virtual table module", |
6699 | ** defines the implementation of a [virtual table]. |
6700 | ** This structure consists mostly of methods for the module. |
6701 | ** |
6702 | ** ^A virtual table module is created by filling in a persistent |
6703 | ** instance of this structure and passing a pointer to that instance |
6704 | ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. |
6705 | ** ^The registration remains valid until it is replaced by a different |
6706 | ** module or until the [database connection] closes. The content |
6707 | ** of this structure must not change while it is registered with |
6708 | ** any database connection. |
6709 | */ |
6710 | struct sqlite3_module { |
6711 | int iVersion; |
6712 | int (*xCreate)(sqlite3*, void *pAux, |
6713 | int argc, const char *const*argv, |
6714 | sqlite3_vtab **ppVTab, char**); |
6715 | int (*xConnect)(sqlite3*, void *pAux, |
6716 | int argc, const char *const*argv, |
6717 | sqlite3_vtab **ppVTab, char**); |
6718 | int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); |
6719 | int (*xDisconnect)(sqlite3_vtab *pVTab); |
6720 | int (*xDestroy)(sqlite3_vtab *pVTab); |
6721 | int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); |
6722 | int (*xClose)(sqlite3_vtab_cursor*); |
6723 | int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, |
6724 | int argc, sqlite3_value **argv); |
6725 | int (*xNext)(sqlite3_vtab_cursor*); |
6726 | int (*xEof)(sqlite3_vtab_cursor*); |
6727 | int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); |
6728 | int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); |
6729 | int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); |
6730 | int (*xBegin)(sqlite3_vtab *pVTab); |
6731 | int (*xSync)(sqlite3_vtab *pVTab); |
6732 | int (*xCommit)(sqlite3_vtab *pVTab); |
6733 | int (*xRollback)(sqlite3_vtab *pVTab); |
6734 | int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, |
6735 | void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), |
6736 | void **ppArg); |
6737 | int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); |
6738 | /* The methods above are in version 1 of the sqlite_module object. Those |
6739 | ** below are for version 2 and greater. */ |
6740 | int (*xSavepoint)(sqlite3_vtab *pVTab, int); |
6741 | int (*xRelease)(sqlite3_vtab *pVTab, int); |
6742 | int (*xRollbackTo)(sqlite3_vtab *pVTab, int); |
6743 | /* The methods above are in versions 1 and 2 of the sqlite_module object. |
6744 | ** Those below are for version 3 and greater. */ |
6745 | int (*xShadowName)(const char*); |
6746 | }; |
6747 | |
6748 | /* |
6749 | ** CAPI3REF: Virtual Table Indexing Information |
6750 | ** KEYWORDS: sqlite3_index_info |
6751 | ** |
6752 | ** The sqlite3_index_info structure and its substructures is used as part |
6753 | ** of the [virtual table] interface to |
6754 | ** pass information into and receive the reply from the [xBestIndex] |
6755 | ** method of a [virtual table module]. The fields under **Inputs** are the |
6756 | ** inputs to xBestIndex and are read-only. xBestIndex inserts its |
6757 | ** results into the **Outputs** fields. |
6758 | ** |
6759 | ** ^(The aConstraint[] array records WHERE clause constraints of the form: |
6760 | ** |
6761 | ** <blockquote>column OP expr</blockquote> |
6762 | ** |
6763 | ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is |
6764 | ** stored in aConstraint[].op using one of the |
6765 | ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^ |
6766 | ** ^(The index of the column is stored in |
6767 | ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the |
6768 | ** expr on the right-hand side can be evaluated (and thus the constraint |
6769 | ** is usable) and false if it cannot.)^ |
6770 | ** |
6771 | ** ^The optimizer automatically inverts terms of the form "expr OP column" |
6772 | ** and makes other simplifications to the WHERE clause in an attempt to |
6773 | ** get as many WHERE clause terms into the form shown above as possible. |
6774 | ** ^The aConstraint[] array only reports WHERE clause terms that are |
6775 | ** relevant to the particular virtual table being queried. |
6776 | ** |
6777 | ** ^Information about the ORDER BY clause is stored in aOrderBy[]. |
6778 | ** ^Each term of aOrderBy records a column of the ORDER BY clause. |
6779 | ** |
6780 | ** The colUsed field indicates which columns of the virtual table may be |
6781 | ** required by the current scan. Virtual table columns are numbered from |
6782 | ** zero in the order in which they appear within the CREATE TABLE statement |
6783 | ** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62), |
6784 | ** the corresponding bit is set within the colUsed mask if the column may be |
6785 | ** required by SQLite. If the table has at least 64 columns and any column |
6786 | ** to the right of the first 63 is required, then bit 63 of colUsed is also |
6787 | ** set. In other words, column iCol may be required if the expression |
6788 | ** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to |
6789 | ** non-zero. |
6790 | ** |
6791 | ** The [xBestIndex] method must fill aConstraintUsage[] with information |
6792 | ** about what parameters to pass to xFilter. ^If argvIndex>0 then |
6793 | ** the right-hand side of the corresponding aConstraint[] is evaluated |
6794 | ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit |
6795 | ** is true, then the constraint is assumed to be fully handled by the |
6796 | ** virtual table and might not be checked again by the byte code.)^ ^(The |
6797 | ** aConstraintUsage[].omit flag is an optimization hint. When the omit flag |
6798 | ** is left in its default setting of false, the constraint will always be |
6799 | ** checked separately in byte code. If the omit flag is change to true, then |
6800 | ** the constraint may or may not be checked in byte code. In other words, |
6801 | ** when the omit flag is true there is no guarantee that the constraint will |
6802 | ** not be checked again using byte code.)^ |
6803 | ** |
6804 | ** ^The idxNum and idxPtr values are recorded and passed into the |
6805 | ** [xFilter] method. |
6806 | ** ^[sqlite3_free()] is used to free idxPtr if and only if |
6807 | ** needToFreeIdxPtr is true. |
6808 | ** |
6809 | ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in |
6810 | ** the correct order to satisfy the ORDER BY clause so that no separate |
6811 | ** sorting step is required. |
6812 | ** |
6813 | ** ^The estimatedCost value is an estimate of the cost of a particular |
6814 | ** strategy. A cost of N indicates that the cost of the strategy is similar |
6815 | ** to a linear scan of an SQLite table with N rows. A cost of log(N) |
6816 | ** indicates that the expense of the operation is similar to that of a |
6817 | ** binary search on a unique indexed field of an SQLite table with N rows. |
6818 | ** |
6819 | ** ^The estimatedRows value is an estimate of the number of rows that |
6820 | ** will be returned by the strategy. |
6821 | ** |
6822 | ** The xBestIndex method may optionally populate the idxFlags field with a |
6823 | ** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag - |
6824 | ** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite |
6825 | ** assumes that the strategy may visit at most one row. |
6826 | ** |
6827 | ** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then |
6828 | ** SQLite also assumes that if a call to the xUpdate() method is made as |
6829 | ** part of the same statement to delete or update a virtual table row and the |
6830 | ** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback |
6831 | ** any database changes. In other words, if the xUpdate() returns |
6832 | ** SQLITE_CONSTRAINT, the database contents must be exactly as they were |
6833 | ** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not |
6834 | ** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by |
6835 | ** the xUpdate method are automatically rolled back by SQLite. |
6836 | ** |
6837 | ** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info |
6838 | ** structure for SQLite [version 3.8.2] ([dateof:3.8.2]). |
6839 | ** If a virtual table extension is |
6840 | ** used with an SQLite version earlier than 3.8.2, the results of attempting |
6841 | ** to read or write the estimatedRows field are undefined (but are likely |
6842 | ** to include crashing the application). The estimatedRows field should |
6843 | ** therefore only be used if [sqlite3_libversion_number()] returns a |
6844 | ** value greater than or equal to 3008002. Similarly, the idxFlags field |
6845 | ** was added for [version 3.9.0] ([dateof:3.9.0]). |
6846 | ** It may therefore only be used if |
6847 | ** sqlite3_libversion_number() returns a value greater than or equal to |
6848 | ** 3009000. |
6849 | */ |
6850 | struct sqlite3_index_info { |
6851 | /* Inputs */ |
6852 | int nConstraint; /* Number of entries in aConstraint */ |
6853 | struct sqlite3_index_constraint { |
6854 | int iColumn; /* Column constrained. -1 for ROWID */ |
6855 | unsigned char op; /* Constraint operator */ |
6856 | unsigned char usable; /* True if this constraint is usable */ |
6857 | int iTermOffset; /* Used internally - xBestIndex should ignore */ |
6858 | } *aConstraint; /* Table of WHERE clause constraints */ |
6859 | int nOrderBy; /* Number of terms in the ORDER BY clause */ |
6860 | struct sqlite3_index_orderby { |
6861 | int iColumn; /* Column number */ |
6862 | unsigned char desc; /* True for DESC. False for ASC. */ |
6863 | } *aOrderBy; /* The ORDER BY clause */ |
6864 | /* Outputs */ |
6865 | struct sqlite3_index_constraint_usage { |
6866 | int argvIndex; /* if >0, constraint is part of argv to xFilter */ |
6867 | unsigned char omit; /* Do not code a test for this constraint */ |
6868 | } *aConstraintUsage; |
6869 | int idxNum; /* Number used to identify the index */ |
6870 | char *idxStr; /* String, possibly obtained from sqlite3_malloc */ |
6871 | int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ |
6872 | int orderByConsumed; /* True if output is already ordered */ |
6873 | double estimatedCost; /* Estimated cost of using this index */ |
6874 | /* Fields below are only available in SQLite 3.8.2 and later */ |
6875 | sqlite3_int64 estimatedRows; /* Estimated number of rows returned */ |
6876 | /* Fields below are only available in SQLite 3.9.0 and later */ |
6877 | int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */ |
6878 | /* Fields below are only available in SQLite 3.10.0 and later */ |
6879 | sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */ |
6880 | }; |
6881 | |
6882 | /* |
6883 | ** CAPI3REF: Virtual Table Scan Flags |
6884 | ** |
6885 | ** Virtual table implementations are allowed to set the |
6886 | ** [sqlite3_index_info].idxFlags field to some combination of |
6887 | ** these bits. |
6888 | */ |
6889 | #define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */ |
6890 | |
6891 | /* |
6892 | ** CAPI3REF: Virtual Table Constraint Operator Codes |
6893 | ** |
6894 | ** These macros define the allowed values for the |
6895 | ** [sqlite3_index_info].aConstraint[].op field. Each value represents |
6896 | ** an operator that is part of a constraint term in the wHERE clause of |
6897 | ** a query that uses a [virtual table]. |
6898 | */ |
6899 | #define SQLITE_INDEX_CONSTRAINT_EQ 2 |
6900 | #define SQLITE_INDEX_CONSTRAINT_GT 4 |
6901 | #define SQLITE_INDEX_CONSTRAINT_LE 8 |
6902 | #define SQLITE_INDEX_CONSTRAINT_LT 16 |
6903 | #define SQLITE_INDEX_CONSTRAINT_GE 32 |
6904 | #define SQLITE_INDEX_CONSTRAINT_MATCH 64 |
6905 | #define SQLITE_INDEX_CONSTRAINT_LIKE 65 |
6906 | #define SQLITE_INDEX_CONSTRAINT_GLOB 66 |
6907 | #define SQLITE_INDEX_CONSTRAINT_REGEXP 67 |
6908 | #define SQLITE_INDEX_CONSTRAINT_NE 68 |
6909 | #define SQLITE_INDEX_CONSTRAINT_ISNOT 69 |
6910 | #define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70 |
6911 | #define SQLITE_INDEX_CONSTRAINT_ISNULL 71 |
6912 | #define SQLITE_INDEX_CONSTRAINT_IS 72 |
6913 | #define SQLITE_INDEX_CONSTRAINT_FUNCTION 150 |
6914 | |
6915 | /* |
6916 | ** CAPI3REF: Register A Virtual Table Implementation |
6917 | ** METHOD: sqlite3 |
6918 | ** |
6919 | ** ^These routines are used to register a new [virtual table module] name. |
6920 | ** ^Module names must be registered before |
6921 | ** creating a new [virtual table] using the module and before using a |
6922 | ** preexisting [virtual table] for the module. |
6923 | ** |
6924 | ** ^The module name is registered on the [database connection] specified |
6925 | ** by the first parameter. ^The name of the module is given by the |
6926 | ** second parameter. ^The third parameter is a pointer to |
6927 | ** the implementation of the [virtual table module]. ^The fourth |
6928 | ** parameter is an arbitrary client data pointer that is passed through |
6929 | ** into the [xCreate] and [xConnect] methods of the virtual table module |
6930 | ** when a new virtual table is be being created or reinitialized. |
6931 | ** |
6932 | ** ^The sqlite3_create_module_v2() interface has a fifth parameter which |
6933 | ** is a pointer to a destructor for the pClientData. ^SQLite will |
6934 | ** invoke the destructor function (if it is not NULL) when SQLite |
6935 | ** no longer needs the pClientData pointer. ^The destructor will also |
6936 | ** be invoked if the call to sqlite3_create_module_v2() fails. |
6937 | ** ^The sqlite3_create_module() |
6938 | ** interface is equivalent to sqlite3_create_module_v2() with a NULL |
6939 | ** destructor. |
6940 | ** |
6941 | ** ^If the third parameter (the pointer to the sqlite3_module object) is |
6942 | ** NULL then no new module is create and any existing modules with the |
6943 | ** same name are dropped. |
6944 | ** |
6945 | ** See also: [sqlite3_drop_modules()] |
6946 | */ |
6947 | SQLITE_API int sqlite3_create_module( |
6948 | sqlite3 *db, /* SQLite connection to register module with */ |
6949 | const char *zName, /* Name of the module */ |
6950 | const sqlite3_module *p, /* Methods for the module */ |
6951 | void *pClientData /* Client data for xCreate/xConnect */ |
6952 | ); |
6953 | SQLITE_API int sqlite3_create_module_v2( |
6954 | sqlite3 *db, /* SQLite connection to register module with */ |
6955 | const char *zName, /* Name of the module */ |
6956 | const sqlite3_module *p, /* Methods for the module */ |
6957 | void *pClientData, /* Client data for xCreate/xConnect */ |
6958 | void(*xDestroy)(void*) /* Module destructor function */ |
6959 | ); |
6960 | |
6961 | /* |
6962 | ** CAPI3REF: Remove Unnecessary Virtual Table Implementations |
6963 | ** METHOD: sqlite3 |
6964 | ** |
6965 | ** ^The sqlite3_drop_modules(D,L) interface removes all virtual |
6966 | ** table modules from database connection D except those named on list L. |
6967 | ** The L parameter must be either NULL or a pointer to an array of pointers |
6968 | ** to strings where the array is terminated by a single NULL pointer. |
6969 | ** ^If the L parameter is NULL, then all virtual table modules are removed. |
6970 | ** |
6971 | ** See also: [sqlite3_create_module()] |
6972 | */ |
6973 | SQLITE_API int sqlite3_drop_modules( |
6974 | sqlite3 *db, /* Remove modules from this connection */ |
6975 | const char **azKeep /* Except, do not remove the ones named here */ |
6976 | ); |
6977 | |
6978 | /* |
6979 | ** CAPI3REF: Virtual Table Instance Object |
6980 | ** KEYWORDS: sqlite3_vtab |
6981 | ** |
6982 | ** Every [virtual table module] implementation uses a subclass |
6983 | ** of this object to describe a particular instance |
6984 | ** of the [virtual table]. Each subclass will |
6985 | ** be tailored to the specific needs of the module implementation. |
6986 | ** The purpose of this superclass is to define certain fields that are |
6987 | ** common to all module implementations. |
6988 | ** |
6989 | ** ^Virtual tables methods can set an error message by assigning a |
6990 | ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should |
6991 | ** take care that any prior string is freed by a call to [sqlite3_free()] |
6992 | ** prior to assigning a new string to zErrMsg. ^After the error message |
6993 | ** is delivered up to the client application, the string will be automatically |
6994 | ** freed by sqlite3_free() and the zErrMsg field will be zeroed. |
6995 | */ |
6996 | struct sqlite3_vtab { |
6997 | const sqlite3_module *pModule; /* The module for this virtual table */ |
6998 | int nRef; /* Number of open cursors */ |
6999 | char *zErrMsg; /* Error message from sqlite3_mprintf() */ |
7000 | /* Virtual table implementations will typically add additional fields */ |
7001 | }; |
7002 | |
7003 | /* |
7004 | ** CAPI3REF: Virtual Table Cursor Object |
7005 | ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} |
7006 | ** |
7007 | ** Every [virtual table module] implementation uses a subclass of the |
7008 | ** following structure to describe cursors that point into the |
7009 | ** [virtual table] and are used |
7010 | ** to loop through the virtual table. Cursors are created using the |
7011 | ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed |
7012 | ** by the [sqlite3_module.xClose | xClose] method. Cursors are used |
7013 | ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods |
7014 | ** of the module. Each module implementation will define |
7015 | ** the content of a cursor structure to suit its own needs. |
7016 | ** |
7017 | ** This superclass exists in order to define fields of the cursor that |
7018 | ** are common to all implementations. |
7019 | */ |
7020 | struct sqlite3_vtab_cursor { |
7021 | sqlite3_vtab *pVtab; /* Virtual table of this cursor */ |
7022 | /* Virtual table implementations will typically add additional fields */ |
7023 | }; |
7024 | |
7025 | /* |
7026 | ** CAPI3REF: Declare The Schema Of A Virtual Table |
7027 | ** |
7028 | ** ^The [xCreate] and [xConnect] methods of a |
7029 | ** [virtual table module] call this interface |
7030 | ** to declare the format (the names and datatypes of the columns) of |
7031 | ** the virtual tables they implement. |
7032 | */ |
7033 | SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL); |
7034 | |
7035 | /* |
7036 | ** CAPI3REF: Overload A Function For A Virtual Table |
7037 | ** METHOD: sqlite3 |
7038 | ** |
7039 | ** ^(Virtual tables can provide alternative implementations of functions |
7040 | ** using the [xFindFunction] method of the [virtual table module]. |
7041 | ** But global versions of those functions |
7042 | ** must exist in order to be overloaded.)^ |
7043 | ** |
7044 | ** ^(This API makes sure a global version of a function with a particular |
7045 | ** name and number of parameters exists. If no such function exists |
7046 | ** before this API is called, a new function is created.)^ ^The implementation |
7047 | ** of the new function always causes an exception to be thrown. So |
7048 | ** the new function is not good for anything by itself. Its only |
7049 | ** purpose is to be a placeholder function that can be overloaded |
7050 | ** by a [virtual table]. |
7051 | */ |
7052 | SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); |
7053 | |
7054 | /* |
7055 | ** The interface to the virtual-table mechanism defined above (back up |
7056 | ** to a comment remarkably similar to this one) is currently considered |
7057 | ** to be experimental. The interface might change in incompatible ways. |
7058 | ** If this is a problem for you, do not use the interface at this time. |
7059 | ** |
7060 | ** When the virtual-table mechanism stabilizes, we will declare the |
7061 | ** interface fixed, support it indefinitely, and remove this comment. |
7062 | */ |
7063 | |
7064 | /* |
7065 | ** CAPI3REF: A Handle To An Open BLOB |
7066 | ** KEYWORDS: {BLOB handle} {BLOB handles} |
7067 | ** |
7068 | ** An instance of this object represents an open BLOB on which |
7069 | ** [sqlite3_blob_open | incremental BLOB I/O] can be performed. |
7070 | ** ^Objects of this type are created by [sqlite3_blob_open()] |
7071 | ** and destroyed by [sqlite3_blob_close()]. |
7072 | ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces |
7073 | ** can be used to read or write small subsections of the BLOB. |
7074 | ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. |
7075 | */ |
7076 | typedef struct sqlite3_blob sqlite3_blob; |
7077 | |
7078 | /* |
7079 | ** CAPI3REF: Open A BLOB For Incremental I/O |
7080 | ** METHOD: sqlite3 |
7081 | ** CONSTRUCTOR: sqlite3_blob |
7082 | ** |
7083 | ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located |
7084 | ** in row iRow, column zColumn, table zTable in database zDb; |
7085 | ** in other words, the same BLOB that would be selected by: |
7086 | ** |
7087 | ** <pre> |
7088 | ** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow; |
7089 | ** </pre>)^ |
7090 | ** |
7091 | ** ^(Parameter zDb is not the filename that contains the database, but |
7092 | ** rather the symbolic name of the database. For attached databases, this is |
7093 | ** the name that appears after the AS keyword in the [ATTACH] statement. |
7094 | ** For the main database file, the database name is "main". For TEMP |
7095 | ** tables, the database name is "temp".)^ |
7096 | ** |
7097 | ** ^If the flags parameter is non-zero, then the BLOB is opened for read |
7098 | ** and write access. ^If the flags parameter is zero, the BLOB is opened for |
7099 | ** read-only access. |
7100 | ** |
7101 | ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored |
7102 | ** in *ppBlob. Otherwise an [error code] is returned and, unless the error |
7103 | ** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided |
7104 | ** the API is not misused, it is always safe to call [sqlite3_blob_close()] |
7105 | ** on *ppBlob after this function it returns. |
7106 | ** |
7107 | ** This function fails with SQLITE_ERROR if any of the following are true: |
7108 | ** <ul> |
7109 | ** <li> ^(Database zDb does not exist)^, |
7110 | ** <li> ^(Table zTable does not exist within database zDb)^, |
7111 | ** <li> ^(Table zTable is a WITHOUT ROWID table)^, |
7112 | ** <li> ^(Column zColumn does not exist)^, |
7113 | ** <li> ^(Row iRow is not present in the table)^, |
7114 | ** <li> ^(The specified column of row iRow contains a value that is not |
7115 | ** a TEXT or BLOB value)^, |
7116 | ** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE |
7117 | ** constraint and the blob is being opened for read/write access)^, |
7118 | ** <li> ^([foreign key constraints | Foreign key constraints] are enabled, |
7119 | ** column zColumn is part of a [child key] definition and the blob is |
7120 | ** being opened for read/write access)^. |
7121 | ** </ul> |
7122 | ** |
7123 | ** ^Unless it returns SQLITE_MISUSE, this function sets the |
7124 | ** [database connection] error code and message accessible via |
7125 | ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. |
7126 | ** |
7127 | ** A BLOB referenced by sqlite3_blob_open() may be read using the |
7128 | ** [sqlite3_blob_read()] interface and modified by using |
7129 | ** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a |
7130 | ** different row of the same table using the [sqlite3_blob_reopen()] |
7131 | ** interface. However, the column, table, or database of a [BLOB handle] |
7132 | ** cannot be changed after the [BLOB handle] is opened. |
7133 | ** |
7134 | ** ^(If the row that a BLOB handle points to is modified by an |
7135 | ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects |
7136 | ** then the BLOB handle is marked as "expired". |
7137 | ** This is true if any column of the row is changed, even a column |
7138 | ** other than the one the BLOB handle is open on.)^ |
7139 | ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for |
7140 | ** an expired BLOB handle fail with a return code of [SQLITE_ABORT]. |
7141 | ** ^(Changes written into a BLOB prior to the BLOB expiring are not |
7142 | ** rolled back by the expiration of the BLOB. Such changes will eventually |
7143 | ** commit if the transaction continues to completion.)^ |
7144 | ** |
7145 | ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of |
7146 | ** the opened blob. ^The size of a blob may not be changed by this |
7147 | ** interface. Use the [UPDATE] SQL command to change the size of a |
7148 | ** blob. |
7149 | ** |
7150 | ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces |
7151 | ** and the built-in [zeroblob] SQL function may be used to create a |
7152 | ** zero-filled blob to read or write using the incremental-blob interface. |
7153 | ** |
7154 | ** To avoid a resource leak, every open [BLOB handle] should eventually |
7155 | ** be released by a call to [sqlite3_blob_close()]. |
7156 | ** |
7157 | ** See also: [sqlite3_blob_close()], |
7158 | ** [sqlite3_blob_reopen()], [sqlite3_blob_read()], |
7159 | ** [sqlite3_blob_bytes()], [sqlite3_blob_write()]. |
7160 | */ |
7161 | SQLITE_API int sqlite3_blob_open( |
7162 | sqlite3*, |
7163 | const char *zDb, |
7164 | const char *zTable, |
7165 | const char *zColumn, |
7166 | sqlite3_int64 iRow, |
7167 | int flags, |
7168 | sqlite3_blob **ppBlob |
7169 | ); |
7170 | |
7171 | /* |
7172 | ** CAPI3REF: Move a BLOB Handle to a New Row |
7173 | ** METHOD: sqlite3_blob |
7174 | ** |
7175 | ** ^This function is used to move an existing [BLOB handle] so that it points |
7176 | ** to a different row of the same database table. ^The new row is identified |
7177 | ** by the rowid value passed as the second argument. Only the row can be |
7178 | ** changed. ^The database, table and column on which the blob handle is open |
7179 | ** remain the same. Moving an existing [BLOB handle] to a new row is |
7180 | ** faster than closing the existing handle and opening a new one. |
7181 | ** |
7182 | ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] - |
7183 | ** it must exist and there must be either a blob or text value stored in |
7184 | ** the nominated column.)^ ^If the new row is not present in the table, or if |
7185 | ** it does not contain a blob or text value, or if another error occurs, an |
7186 | ** SQLite error code is returned and the blob handle is considered aborted. |
7187 | ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or |
7188 | ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return |
7189 | ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle |
7190 | ** always returns zero. |
7191 | ** |
7192 | ** ^This function sets the database handle error code and message. |
7193 | */ |
7194 | SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64); |
7195 | |
7196 | /* |
7197 | ** CAPI3REF: Close A BLOB Handle |
7198 | ** DESTRUCTOR: sqlite3_blob |
7199 | ** |
7200 | ** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed |
7201 | ** unconditionally. Even if this routine returns an error code, the |
7202 | ** handle is still closed.)^ |
7203 | ** |
7204 | ** ^If the blob handle being closed was opened for read-write access, and if |
7205 | ** the database is in auto-commit mode and there are no other open read-write |
7206 | ** blob handles or active write statements, the current transaction is |
7207 | ** committed. ^If an error occurs while committing the transaction, an error |
7208 | ** code is returned and the transaction rolled back. |
7209 | ** |
7210 | ** Calling this function with an argument that is not a NULL pointer or an |
7211 | ** open blob handle results in undefined behaviour. ^Calling this routine |
7212 | ** with a null pointer (such as would be returned by a failed call to |
7213 | ** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function |
7214 | ** is passed a valid open blob handle, the values returned by the |
7215 | ** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning. |
7216 | */ |
7217 | SQLITE_API int sqlite3_blob_close(sqlite3_blob *); |
7218 | |
7219 | /* |
7220 | ** CAPI3REF: Return The Size Of An Open BLOB |
7221 | ** METHOD: sqlite3_blob |
7222 | ** |
7223 | ** ^Returns the size in bytes of the BLOB accessible via the |
7224 | ** successfully opened [BLOB handle] in its only argument. ^The |
7225 | ** incremental blob I/O routines can only read or overwriting existing |
7226 | ** blob content; they cannot change the size of a blob. |
7227 | ** |
7228 | ** This routine only works on a [BLOB handle] which has been created |
7229 | ** by a prior successful call to [sqlite3_blob_open()] and which has not |
7230 | ** been closed by [sqlite3_blob_close()]. Passing any other pointer in |
7231 | ** to this routine results in undefined and probably undesirable behavior. |
7232 | */ |
7233 | SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *); |
7234 | |
7235 | /* |
7236 | ** CAPI3REF: Read Data From A BLOB Incrementally |
7237 | ** METHOD: sqlite3_blob |
7238 | ** |
7239 | ** ^(This function is used to read data from an open [BLOB handle] into a |
7240 | ** caller-supplied buffer. N bytes of data are copied into buffer Z |
7241 | ** from the open BLOB, starting at offset iOffset.)^ |
7242 | ** |
7243 | ** ^If offset iOffset is less than N bytes from the end of the BLOB, |
7244 | ** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is |
7245 | ** less than zero, [SQLITE_ERROR] is returned and no data is read. |
7246 | ** ^The size of the blob (and hence the maximum value of N+iOffset) |
7247 | ** can be determined using the [sqlite3_blob_bytes()] interface. |
7248 | ** |
7249 | ** ^An attempt to read from an expired [BLOB handle] fails with an |
7250 | ** error code of [SQLITE_ABORT]. |
7251 | ** |
7252 | ** ^(On success, sqlite3_blob_read() returns SQLITE_OK. |
7253 | ** Otherwise, an [error code] or an [extended error code] is returned.)^ |
7254 | ** |
7255 | ** This routine only works on a [BLOB handle] which has been created |
7256 | ** by a prior successful call to [sqlite3_blob_open()] and which has not |
7257 | ** been closed by [sqlite3_blob_close()]. Passing any other pointer in |
7258 | ** to this routine results in undefined and probably undesirable behavior. |
7259 | ** |
7260 | ** See also: [sqlite3_blob_write()]. |
7261 | */ |
7262 | SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); |
7263 | |
7264 | /* |
7265 | ** CAPI3REF: Write Data Into A BLOB Incrementally |
7266 | ** METHOD: sqlite3_blob |
7267 | ** |
7268 | ** ^(This function is used to write data into an open [BLOB handle] from a |
7269 | ** caller-supplied buffer. N bytes of data are copied from the buffer Z |
7270 | ** into the open BLOB, starting at offset iOffset.)^ |
7271 | ** |
7272 | ** ^(On success, sqlite3_blob_write() returns SQLITE_OK. |
7273 | ** Otherwise, an [error code] or an [extended error code] is returned.)^ |
7274 | ** ^Unless SQLITE_MISUSE is returned, this function sets the |
7275 | ** [database connection] error code and message accessible via |
7276 | ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. |
7277 | ** |
7278 | ** ^If the [BLOB handle] passed as the first argument was not opened for |
7279 | ** writing (the flags parameter to [sqlite3_blob_open()] was zero), |
7280 | ** this function returns [SQLITE_READONLY]. |
7281 | ** |
7282 | ** This function may only modify the contents of the BLOB; it is |
7283 | ** not possible to increase the size of a BLOB using this API. |
7284 | ** ^If offset iOffset is less than N bytes from the end of the BLOB, |
7285 | ** [SQLITE_ERROR] is returned and no data is written. The size of the |
7286 | ** BLOB (and hence the maximum value of N+iOffset) can be determined |
7287 | ** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less |
7288 | ** than zero [SQLITE_ERROR] is returned and no data is written. |
7289 | ** |
7290 | ** ^An attempt to write to an expired [BLOB handle] fails with an |
7291 | ** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred |
7292 | ** before the [BLOB handle] expired are not rolled back by the |
7293 | ** expiration of the handle, though of course those changes might |
7294 | ** have been overwritten by the statement that expired the BLOB handle |
7295 | ** or by other independent statements. |
7296 | ** |
7297 | ** This routine only works on a [BLOB handle] which has been created |
7298 | ** by a prior successful call to [sqlite3_blob_open()] and which has not |
7299 | ** been closed by [sqlite3_blob_close()]. Passing any other pointer in |
7300 | ** to this routine results in undefined and probably undesirable behavior. |
7301 | ** |
7302 | ** See also: [sqlite3_blob_read()]. |
7303 | */ |
7304 | SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); |
7305 | |
7306 | /* |
7307 | ** CAPI3REF: Virtual File System Objects |
7308 | ** |
7309 | ** A virtual filesystem (VFS) is an [sqlite3_vfs] object |
7310 | ** that SQLite uses to interact |
7311 | ** with the underlying operating system. Most SQLite builds come with a |
7312 | ** single default VFS that is appropriate for the host computer. |
7313 | ** New VFSes can be registered and existing VFSes can be unregistered. |
7314 | ** The following interfaces are provided. |
7315 | ** |
7316 | ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. |
7317 | ** ^Names are case sensitive. |
7318 | ** ^Names are zero-terminated UTF-8 strings. |
7319 | ** ^If there is no match, a NULL pointer is returned. |
7320 | ** ^If zVfsName is NULL then the default VFS is returned. |
7321 | ** |
7322 | ** ^New VFSes are registered with sqlite3_vfs_register(). |
7323 | ** ^Each new VFS becomes the default VFS if the makeDflt flag is set. |
7324 | ** ^The same VFS can be registered multiple times without injury. |
7325 | ** ^To make an existing VFS into the default VFS, register it again |
7326 | ** with the makeDflt flag set. If two different VFSes with the |
7327 | ** same name are registered, the behavior is undefined. If a |
7328 | ** VFS is registered with a name that is NULL or an empty string, |
7329 | ** then the behavior is undefined. |
7330 | ** |
7331 | ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface. |
7332 | ** ^(If the default VFS is unregistered, another VFS is chosen as |
7333 | ** the default. The choice for the new VFS is arbitrary.)^ |
7334 | */ |
7335 | SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); |
7336 | SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); |
7337 | SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*); |
7338 | |
7339 | /* |
7340 | ** CAPI3REF: Mutexes |
7341 | ** |
7342 | ** The SQLite core uses these routines for thread |
7343 | ** synchronization. Though they are intended for internal |
7344 | ** use by SQLite, code that links against SQLite is |
7345 | ** permitted to use any of these routines. |
7346 | ** |
7347 | ** The SQLite source code contains multiple implementations |
7348 | ** of these mutex routines. An appropriate implementation |
7349 | ** is selected automatically at compile-time. The following |
7350 | ** implementations are available in the SQLite core: |
7351 | ** |
7352 | ** <ul> |
7353 | ** <li> SQLITE_MUTEX_PTHREADS |
7354 | ** <li> SQLITE_MUTEX_W32 |
7355 | ** <li> SQLITE_MUTEX_NOOP |
7356 | ** </ul> |
7357 | ** |
7358 | ** The SQLITE_MUTEX_NOOP implementation is a set of routines |
7359 | ** that does no real locking and is appropriate for use in |
7360 | ** a single-threaded application. The SQLITE_MUTEX_PTHREADS and |
7361 | ** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix |
7362 | ** and Windows. |
7363 | ** |
7364 | ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor |
7365 | ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex |
7366 | ** implementation is included with the library. In this case the |
7367 | ** application must supply a custom mutex implementation using the |
7368 | ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function |
7369 | ** before calling sqlite3_initialize() or any other public sqlite3_ |
7370 | ** function that calls sqlite3_initialize(). |
7371 | ** |
7372 | ** ^The sqlite3_mutex_alloc() routine allocates a new |
7373 | ** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc() |
7374 | ** routine returns NULL if it is unable to allocate the requested |
7375 | ** mutex. The argument to sqlite3_mutex_alloc() must one of these |
7376 | ** integer constants: |
7377 | ** |
7378 | ** <ul> |
7379 | ** <li> SQLITE_MUTEX_FAST |
7380 | ** <li> SQLITE_MUTEX_RECURSIVE |
7381 | ** <li> SQLITE_MUTEX_STATIC_MAIN |
7382 | ** <li> SQLITE_MUTEX_STATIC_MEM |
7383 | ** <li> SQLITE_MUTEX_STATIC_OPEN |
7384 | ** <li> SQLITE_MUTEX_STATIC_PRNG |
7385 | ** <li> SQLITE_MUTEX_STATIC_LRU |
7386 | ** <li> SQLITE_MUTEX_STATIC_PMEM |
7387 | ** <li> SQLITE_MUTEX_STATIC_APP1 |
7388 | ** <li> SQLITE_MUTEX_STATIC_APP2 |
7389 | ** <li> SQLITE_MUTEX_STATIC_APP3 |
7390 | ** <li> SQLITE_MUTEX_STATIC_VFS1 |
7391 | ** <li> SQLITE_MUTEX_STATIC_VFS2 |
7392 | ** <li> SQLITE_MUTEX_STATIC_VFS3 |
7393 | ** </ul> |
7394 | ** |
7395 | ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) |
7396 | ** cause sqlite3_mutex_alloc() to create |
7397 | ** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE |
7398 | ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. |
7399 | ** The mutex implementation does not need to make a distinction |
7400 | ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does |
7401 | ** not want to. SQLite will only request a recursive mutex in |
7402 | ** cases where it really needs one. If a faster non-recursive mutex |
7403 | ** implementation is available on the host platform, the mutex subsystem |
7404 | ** might return such a mutex in response to SQLITE_MUTEX_FAST. |
7405 | ** |
7406 | ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other |
7407 | ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return |
7408 | ** a pointer to a static preexisting mutex. ^Nine static mutexes are |
7409 | ** used by the current version of SQLite. Future versions of SQLite |
7410 | ** may add additional static mutexes. Static mutexes are for internal |
7411 | ** use by SQLite only. Applications that use SQLite mutexes should |
7412 | ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or |
7413 | ** SQLITE_MUTEX_RECURSIVE. |
7414 | ** |
7415 | ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST |
7416 | ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() |
7417 | ** returns a different mutex on every call. ^For the static |
7418 | ** mutex types, the same mutex is returned on every call that has |
7419 | ** the same type number. |
7420 | ** |
7421 | ** ^The sqlite3_mutex_free() routine deallocates a previously |
7422 | ** allocated dynamic mutex. Attempting to deallocate a static |
7423 | ** mutex results in undefined behavior. |
7424 | ** |
7425 | ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt |
7426 | ** to enter a mutex. ^If another thread is already within the mutex, |
7427 | ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return |
7428 | ** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK] |
7429 | ** upon successful entry. ^(Mutexes created using |
7430 | ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. |
7431 | ** In such cases, the |
7432 | ** mutex must be exited an equal number of times before another thread |
7433 | ** can enter.)^ If the same thread tries to enter any mutex other |
7434 | ** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined. |
7435 | ** |
7436 | ** ^(Some systems (for example, Windows 95) do not support the operation |
7437 | ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() |
7438 | ** will always return SQLITE_BUSY. The SQLite core only ever uses |
7439 | ** sqlite3_mutex_try() as an optimization so this is acceptable |
7440 | ** behavior.)^ |
7441 | ** |
7442 | ** ^The sqlite3_mutex_leave() routine exits a mutex that was |
7443 | ** previously entered by the same thread. The behavior |
7444 | ** is undefined if the mutex is not currently entered by the |
7445 | ** calling thread or is not currently allocated. |
7446 | ** |
7447 | ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or |
7448 | ** sqlite3_mutex_leave() is a NULL pointer, then all three routines |
7449 | ** behave as no-ops. |
7450 | ** |
7451 | ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. |
7452 | */ |
7453 | SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int); |
7454 | SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*); |
7455 | SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*); |
7456 | SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*); |
7457 | SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*); |
7458 | |
7459 | /* |
7460 | ** CAPI3REF: Mutex Methods Object |
7461 | ** |
7462 | ** An instance of this structure defines the low-level routines |
7463 | ** used to allocate and use mutexes. |
7464 | ** |
7465 | ** Usually, the default mutex implementations provided by SQLite are |
7466 | ** sufficient, however the application has the option of substituting a custom |
7467 | ** implementation for specialized deployments or systems for which SQLite |
7468 | ** does not provide a suitable implementation. In this case, the application |
7469 | ** creates and populates an instance of this structure to pass |
7470 | ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. |
7471 | ** Additionally, an instance of this structure can be used as an |
7472 | ** output variable when querying the system for the current mutex |
7473 | ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. |
7474 | ** |
7475 | ** ^The xMutexInit method defined by this structure is invoked as |
7476 | ** part of system initialization by the sqlite3_initialize() function. |
7477 | ** ^The xMutexInit routine is called by SQLite exactly once for each |
7478 | ** effective call to [sqlite3_initialize()]. |
7479 | ** |
7480 | ** ^The xMutexEnd method defined by this structure is invoked as |
7481 | ** part of system shutdown by the sqlite3_shutdown() function. The |
7482 | ** implementation of this method is expected to release all outstanding |
7483 | ** resources obtained by the mutex methods implementation, especially |
7484 | ** those obtained by the xMutexInit method. ^The xMutexEnd() |
7485 | ** interface is invoked exactly once for each call to [sqlite3_shutdown()]. |
7486 | ** |
7487 | ** ^(The remaining seven methods defined by this structure (xMutexAlloc, |
7488 | ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and |
7489 | ** xMutexNotheld) implement the following interfaces (respectively): |
7490 | ** |
7491 | ** <ul> |
7492 | ** <li> [sqlite3_mutex_alloc()] </li> |
7493 | ** <li> [sqlite3_mutex_free()] </li> |
7494 | ** <li> [sqlite3_mutex_enter()] </li> |
7495 | ** <li> [sqlite3_mutex_try()] </li> |
7496 | ** <li> [sqlite3_mutex_leave()] </li> |
7497 | ** <li> [sqlite3_mutex_held()] </li> |
7498 | ** <li> [sqlite3_mutex_notheld()] </li> |
7499 | ** </ul>)^ |
7500 | ** |
7501 | ** The only difference is that the public sqlite3_XXX functions enumerated |
7502 | ** above silently ignore any invocations that pass a NULL pointer instead |
7503 | ** of a valid mutex handle. The implementations of the methods defined |
7504 | ** by this structure are not required to handle this case. The results |
7505 | ** of passing a NULL pointer instead of a valid mutex handle are undefined |
7506 | ** (i.e. it is acceptable to provide an implementation that segfaults if |
7507 | ** it is passed a NULL pointer). |
7508 | ** |
7509 | ** The xMutexInit() method must be threadsafe. It must be harmless to |
7510 | ** invoke xMutexInit() multiple times within the same process and without |
7511 | ** intervening calls to xMutexEnd(). Second and subsequent calls to |
7512 | ** xMutexInit() must be no-ops. |
7513 | ** |
7514 | ** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] |
7515 | ** and its associates). Similarly, xMutexAlloc() must not use SQLite memory |
7516 | ** allocation for a static mutex. ^However xMutexAlloc() may use SQLite |
7517 | ** memory allocation for a fast or recursive mutex. |
7518 | ** |
7519 | ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is |
7520 | ** called, but only if the prior call to xMutexInit returned SQLITE_OK. |
7521 | ** If xMutexInit fails in any way, it is expected to clean up after itself |
7522 | ** prior to returning. |
7523 | */ |
7524 | typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; |
7525 | struct sqlite3_mutex_methods { |
7526 | int (*xMutexInit)(void); |
7527 | int (*xMutexEnd)(void); |
7528 | sqlite3_mutex *(*xMutexAlloc)(int); |
7529 | void (*xMutexFree)(sqlite3_mutex *); |
7530 | void (*xMutexEnter)(sqlite3_mutex *); |
7531 | int (*xMutexTry)(sqlite3_mutex *); |
7532 | void (*xMutexLeave)(sqlite3_mutex *); |
7533 | int (*xMutexHeld)(sqlite3_mutex *); |
7534 | int (*xMutexNotheld)(sqlite3_mutex *); |
7535 | }; |
7536 | |
7537 | /* |
7538 | ** CAPI3REF: Mutex Verification Routines |
7539 | ** |
7540 | ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines |
7541 | ** are intended for use inside assert() statements. The SQLite core |
7542 | ** never uses these routines except inside an assert() and applications |
7543 | ** are advised to follow the lead of the core. The SQLite core only |
7544 | ** provides implementations for these routines when it is compiled |
7545 | ** with the SQLITE_DEBUG flag. External mutex implementations |
7546 | ** are only required to provide these routines if SQLITE_DEBUG is |
7547 | ** defined and if NDEBUG is not defined. |
7548 | ** |
7549 | ** These routines should return true if the mutex in their argument |
7550 | ** is held or not held, respectively, by the calling thread. |
7551 | ** |
7552 | ** The implementation is not required to provide versions of these |
7553 | ** routines that actually work. If the implementation does not provide working |
7554 | ** versions of these routines, it should at least provide stubs that always |
7555 | ** return true so that one does not get spurious assertion failures. |
7556 | ** |
7557 | ** If the argument to sqlite3_mutex_held() is a NULL pointer then |
7558 | ** the routine should return 1. This seems counter-intuitive since |
7559 | ** clearly the mutex cannot be held if it does not exist. But |
7560 | ** the reason the mutex does not exist is because the build is not |
7561 | ** using mutexes. And we do not want the assert() containing the |
7562 | ** call to sqlite3_mutex_held() to fail, so a non-zero return is |
7563 | ** the appropriate thing to do. The sqlite3_mutex_notheld() |
7564 | ** interface should also return 1 when given a NULL pointer. |
7565 | */ |
7566 | #ifndef NDEBUG |
7567 | SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*); |
7568 | SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*); |
7569 | #endif |
7570 | |
7571 | /* |
7572 | ** CAPI3REF: Mutex Types |
7573 | ** |
7574 | ** The [sqlite3_mutex_alloc()] interface takes a single argument |
7575 | ** which is one of these integer constants. |
7576 | ** |
7577 | ** The set of static mutexes may change from one SQLite release to the |
7578 | ** next. Applications that override the built-in mutex logic must be |
7579 | ** prepared to accommodate additional static mutexes. |
7580 | */ |
7581 | #define SQLITE_MUTEX_FAST 0 |
7582 | #define SQLITE_MUTEX_RECURSIVE 1 |
7583 | #define SQLITE_MUTEX_STATIC_MAIN 2 |
7584 | #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ |
7585 | #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ |
7586 | #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ |
7587 | #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */ |
7588 | #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ |
7589 | #define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */ |
7590 | #define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */ |
7591 | #define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */ |
7592 | #define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */ |
7593 | #define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */ |
7594 | #define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */ |
7595 | #define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */ |
7596 | #define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */ |
7597 | |
7598 | /* Legacy compatibility: */ |
7599 | #define SQLITE_MUTEX_STATIC_MASTER 2 |
7600 | |
7601 | |
7602 | /* |
7603 | ** CAPI3REF: Retrieve the mutex for a database connection |
7604 | ** METHOD: sqlite3 |
7605 | ** |
7606 | ** ^This interface returns a pointer the [sqlite3_mutex] object that |
7607 | ** serializes access to the [database connection] given in the argument |
7608 | ** when the [threading mode] is Serialized. |
7609 | ** ^If the [threading mode] is Single-thread or Multi-thread then this |
7610 | ** routine returns a NULL pointer. |
7611 | */ |
7612 | SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*); |
7613 | |
7614 | /* |
7615 | ** CAPI3REF: Low-Level Control Of Database Files |
7616 | ** METHOD: sqlite3 |
7617 | ** KEYWORDS: {file control} |
7618 | ** |
7619 | ** ^The [sqlite3_file_control()] interface makes a direct call to the |
7620 | ** xFileControl method for the [sqlite3_io_methods] object associated |
7621 | ** with a particular database identified by the second argument. ^The |
7622 | ** name of the database is "main" for the main database or "temp" for the |
7623 | ** TEMP database, or the name that appears after the AS keyword for |
7624 | ** databases that are added using the [ATTACH] SQL command. |
7625 | ** ^A NULL pointer can be used in place of "main" to refer to the |
7626 | ** main database file. |
7627 | ** ^The third and fourth parameters to this routine |
7628 | ** are passed directly through to the second and third parameters of |
7629 | ** the xFileControl method. ^The return value of the xFileControl |
7630 | ** method becomes the return value of this routine. |
7631 | ** |
7632 | ** A few opcodes for [sqlite3_file_control()] are handled directly |
7633 | ** by the SQLite core and never invoke the |
7634 | ** sqlite3_io_methods.xFileControl method. |
7635 | ** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes |
7636 | ** a pointer to the underlying [sqlite3_file] object to be written into |
7637 | ** the space pointed to by the 4th parameter. The |
7638 | ** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns |
7639 | ** the [sqlite3_file] object associated with the journal file instead of |
7640 | ** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns |
7641 | ** a pointer to the underlying [sqlite3_vfs] object for the file. |
7642 | ** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter |
7643 | ** from the pager. |
7644 | ** |
7645 | ** ^If the second parameter (zDbName) does not match the name of any |
7646 | ** open database file, then SQLITE_ERROR is returned. ^This error |
7647 | ** code is not remembered and will not be recalled by [sqlite3_errcode()] |
7648 | ** or [sqlite3_errmsg()]. The underlying xFileControl method might |
7649 | ** also return SQLITE_ERROR. There is no way to distinguish between |
7650 | ** an incorrect zDbName and an SQLITE_ERROR return from the underlying |
7651 | ** xFileControl method. |
7652 | ** |
7653 | ** See also: [file control opcodes] |
7654 | */ |
7655 | SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); |
7656 | |
7657 | /* |
7658 | ** CAPI3REF: Testing Interface |
7659 | ** |
7660 | ** ^The sqlite3_test_control() interface is used to read out internal |
7661 | ** state of SQLite and to inject faults into SQLite for testing |
7662 | ** purposes. ^The first parameter is an operation code that determines |
7663 | ** the number, meaning, and operation of all subsequent parameters. |
7664 | ** |
7665 | ** This interface is not for use by applications. It exists solely |
7666 | ** for verifying the correct operation of the SQLite library. Depending |
7667 | ** on how the SQLite library is compiled, this interface might not exist. |
7668 | ** |
7669 | ** The details of the operation codes, their meanings, the parameters |
7670 | ** they take, and what they do are all subject to change without notice. |
7671 | ** Unlike most of the SQLite API, this function is not guaranteed to |
7672 | ** operate consistently from one release to the next. |
7673 | */ |
7674 | SQLITE_API int sqlite3_test_control(int op, ...); |
7675 | |
7676 | /* |
7677 | ** CAPI3REF: Testing Interface Operation Codes |
7678 | ** |
7679 | ** These constants are the valid operation code parameters used |
7680 | ** as the first argument to [sqlite3_test_control()]. |
7681 | ** |
7682 | ** These parameters and their meanings are subject to change |
7683 | ** without notice. These values are for testing purposes only. |
7684 | ** Applications should not use any of these parameters or the |
7685 | ** [sqlite3_test_control()] interface. |
7686 | */ |
7687 | #define SQLITE_TESTCTRL_FIRST 5 |
7688 | #define SQLITE_TESTCTRL_PRNG_SAVE 5 |
7689 | #define SQLITE_TESTCTRL_PRNG_RESTORE 6 |
7690 | #define SQLITE_TESTCTRL_PRNG_RESET 7 /* NOT USED */ |
7691 | #define SQLITE_TESTCTRL_BITVEC_TEST 8 |
7692 | #define SQLITE_TESTCTRL_FAULT_INSTALL 9 |
7693 | #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 |
7694 | #define SQLITE_TESTCTRL_PENDING_BYTE 11 |
7695 | #define SQLITE_TESTCTRL_ASSERT 12 |
7696 | #define SQLITE_TESTCTRL_ALWAYS 13 |
7697 | #define SQLITE_TESTCTRL_RESERVE 14 /* NOT USED */ |
7698 | #define SQLITE_TESTCTRL_OPTIMIZATIONS 15 |
7699 | #define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */ |
7700 | #define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */ |
7701 | #define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS 17 |
7702 | #define SQLITE_TESTCTRL_LOCALTIME_FAULT 18 |
7703 | #define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */ |
7704 | #define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19 |
7705 | #define SQLITE_TESTCTRL_NEVER_CORRUPT 20 |
7706 | #define SQLITE_TESTCTRL_VDBE_COVERAGE 21 |
7707 | #define SQLITE_TESTCTRL_BYTEORDER 22 |
7708 | #define SQLITE_TESTCTRL_ISINIT 23 |
7709 | #define SQLITE_TESTCTRL_SORTER_MMAP 24 |
7710 | #define SQLITE_TESTCTRL_IMPOSTER 25 |
7711 | #define SQLITE_TESTCTRL_PARSER_COVERAGE 26 |
7712 | #define SQLITE_TESTCTRL_RESULT_INTREAL 27 |
7713 | #define SQLITE_TESTCTRL_PRNG_SEED 28 |
7714 | #define 29 |
7715 | #define SQLITE_TESTCTRL_LAST 29 /* Largest TESTCTRL */ |
7716 | |
7717 | /* |
7718 | ** CAPI3REF: SQL Keyword Checking |
7719 | ** |
7720 | ** These routines provide access to the set of SQL language keywords |
7721 | ** recognized by SQLite. Applications can uses these routines to determine |
7722 | ** whether or not a specific identifier needs to be escaped (for example, |
7723 | ** by enclosing in double-quotes) so as not to confuse the parser. |
7724 | ** |
7725 | ** The sqlite3_keyword_count() interface returns the number of distinct |
7726 | ** keywords understood by SQLite. |
7727 | ** |
7728 | ** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and |
7729 | ** makes *Z point to that keyword expressed as UTF8 and writes the number |
7730 | ** of bytes in the keyword into *L. The string that *Z points to is not |
7731 | ** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns |
7732 | ** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z |
7733 | ** or L are NULL or invalid pointers then calls to |
7734 | ** sqlite3_keyword_name(N,Z,L) result in undefined behavior. |
7735 | ** |
7736 | ** The sqlite3_keyword_check(Z,L) interface checks to see whether or not |
7737 | ** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero |
7738 | ** if it is and zero if not. |
7739 | ** |
7740 | ** The parser used by SQLite is forgiving. It is often possible to use |
7741 | ** a keyword as an identifier as long as such use does not result in a |
7742 | ** parsing ambiguity. For example, the statement |
7743 | ** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and |
7744 | ** creates a new table named "BEGIN" with three columns named |
7745 | ** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid |
7746 | ** using keywords as identifiers. Common techniques used to avoid keyword |
7747 | ** name collisions include: |
7748 | ** <ul> |
7749 | ** <li> Put all identifier names inside double-quotes. This is the official |
7750 | ** SQL way to escape identifier names. |
7751 | ** <li> Put identifier names inside [...]. This is not standard SQL, |
7752 | ** but it is what SQL Server does and so lots of programmers use this |
7753 | ** technique. |
7754 | ** <li> Begin every identifier with the letter "Z" as no SQL keywords start |
7755 | ** with "Z". |
7756 | ** <li> Include a digit somewhere in every identifier name. |
7757 | ** </ul> |
7758 | ** |
7759 | ** Note that the number of keywords understood by SQLite can depend on |
7760 | ** compile-time options. For example, "VACUUM" is not a keyword if |
7761 | ** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also, |
7762 | ** new keywords may be added to future releases of SQLite. |
7763 | */ |
7764 | SQLITE_API int sqlite3_keyword_count(void); |
7765 | SQLITE_API int sqlite3_keyword_name(int,const char**,int*); |
7766 | SQLITE_API int sqlite3_keyword_check(const char*,int); |
7767 | |
7768 | /* |
7769 | ** CAPI3REF: Dynamic String Object |
7770 | ** KEYWORDS: {dynamic string} |
7771 | ** |
7772 | ** An instance of the sqlite3_str object contains a dynamically-sized |
7773 | ** string under construction. |
7774 | ** |
7775 | ** The lifecycle of an sqlite3_str object is as follows: |
7776 | ** <ol> |
7777 | ** <li> ^The sqlite3_str object is created using [sqlite3_str_new()]. |
7778 | ** <li> ^Text is appended to the sqlite3_str object using various |
7779 | ** methods, such as [sqlite3_str_appendf()]. |
7780 | ** <li> ^The sqlite3_str object is destroyed and the string it created |
7781 | ** is returned using the [sqlite3_str_finish()] interface. |
7782 | ** </ol> |
7783 | */ |
7784 | typedef struct sqlite3_str sqlite3_str; |
7785 | |
7786 | /* |
7787 | ** CAPI3REF: Create A New Dynamic String Object |
7788 | ** CONSTRUCTOR: sqlite3_str |
7789 | ** |
7790 | ** ^The [sqlite3_str_new(D)] interface allocates and initializes |
7791 | ** a new [sqlite3_str] object. To avoid memory leaks, the object returned by |
7792 | ** [sqlite3_str_new()] must be freed by a subsequent call to |
7793 | ** [sqlite3_str_finish(X)]. |
7794 | ** |
7795 | ** ^The [sqlite3_str_new(D)] interface always returns a pointer to a |
7796 | ** valid [sqlite3_str] object, though in the event of an out-of-memory |
7797 | ** error the returned object might be a special singleton that will |
7798 | ** silently reject new text, always return SQLITE_NOMEM from |
7799 | ** [sqlite3_str_errcode()], always return 0 for |
7800 | ** [sqlite3_str_length()], and always return NULL from |
7801 | ** [sqlite3_str_finish(X)]. It is always safe to use the value |
7802 | ** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter |
7803 | ** to any of the other [sqlite3_str] methods. |
7804 | ** |
7805 | ** The D parameter to [sqlite3_str_new(D)] may be NULL. If the |
7806 | ** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum |
7807 | ** length of the string contained in the [sqlite3_str] object will be |
7808 | ** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead |
7809 | ** of [SQLITE_MAX_LENGTH]. |
7810 | */ |
7811 | SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*); |
7812 | |
7813 | /* |
7814 | ** CAPI3REF: Finalize A Dynamic String |
7815 | ** DESTRUCTOR: sqlite3_str |
7816 | ** |
7817 | ** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X |
7818 | ** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()] |
7819 | ** that contains the constructed string. The calling application should |
7820 | ** pass the returned value to [sqlite3_free()] to avoid a memory leak. |
7821 | ** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any |
7822 | ** errors were encountered during construction of the string. ^The |
7823 | ** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the |
7824 | ** string in [sqlite3_str] object X is zero bytes long. |
7825 | */ |
7826 | SQLITE_API char *sqlite3_str_finish(sqlite3_str*); |
7827 | |
7828 | /* |
7829 | ** CAPI3REF: Add Content To A Dynamic String |
7830 | ** METHOD: sqlite3_str |
7831 | ** |
7832 | ** These interfaces add content to an sqlite3_str object previously obtained |
7833 | ** from [sqlite3_str_new()]. |
7834 | ** |
7835 | ** ^The [sqlite3_str_appendf(X,F,...)] and |
7836 | ** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf] |
7837 | ** functionality of SQLite to append formatted text onto the end of |
7838 | ** [sqlite3_str] object X. |
7839 | ** |
7840 | ** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S |
7841 | ** onto the end of the [sqlite3_str] object X. N must be non-negative. |
7842 | ** S must contain at least N non-zero bytes of content. To append a |
7843 | ** zero-terminated string in its entirety, use the [sqlite3_str_appendall()] |
7844 | ** method instead. |
7845 | ** |
7846 | ** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of |
7847 | ** zero-terminated string S onto the end of [sqlite3_str] object X. |
7848 | ** |
7849 | ** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the |
7850 | ** single-byte character C onto the end of [sqlite3_str] object X. |
7851 | ** ^This method can be used, for example, to add whitespace indentation. |
7852 | ** |
7853 | ** ^The [sqlite3_str_reset(X)] method resets the string under construction |
7854 | ** inside [sqlite3_str] object X back to zero bytes in length. |
7855 | ** |
7856 | ** These methods do not return a result code. ^If an error occurs, that fact |
7857 | ** is recorded in the [sqlite3_str] object and can be recovered by a |
7858 | ** subsequent call to [sqlite3_str_errcode(X)]. |
7859 | */ |
7860 | SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...); |
7861 | SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list); |
7862 | SQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N); |
7863 | SQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn); |
7864 | SQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C); |
7865 | SQLITE_API void sqlite3_str_reset(sqlite3_str*); |
7866 | |
7867 | /* |
7868 | ** CAPI3REF: Status Of A Dynamic String |
7869 | ** METHOD: sqlite3_str |
7870 | ** |
7871 | ** These interfaces return the current status of an [sqlite3_str] object. |
7872 | ** |
7873 | ** ^If any prior errors have occurred while constructing the dynamic string |
7874 | ** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return |
7875 | ** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns |
7876 | ** [SQLITE_NOMEM] following any out-of-memory error, or |
7877 | ** [SQLITE_TOOBIG] if the size of the dynamic string exceeds |
7878 | ** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors. |
7879 | ** |
7880 | ** ^The [sqlite3_str_length(X)] method returns the current length, in bytes, |
7881 | ** of the dynamic string under construction in [sqlite3_str] object X. |
7882 | ** ^The length returned by [sqlite3_str_length(X)] does not include the |
7883 | ** zero-termination byte. |
7884 | ** |
7885 | ** ^The [sqlite3_str_value(X)] method returns a pointer to the current |
7886 | ** content of the dynamic string under construction in X. The value |
7887 | ** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X |
7888 | ** and might be freed or altered by any subsequent method on the same |
7889 | ** [sqlite3_str] object. Applications must not used the pointer returned |
7890 | ** [sqlite3_str_value(X)] after any subsequent method call on the same |
7891 | ** object. ^Applications may change the content of the string returned |
7892 | ** by [sqlite3_str_value(X)] as long as they do not write into any bytes |
7893 | ** outside the range of 0 to [sqlite3_str_length(X)] and do not read or |
7894 | ** write any byte after any subsequent sqlite3_str method call. |
7895 | */ |
7896 | SQLITE_API int sqlite3_str_errcode(sqlite3_str*); |
7897 | SQLITE_API int sqlite3_str_length(sqlite3_str*); |
7898 | SQLITE_API char *sqlite3_str_value(sqlite3_str*); |
7899 | |
7900 | /* |
7901 | ** CAPI3REF: SQLite Runtime Status |
7902 | ** |
7903 | ** ^These interfaces are used to retrieve runtime status information |
7904 | ** about the performance of SQLite, and optionally to reset various |
7905 | ** highwater marks. ^The first argument is an integer code for |
7906 | ** the specific parameter to measure. ^(Recognized integer codes |
7907 | ** are of the form [status parameters | SQLITE_STATUS_...].)^ |
7908 | ** ^The current value of the parameter is returned into *pCurrent. |
7909 | ** ^The highest recorded value is returned in *pHighwater. ^If the |
7910 | ** resetFlag is true, then the highest record value is reset after |
7911 | ** *pHighwater is written. ^(Some parameters do not record the highest |
7912 | ** value. For those parameters |
7913 | ** nothing is written into *pHighwater and the resetFlag is ignored.)^ |
7914 | ** ^(Other parameters record only the highwater mark and not the current |
7915 | ** value. For these latter parameters nothing is written into *pCurrent.)^ |
7916 | ** |
7917 | ** ^The sqlite3_status() and sqlite3_status64() routines return |
7918 | ** SQLITE_OK on success and a non-zero [error code] on failure. |
7919 | ** |
7920 | ** If either the current value or the highwater mark is too large to |
7921 | ** be represented by a 32-bit integer, then the values returned by |
7922 | ** sqlite3_status() are undefined. |
7923 | ** |
7924 | ** See also: [sqlite3_db_status()] |
7925 | */ |
7926 | SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); |
7927 | SQLITE_API int sqlite3_status64( |
7928 | int op, |
7929 | sqlite3_int64 *pCurrent, |
7930 | sqlite3_int64 *pHighwater, |
7931 | int resetFlag |
7932 | ); |
7933 | |
7934 | |
7935 | /* |
7936 | ** CAPI3REF: Status Parameters |
7937 | ** KEYWORDS: {status parameters} |
7938 | ** |
7939 | ** These integer constants designate various run-time status parameters |
7940 | ** that can be returned by [sqlite3_status()]. |
7941 | ** |
7942 | ** <dl> |
7943 | ** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt> |
7944 | ** <dd>This parameter is the current amount of memory checked out |
7945 | ** using [sqlite3_malloc()], either directly or indirectly. The |
7946 | ** figure includes calls made to [sqlite3_malloc()] by the application |
7947 | ** and internal memory usage by the SQLite library. Auxiliary page-cache |
7948 | ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in |
7949 | ** this parameter. The amount returned is the sum of the allocation |
7950 | ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^ |
7951 | ** |
7952 | ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt> |
7953 | ** <dd>This parameter records the largest memory allocation request |
7954 | ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their |
7955 | ** internal equivalents). Only the value returned in the |
7956 | ** *pHighwater parameter to [sqlite3_status()] is of interest. |
7957 | ** The value written into the *pCurrent parameter is undefined.</dd>)^ |
7958 | ** |
7959 | ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt> |
7960 | ** <dd>This parameter records the number of separate memory allocations |
7961 | ** currently checked out.</dd>)^ |
7962 | ** |
7963 | ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt> |
7964 | ** <dd>This parameter returns the number of pages used out of the |
7965 | ** [pagecache memory allocator] that was configured using |
7966 | ** [SQLITE_CONFIG_PAGECACHE]. The |
7967 | ** value returned is in pages, not in bytes.</dd>)^ |
7968 | ** |
7969 | ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] |
7970 | ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt> |
7971 | ** <dd>This parameter returns the number of bytes of page cache |
7972 | ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE] |
7973 | ** buffer and where forced to overflow to [sqlite3_malloc()]. The |
7974 | ** returned value includes allocations that overflowed because they |
7975 | ** where too large (they were larger than the "sz" parameter to |
7976 | ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because |
7977 | ** no space was left in the page cache.</dd>)^ |
7978 | ** |
7979 | ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt> |
7980 | ** <dd>This parameter records the largest memory allocation request |
7981 | ** handed to the [pagecache memory allocator]. Only the value returned in the |
7982 | ** *pHighwater parameter to [sqlite3_status()] is of interest. |
7983 | ** The value written into the *pCurrent parameter is undefined.</dd>)^ |
7984 | ** |
7985 | ** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt> |
7986 | ** <dd>No longer used.</dd> |
7987 | ** |
7988 | ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt> |
7989 | ** <dd>No longer used.</dd> |
7990 | ** |
7991 | ** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt> |
7992 | ** <dd>No longer used.</dd> |
7993 | ** |
7994 | ** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt> |
7995 | ** <dd>The *pHighwater parameter records the deepest parser stack. |
7996 | ** The *pCurrent value is undefined. The *pHighwater value is only |
7997 | ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^ |
7998 | ** </dl> |
7999 | ** |
8000 | ** New status parameters may be added from time to time. |
8001 | */ |
8002 | #define SQLITE_STATUS_MEMORY_USED 0 |
8003 | #define SQLITE_STATUS_PAGECACHE_USED 1 |
8004 | #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 |
8005 | #define SQLITE_STATUS_SCRATCH_USED 3 /* NOT USED */ |
8006 | #define SQLITE_STATUS_SCRATCH_OVERFLOW 4 /* NOT USED */ |
8007 | #define SQLITE_STATUS_MALLOC_SIZE 5 |
8008 | #define SQLITE_STATUS_PARSER_STACK 6 |
8009 | #define SQLITE_STATUS_PAGECACHE_SIZE 7 |
8010 | #define SQLITE_STATUS_SCRATCH_SIZE 8 /* NOT USED */ |
8011 | #define SQLITE_STATUS_MALLOC_COUNT 9 |
8012 | |
8013 | /* |
8014 | ** CAPI3REF: Database Connection Status |
8015 | ** METHOD: sqlite3 |
8016 | ** |
8017 | ** ^This interface is used to retrieve runtime status information |
8018 | ** about a single [database connection]. ^The first argument is the |
8019 | ** database connection object to be interrogated. ^The second argument |
8020 | ** is an integer constant, taken from the set of |
8021 | ** [SQLITE_DBSTATUS options], that |
8022 | ** determines the parameter to interrogate. The set of |
8023 | ** [SQLITE_DBSTATUS options] is likely |
8024 | ** to grow in future releases of SQLite. |
8025 | ** |
8026 | ** ^The current value of the requested parameter is written into *pCur |
8027 | ** and the highest instantaneous value is written into *pHiwtr. ^If |
8028 | ** the resetFlg is true, then the highest instantaneous value is |
8029 | ** reset back down to the current value. |
8030 | ** |
8031 | ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a |
8032 | ** non-zero [error code] on failure. |
8033 | ** |
8034 | ** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. |
8035 | */ |
8036 | SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); |
8037 | |
8038 | /* |
8039 | ** CAPI3REF: Status Parameters for database connections |
8040 | ** KEYWORDS: {SQLITE_DBSTATUS options} |
8041 | ** |
8042 | ** These constants are the available integer "verbs" that can be passed as |
8043 | ** the second argument to the [sqlite3_db_status()] interface. |
8044 | ** |
8045 | ** New verbs may be added in future releases of SQLite. Existing verbs |
8046 | ** might be discontinued. Applications should check the return code from |
8047 | ** [sqlite3_db_status()] to make sure that the call worked. |
8048 | ** The [sqlite3_db_status()] interface will return a non-zero error code |
8049 | ** if a discontinued or unsupported verb is invoked. |
8050 | ** |
8051 | ** <dl> |
8052 | ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt> |
8053 | ** <dd>This parameter returns the number of lookaside memory slots currently |
8054 | ** checked out.</dd>)^ |
8055 | ** |
8056 | ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt> |
8057 | ** <dd>This parameter returns the number of malloc attempts that were |
8058 | ** satisfied using lookaside memory. Only the high-water value is meaningful; |
8059 | ** the current value is always zero.)^ |
8060 | ** |
8061 | ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]] |
8062 | ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt> |
8063 | ** <dd>This parameter returns the number malloc attempts that might have |
8064 | ** been satisfied using lookaside memory but failed due to the amount of |
8065 | ** memory requested being larger than the lookaside slot size. |
8066 | ** Only the high-water value is meaningful; |
8067 | ** the current value is always zero.)^ |
8068 | ** |
8069 | ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]] |
8070 | ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt> |
8071 | ** <dd>This parameter returns the number malloc attempts that might have |
8072 | ** been satisfied using lookaside memory but failed due to all lookaside |
8073 | ** memory already being in use. |
8074 | ** Only the high-water value is meaningful; |
8075 | ** the current value is always zero.)^ |
8076 | ** |
8077 | ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt> |
8078 | ** <dd>This parameter returns the approximate number of bytes of heap |
8079 | ** memory used by all pager caches associated with the database connection.)^ |
8080 | ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0. |
8081 | ** |
8082 | ** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]] |
8083 | ** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt> |
8084 | ** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a |
8085 | ** pager cache is shared between two or more connections the bytes of heap |
8086 | ** memory used by that pager cache is divided evenly between the attached |
8087 | ** connections.)^ In other words, if none of the pager caches associated |
8088 | ** with the database connection are shared, this request returns the same |
8089 | ** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are |
8090 | ** shared, the value returned by this call will be smaller than that returned |
8091 | ** by DBSTATUS_CACHE_USED. ^The highwater mark associated with |
8092 | ** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0. |
8093 | ** |
8094 | ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt> |
8095 | ** <dd>This parameter returns the approximate number of bytes of heap |
8096 | ** memory used to store the schema for all databases associated |
8097 | ** with the connection - main, temp, and any [ATTACH]-ed databases.)^ |
8098 | ** ^The full amount of memory used by the schemas is reported, even if the |
8099 | ** schema memory is shared with other database connections due to |
8100 | ** [shared cache mode] being enabled. |
8101 | ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0. |
8102 | ** |
8103 | ** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt> |
8104 | ** <dd>This parameter returns the approximate number of bytes of heap |
8105 | ** and lookaside memory used by all prepared statements associated with |
8106 | ** the database connection.)^ |
8107 | ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0. |
8108 | ** </dd> |
8109 | ** |
8110 | ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt> |
8111 | ** <dd>This parameter returns the number of pager cache hits that have |
8112 | ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT |
8113 | ** is always 0. |
8114 | ** </dd> |
8115 | ** |
8116 | ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt> |
8117 | ** <dd>This parameter returns the number of pager cache misses that have |
8118 | ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS |
8119 | ** is always 0. |
8120 | ** </dd> |
8121 | ** |
8122 | ** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt> |
8123 | ** <dd>This parameter returns the number of dirty cache entries that have |
8124 | ** been written to disk. Specifically, the number of pages written to the |
8125 | ** wal file in wal mode databases, or the number of pages written to the |
8126 | ** database file in rollback mode databases. Any pages written as part of |
8127 | ** transaction rollback or database recovery operations are not included. |
8128 | ** If an IO or other error occurs while writing a page to disk, the effect |
8129 | ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The |
8130 | ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0. |
8131 | ** </dd> |
8132 | ** |
8133 | ** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt> |
8134 | ** <dd>This parameter returns the number of dirty cache entries that have |
8135 | ** been written to disk in the middle of a transaction due to the page |
8136 | ** cache overflowing. Transactions are more efficient if they are written |
8137 | ** to disk all at once. When pages spill mid-transaction, that introduces |
8138 | ** additional overhead. This parameter can be used help identify |
8139 | ** inefficiencies that can be resolved by increasing the cache size. |
8140 | ** </dd> |
8141 | ** |
8142 | ** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt> |
8143 | ** <dd>This parameter returns zero for the current value if and only if |
8144 | ** all foreign key constraints (deferred or immediate) have been |
8145 | ** resolved.)^ ^The highwater mark is always 0. |
8146 | ** </dd> |
8147 | ** </dl> |
8148 | */ |
8149 | #define SQLITE_DBSTATUS_LOOKASIDE_USED 0 |
8150 | #define SQLITE_DBSTATUS_CACHE_USED 1 |
8151 | #define SQLITE_DBSTATUS_SCHEMA_USED 2 |
8152 | #define SQLITE_DBSTATUS_STMT_USED 3 |
8153 | #define SQLITE_DBSTATUS_LOOKASIDE_HIT 4 |
8154 | #define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5 |
8155 | #define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6 |
8156 | #define SQLITE_DBSTATUS_CACHE_HIT 7 |
8157 | #define SQLITE_DBSTATUS_CACHE_MISS 8 |
8158 | #define SQLITE_DBSTATUS_CACHE_WRITE 9 |
8159 | #define SQLITE_DBSTATUS_DEFERRED_FKS 10 |
8160 | #define SQLITE_DBSTATUS_CACHE_USED_SHARED 11 |
8161 | #define SQLITE_DBSTATUS_CACHE_SPILL 12 |
8162 | #define SQLITE_DBSTATUS_MAX 12 /* Largest defined DBSTATUS */ |
8163 | |
8164 | |
8165 | /* |
8166 | ** CAPI3REF: Prepared Statement Status |
8167 | ** METHOD: sqlite3_stmt |
8168 | ** |
8169 | ** ^(Each prepared statement maintains various |
8170 | ** [SQLITE_STMTSTATUS counters] that measure the number |
8171 | ** of times it has performed specific operations.)^ These counters can |
8172 | ** be used to monitor the performance characteristics of the prepared |
8173 | ** statements. For example, if the number of table steps greatly exceeds |
8174 | ** the number of table searches or result rows, that would tend to indicate |
8175 | ** that the prepared statement is using a full table scan rather than |
8176 | ** an index. |
8177 | ** |
8178 | ** ^(This interface is used to retrieve and reset counter values from |
8179 | ** a [prepared statement]. The first argument is the prepared statement |
8180 | ** object to be interrogated. The second argument |
8181 | ** is an integer code for a specific [SQLITE_STMTSTATUS counter] |
8182 | ** to be interrogated.)^ |
8183 | ** ^The current value of the requested counter is returned. |
8184 | ** ^If the resetFlg is true, then the counter is reset to zero after this |
8185 | ** interface call returns. |
8186 | ** |
8187 | ** See also: [sqlite3_status()] and [sqlite3_db_status()]. |
8188 | */ |
8189 | SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg); |
8190 | |
8191 | /* |
8192 | ** CAPI3REF: Status Parameters for prepared statements |
8193 | ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters} |
8194 | ** |
8195 | ** These preprocessor macros define integer codes that name counter |
8196 | ** values associated with the [sqlite3_stmt_status()] interface. |
8197 | ** The meanings of the various counters are as follows: |
8198 | ** |
8199 | ** <dl> |
8200 | ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt> |
8201 | ** <dd>^This is the number of times that SQLite has stepped forward in |
8202 | ** a table as part of a full table scan. Large numbers for this counter |
8203 | ** may indicate opportunities for performance improvement through |
8204 | ** careful use of indices.</dd> |
8205 | ** |
8206 | ** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt> |
8207 | ** <dd>^This is the number of sort operations that have occurred. |
8208 | ** A non-zero value in this counter may indicate an opportunity to |
8209 | ** improvement performance through careful use of indices.</dd> |
8210 | ** |
8211 | ** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt> |
8212 | ** <dd>^This is the number of rows inserted into transient indices that |
8213 | ** were created automatically in order to help joins run faster. |
8214 | ** A non-zero value in this counter may indicate an opportunity to |
8215 | ** improvement performance by adding permanent indices that do not |
8216 | ** need to be reinitialized each time the statement is run.</dd> |
8217 | ** |
8218 | ** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt> |
8219 | ** <dd>^This is the number of virtual machine operations executed |
8220 | ** by the prepared statement if that number is less than or equal |
8221 | ** to 2147483647. The number of virtual machine operations can be |
8222 | ** used as a proxy for the total work done by the prepared statement. |
8223 | ** If the number of virtual machine operations exceeds 2147483647 |
8224 | ** then the value returned by this statement status code is undefined. |
8225 | ** |
8226 | ** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt> |
8227 | ** <dd>^This is the number of times that the prepare statement has been |
8228 | ** automatically regenerated due to schema changes or changes to |
8229 | ** [bound parameters] that might affect the query plan. |
8230 | ** |
8231 | ** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt> |
8232 | ** <dd>^This is the number of times that the prepared statement has |
8233 | ** been run. A single "run" for the purposes of this counter is one |
8234 | ** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()]. |
8235 | ** The counter is incremented on the first [sqlite3_step()] call of each |
8236 | ** cycle. |
8237 | ** |
8238 | ** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt> |
8239 | ** <dd>^This is the approximate number of bytes of heap memory |
8240 | ** used to store the prepared statement. ^This value is not actually |
8241 | ** a counter, and so the resetFlg parameter to sqlite3_stmt_status() |
8242 | ** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED. |
8243 | ** </dd> |
8244 | ** </dl> |
8245 | */ |
8246 | #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 |
8247 | #define SQLITE_STMTSTATUS_SORT 2 |
8248 | #define SQLITE_STMTSTATUS_AUTOINDEX 3 |
8249 | #define SQLITE_STMTSTATUS_VM_STEP 4 |
8250 | #define SQLITE_STMTSTATUS_REPREPARE 5 |
8251 | #define SQLITE_STMTSTATUS_RUN 6 |
8252 | #define SQLITE_STMTSTATUS_MEMUSED 99 |
8253 | |
8254 | /* |
8255 | ** CAPI3REF: Custom Page Cache Object |
8256 | ** |
8257 | ** The sqlite3_pcache type is opaque. It is implemented by |
8258 | ** the pluggable module. The SQLite core has no knowledge of |
8259 | ** its size or internal structure and never deals with the |
8260 | ** sqlite3_pcache object except by holding and passing pointers |
8261 | ** to the object. |
8262 | ** |
8263 | ** See [sqlite3_pcache_methods2] for additional information. |
8264 | */ |
8265 | typedef struct sqlite3_pcache sqlite3_pcache; |
8266 | |
8267 | /* |
8268 | ** CAPI3REF: Custom Page Cache Object |
8269 | ** |
8270 | ** The sqlite3_pcache_page object represents a single page in the |
8271 | ** page cache. The page cache will allocate instances of this |
8272 | ** object. Various methods of the page cache use pointers to instances |
8273 | ** of this object as parameters or as their return value. |
8274 | ** |
8275 | ** See [sqlite3_pcache_methods2] for additional information. |
8276 | */ |
8277 | typedef struct sqlite3_pcache_page sqlite3_pcache_page; |
8278 | struct sqlite3_pcache_page { |
8279 | void *pBuf; /* The content of the page */ |
8280 | void *; /* Extra information associated with the page */ |
8281 | }; |
8282 | |
8283 | /* |
8284 | ** CAPI3REF: Application Defined Page Cache. |
8285 | ** KEYWORDS: {page cache} |
8286 | ** |
8287 | ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can |
8288 | ** register an alternative page cache implementation by passing in an |
8289 | ** instance of the sqlite3_pcache_methods2 structure.)^ |
8290 | ** In many applications, most of the heap memory allocated by |
8291 | ** SQLite is used for the page cache. |
8292 | ** By implementing a |
8293 | ** custom page cache using this API, an application can better control |
8294 | ** the amount of memory consumed by SQLite, the way in which |
8295 | ** that memory is allocated and released, and the policies used to |
8296 | ** determine exactly which parts of a database file are cached and for |
8297 | ** how long. |
8298 | ** |
8299 | ** The alternative page cache mechanism is an |
8300 | ** extreme measure that is only needed by the most demanding applications. |
8301 | ** The built-in page cache is recommended for most uses. |
8302 | ** |
8303 | ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an |
8304 | ** internal buffer by SQLite within the call to [sqlite3_config]. Hence |
8305 | ** the application may discard the parameter after the call to |
8306 | ** [sqlite3_config()] returns.)^ |
8307 | ** |
8308 | ** [[the xInit() page cache method]] |
8309 | ** ^(The xInit() method is called once for each effective |
8310 | ** call to [sqlite3_initialize()])^ |
8311 | ** (usually only once during the lifetime of the process). ^(The xInit() |
8312 | ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^ |
8313 | ** The intent of the xInit() method is to set up global data structures |
8314 | ** required by the custom page cache implementation. |
8315 | ** ^(If the xInit() method is NULL, then the |
8316 | ** built-in default page cache is used instead of the application defined |
8317 | ** page cache.)^ |
8318 | ** |
8319 | ** [[the xShutdown() page cache method]] |
8320 | ** ^The xShutdown() method is called by [sqlite3_shutdown()]. |
8321 | ** It can be used to clean up |
8322 | ** any outstanding resources before process shutdown, if required. |
8323 | ** ^The xShutdown() method may be NULL. |
8324 | ** |
8325 | ** ^SQLite automatically serializes calls to the xInit method, |
8326 | ** so the xInit method need not be threadsafe. ^The |
8327 | ** xShutdown method is only called from [sqlite3_shutdown()] so it does |
8328 | ** not need to be threadsafe either. All other methods must be threadsafe |
8329 | ** in multithreaded applications. |
8330 | ** |
8331 | ** ^SQLite will never invoke xInit() more than once without an intervening |
8332 | ** call to xShutdown(). |
8333 | ** |
8334 | ** [[the xCreate() page cache methods]] |
8335 | ** ^SQLite invokes the xCreate() method to construct a new cache instance. |
8336 | ** SQLite will typically create one cache instance for each open database file, |
8337 | ** though this is not guaranteed. ^The |
8338 | ** first parameter, szPage, is the size in bytes of the pages that must |
8339 | ** be allocated by the cache. ^szPage will always a power of two. ^The |
8340 | ** second parameter szExtra is a number of bytes of extra storage |
8341 | ** associated with each page cache entry. ^The szExtra parameter will |
8342 | ** a number less than 250. SQLite will use the |
8343 | ** extra szExtra bytes on each page to store metadata about the underlying |
8344 | ** database page on disk. The value passed into szExtra depends |
8345 | ** on the SQLite version, the target platform, and how SQLite was compiled. |
8346 | ** ^The third argument to xCreate(), bPurgeable, is true if the cache being |
8347 | ** created will be used to cache database pages of a file stored on disk, or |
8348 | ** false if it is used for an in-memory database. The cache implementation |
8349 | ** does not have to do anything special based with the value of bPurgeable; |
8350 | ** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will |
8351 | ** never invoke xUnpin() except to deliberately delete a page. |
8352 | ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to |
8353 | ** false will always have the "discard" flag set to true. |
8354 | ** ^Hence, a cache created with bPurgeable false will |
8355 | ** never contain any unpinned pages. |
8356 | ** |
8357 | ** [[the xCachesize() page cache method]] |
8358 | ** ^(The xCachesize() method may be called at any time by SQLite to set the |
8359 | ** suggested maximum cache-size (number of pages stored by) the cache |
8360 | ** instance passed as the first argument. This is the value configured using |
8361 | ** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable |
8362 | ** parameter, the implementation is not required to do anything with this |
8363 | ** value; it is advisory only. |
8364 | ** |
8365 | ** [[the xPagecount() page cache methods]] |
8366 | ** The xPagecount() method must return the number of pages currently |
8367 | ** stored in the cache, both pinned and unpinned. |
8368 | ** |
8369 | ** [[the xFetch() page cache methods]] |
8370 | ** The xFetch() method locates a page in the cache and returns a pointer to |
8371 | ** an sqlite3_pcache_page object associated with that page, or a NULL pointer. |
8372 | ** The pBuf element of the returned sqlite3_pcache_page object will be a |
8373 | ** pointer to a buffer of szPage bytes used to store the content of a |
8374 | ** single database page. The pExtra element of sqlite3_pcache_page will be |
8375 | ** a pointer to the szExtra bytes of extra storage that SQLite has requested |
8376 | ** for each entry in the page cache. |
8377 | ** |
8378 | ** The page to be fetched is determined by the key. ^The minimum key value |
8379 | ** is 1. After it has been retrieved using xFetch, the page is considered |
8380 | ** to be "pinned". |
8381 | ** |
8382 | ** If the requested page is already in the page cache, then the page cache |
8383 | ** implementation must return a pointer to the page buffer with its content |
8384 | ** intact. If the requested page is not already in the cache, then the |
8385 | ** cache implementation should use the value of the createFlag |
8386 | ** parameter to help it determined what action to take: |
8387 | ** |
8388 | ** <table border=1 width=85% align=center> |
8389 | ** <tr><th> createFlag <th> Behavior when page is not already in cache |
8390 | ** <tr><td> 0 <td> Do not allocate a new page. Return NULL. |
8391 | ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so. |
8392 | ** Otherwise return NULL. |
8393 | ** <tr><td> 2 <td> Make every effort to allocate a new page. Only return |
8394 | ** NULL if allocating a new page is effectively impossible. |
8395 | ** </table> |
8396 | ** |
8397 | ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite |
8398 | ** will only use a createFlag of 2 after a prior call with a createFlag of 1 |
8399 | ** failed.)^ In between the xFetch() calls, SQLite may |
8400 | ** attempt to unpin one or more cache pages by spilling the content of |
8401 | ** pinned pages to disk and synching the operating system disk cache. |
8402 | ** |
8403 | ** [[the xUnpin() page cache method]] |
8404 | ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page |
8405 | ** as its second argument. If the third parameter, discard, is non-zero, |
8406 | ** then the page must be evicted from the cache. |
8407 | ** ^If the discard parameter is |
8408 | ** zero, then the page may be discarded or retained at the discretion of |
8409 | ** page cache implementation. ^The page cache implementation |
8410 | ** may choose to evict unpinned pages at any time. |
8411 | ** |
8412 | ** The cache must not perform any reference counting. A single |
8413 | ** call to xUnpin() unpins the page regardless of the number of prior calls |
8414 | ** to xFetch(). |
8415 | ** |
8416 | ** [[the xRekey() page cache methods]] |
8417 | ** The xRekey() method is used to change the key value associated with the |
8418 | ** page passed as the second argument. If the cache |
8419 | ** previously contains an entry associated with newKey, it must be |
8420 | ** discarded. ^Any prior cache entry associated with newKey is guaranteed not |
8421 | ** to be pinned. |
8422 | ** |
8423 | ** When SQLite calls the xTruncate() method, the cache must discard all |
8424 | ** existing cache entries with page numbers (keys) greater than or equal |
8425 | ** to the value of the iLimit parameter passed to xTruncate(). If any |
8426 | ** of these pages are pinned, they are implicitly unpinned, meaning that |
8427 | ** they can be safely discarded. |
8428 | ** |
8429 | ** [[the xDestroy() page cache method]] |
8430 | ** ^The xDestroy() method is used to delete a cache allocated by xCreate(). |
8431 | ** All resources associated with the specified cache should be freed. ^After |
8432 | ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] |
8433 | ** handle invalid, and will not use it with any other sqlite3_pcache_methods2 |
8434 | ** functions. |
8435 | ** |
8436 | ** [[the xShrink() page cache method]] |
8437 | ** ^SQLite invokes the xShrink() method when it wants the page cache to |
8438 | ** free up as much of heap memory as possible. The page cache implementation |
8439 | ** is not obligated to free any memory, but well-behaved implementations should |
8440 | ** do their best. |
8441 | */ |
8442 | typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2; |
8443 | struct sqlite3_pcache_methods2 { |
8444 | int iVersion; |
8445 | void *pArg; |
8446 | int (*xInit)(void*); |
8447 | void (*xShutdown)(void*); |
8448 | sqlite3_pcache *(*xCreate)(int szPage, int , int bPurgeable); |
8449 | void (*xCachesize)(sqlite3_pcache*, int nCachesize); |
8450 | int (*xPagecount)(sqlite3_pcache*); |
8451 | sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); |
8452 | void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard); |
8453 | void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, |
8454 | unsigned oldKey, unsigned newKey); |
8455 | void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); |
8456 | void (*xDestroy)(sqlite3_pcache*); |
8457 | void (*xShrink)(sqlite3_pcache*); |
8458 | }; |
8459 | |
8460 | /* |
8461 | ** This is the obsolete pcache_methods object that has now been replaced |
8462 | ** by sqlite3_pcache_methods2. This object is not used by SQLite. It is |
8463 | ** retained in the header file for backwards compatibility only. |
8464 | */ |
8465 | typedef struct sqlite3_pcache_methods sqlite3_pcache_methods; |
8466 | struct sqlite3_pcache_methods { |
8467 | void *pArg; |
8468 | int (*xInit)(void*); |
8469 | void (*xShutdown)(void*); |
8470 | sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); |
8471 | void (*xCachesize)(sqlite3_pcache*, int nCachesize); |
8472 | int (*xPagecount)(sqlite3_pcache*); |
8473 | void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); |
8474 | void (*xUnpin)(sqlite3_pcache*, void*, int discard); |
8475 | void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); |
8476 | void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); |
8477 | void (*xDestroy)(sqlite3_pcache*); |
8478 | }; |
8479 | |
8480 | |
8481 | /* |
8482 | ** CAPI3REF: Online Backup Object |
8483 | ** |
8484 | ** The sqlite3_backup object records state information about an ongoing |
8485 | ** online backup operation. ^The sqlite3_backup object is created by |
8486 | ** a call to [sqlite3_backup_init()] and is destroyed by a call to |
8487 | ** [sqlite3_backup_finish()]. |
8488 | ** |
8489 | ** See Also: [Using the SQLite Online Backup API] |
8490 | */ |
8491 | typedef struct sqlite3_backup sqlite3_backup; |
8492 | |
8493 | /* |
8494 | ** CAPI3REF: Online Backup API. |
8495 | ** |
8496 | ** The backup API copies the content of one database into another. |
8497 | ** It is useful either for creating backups of databases or |
8498 | ** for copying in-memory databases to or from persistent files. |
8499 | ** |
8500 | ** See Also: [Using the SQLite Online Backup API] |
8501 | ** |
8502 | ** ^SQLite holds a write transaction open on the destination database file |
8503 | ** for the duration of the backup operation. |
8504 | ** ^The source database is read-locked only while it is being read; |
8505 | ** it is not locked continuously for the entire backup operation. |
8506 | ** ^Thus, the backup may be performed on a live source database without |
8507 | ** preventing other database connections from |
8508 | ** reading or writing to the source database while the backup is underway. |
8509 | ** |
8510 | ** ^(To perform a backup operation: |
8511 | ** <ol> |
8512 | ** <li><b>sqlite3_backup_init()</b> is called once to initialize the |
8513 | ** backup, |
8514 | ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer |
8515 | ** the data between the two databases, and finally |
8516 | ** <li><b>sqlite3_backup_finish()</b> is called to release all resources |
8517 | ** associated with the backup operation. |
8518 | ** </ol>)^ |
8519 | ** There should be exactly one call to sqlite3_backup_finish() for each |
8520 | ** successful call to sqlite3_backup_init(). |
8521 | ** |
8522 | ** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b> |
8523 | ** |
8524 | ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the |
8525 | ** [database connection] associated with the destination database |
8526 | ** and the database name, respectively. |
8527 | ** ^The database name is "main" for the main database, "temp" for the |
8528 | ** temporary database, or the name specified after the AS keyword in |
8529 | ** an [ATTACH] statement for an attached database. |
8530 | ** ^The S and M arguments passed to |
8531 | ** sqlite3_backup_init(D,N,S,M) identify the [database connection] |
8532 | ** and database name of the source database, respectively. |
8533 | ** ^The source and destination [database connections] (parameters S and D) |
8534 | ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with |
8535 | ** an error. |
8536 | ** |
8537 | ** ^A call to sqlite3_backup_init() will fail, returning NULL, if |
8538 | ** there is already a read or read-write transaction open on the |
8539 | ** destination database. |
8540 | ** |
8541 | ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is |
8542 | ** returned and an error code and error message are stored in the |
8543 | ** destination [database connection] D. |
8544 | ** ^The error code and message for the failed call to sqlite3_backup_init() |
8545 | ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or |
8546 | ** [sqlite3_errmsg16()] functions. |
8547 | ** ^A successful call to sqlite3_backup_init() returns a pointer to an |
8548 | ** [sqlite3_backup] object. |
8549 | ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and |
8550 | ** sqlite3_backup_finish() functions to perform the specified backup |
8551 | ** operation. |
8552 | ** |
8553 | ** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b> |
8554 | ** |
8555 | ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between |
8556 | ** the source and destination databases specified by [sqlite3_backup] object B. |
8557 | ** ^If N is negative, all remaining source pages are copied. |
8558 | ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there |
8559 | ** are still more pages to be copied, then the function returns [SQLITE_OK]. |
8560 | ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages |
8561 | ** from source to destination, then it returns [SQLITE_DONE]. |
8562 | ** ^If an error occurs while running sqlite3_backup_step(B,N), |
8563 | ** then an [error code] is returned. ^As well as [SQLITE_OK] and |
8564 | ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], |
8565 | ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an |
8566 | ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. |
8567 | ** |
8568 | ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if |
8569 | ** <ol> |
8570 | ** <li> the destination database was opened read-only, or |
8571 | ** <li> the destination database is using write-ahead-log journaling |
8572 | ** and the destination and source page sizes differ, or |
8573 | ** <li> the destination database is an in-memory database and the |
8574 | ** destination and source page sizes differ. |
8575 | ** </ol>)^ |
8576 | ** |
8577 | ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then |
8578 | ** the [sqlite3_busy_handler | busy-handler function] |
8579 | ** is invoked (if one is specified). ^If the |
8580 | ** busy-handler returns non-zero before the lock is available, then |
8581 | ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to |
8582 | ** sqlite3_backup_step() can be retried later. ^If the source |
8583 | ** [database connection] |
8584 | ** is being used to write to the source database when sqlite3_backup_step() |
8585 | ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this |
8586 | ** case the call to sqlite3_backup_step() can be retried later on. ^(If |
8587 | ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or |
8588 | ** [SQLITE_READONLY] is returned, then |
8589 | ** there is no point in retrying the call to sqlite3_backup_step(). These |
8590 | ** errors are considered fatal.)^ The application must accept |
8591 | ** that the backup operation has failed and pass the backup operation handle |
8592 | ** to the sqlite3_backup_finish() to release associated resources. |
8593 | ** |
8594 | ** ^The first call to sqlite3_backup_step() obtains an exclusive lock |
8595 | ** on the destination file. ^The exclusive lock is not released until either |
8596 | ** sqlite3_backup_finish() is called or the backup operation is complete |
8597 | ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to |
8598 | ** sqlite3_backup_step() obtains a [shared lock] on the source database that |
8599 | ** lasts for the duration of the sqlite3_backup_step() call. |
8600 | ** ^Because the source database is not locked between calls to |
8601 | ** sqlite3_backup_step(), the source database may be modified mid-way |
8602 | ** through the backup process. ^If the source database is modified by an |
8603 | ** external process or via a database connection other than the one being |
8604 | ** used by the backup operation, then the backup will be automatically |
8605 | ** restarted by the next call to sqlite3_backup_step(). ^If the source |
8606 | ** database is modified by the using the same database connection as is used |
8607 | ** by the backup operation, then the backup database is automatically |
8608 | ** updated at the same time. |
8609 | ** |
8610 | ** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b> |
8611 | ** |
8612 | ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the |
8613 | ** application wishes to abandon the backup operation, the application |
8614 | ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish(). |
8615 | ** ^The sqlite3_backup_finish() interfaces releases all |
8616 | ** resources associated with the [sqlite3_backup] object. |
8617 | ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any |
8618 | ** active write-transaction on the destination database is rolled back. |
8619 | ** The [sqlite3_backup] object is invalid |
8620 | ** and may not be used following a call to sqlite3_backup_finish(). |
8621 | ** |
8622 | ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no |
8623 | ** sqlite3_backup_step() errors occurred, regardless or whether or not |
8624 | ** sqlite3_backup_step() completed. |
8625 | ** ^If an out-of-memory condition or IO error occurred during any prior |
8626 | ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then |
8627 | ** sqlite3_backup_finish() returns the corresponding [error code]. |
8628 | ** |
8629 | ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() |
8630 | ** is not a permanent error and does not affect the return value of |
8631 | ** sqlite3_backup_finish(). |
8632 | ** |
8633 | ** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]] |
8634 | ** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b> |
8635 | ** |
8636 | ** ^The sqlite3_backup_remaining() routine returns the number of pages still |
8637 | ** to be backed up at the conclusion of the most recent sqlite3_backup_step(). |
8638 | ** ^The sqlite3_backup_pagecount() routine returns the total number of pages |
8639 | ** in the source database at the conclusion of the most recent |
8640 | ** sqlite3_backup_step(). |
8641 | ** ^(The values returned by these functions are only updated by |
8642 | ** sqlite3_backup_step(). If the source database is modified in a way that |
8643 | ** changes the size of the source database or the number of pages remaining, |
8644 | ** those changes are not reflected in the output of sqlite3_backup_pagecount() |
8645 | ** and sqlite3_backup_remaining() until after the next |
8646 | ** sqlite3_backup_step().)^ |
8647 | ** |
8648 | ** <b>Concurrent Usage of Database Handles</b> |
8649 | ** |
8650 | ** ^The source [database connection] may be used by the application for other |
8651 | ** purposes while a backup operation is underway or being initialized. |
8652 | ** ^If SQLite is compiled and configured to support threadsafe database |
8653 | ** connections, then the source database connection may be used concurrently |
8654 | ** from within other threads. |
8655 | ** |
8656 | ** However, the application must guarantee that the destination |
8657 | ** [database connection] is not passed to any other API (by any thread) after |
8658 | ** sqlite3_backup_init() is called and before the corresponding call to |
8659 | ** sqlite3_backup_finish(). SQLite does not currently check to see |
8660 | ** if the application incorrectly accesses the destination [database connection] |
8661 | ** and so no error code is reported, but the operations may malfunction |
8662 | ** nevertheless. Use of the destination database connection while a |
8663 | ** backup is in progress might also also cause a mutex deadlock. |
8664 | ** |
8665 | ** If running in [shared cache mode], the application must |
8666 | ** guarantee that the shared cache used by the destination database |
8667 | ** is not accessed while the backup is running. In practice this means |
8668 | ** that the application must guarantee that the disk file being |
8669 | ** backed up to is not accessed by any connection within the process, |
8670 | ** not just the specific connection that was passed to sqlite3_backup_init(). |
8671 | ** |
8672 | ** The [sqlite3_backup] object itself is partially threadsafe. Multiple |
8673 | ** threads may safely make multiple concurrent calls to sqlite3_backup_step(). |
8674 | ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() |
8675 | ** APIs are not strictly speaking threadsafe. If they are invoked at the |
8676 | ** same time as another thread is invoking sqlite3_backup_step() it is |
8677 | ** possible that they return invalid values. |
8678 | */ |
8679 | SQLITE_API sqlite3_backup *sqlite3_backup_init( |
8680 | sqlite3 *pDest, /* Destination database handle */ |
8681 | const char *zDestName, /* Destination database name */ |
8682 | sqlite3 *pSource, /* Source database handle */ |
8683 | const char *zSourceName /* Source database name */ |
8684 | ); |
8685 | SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage); |
8686 | SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p); |
8687 | SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p); |
8688 | SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p); |
8689 | |
8690 | /* |
8691 | ** CAPI3REF: Unlock Notification |
8692 | ** METHOD: sqlite3 |
8693 | ** |
8694 | ** ^When running in shared-cache mode, a database operation may fail with |
8695 | ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or |
8696 | ** individual tables within the shared-cache cannot be obtained. See |
8697 | ** [SQLite Shared-Cache Mode] for a description of shared-cache locking. |
8698 | ** ^This API may be used to register a callback that SQLite will invoke |
8699 | ** when the connection currently holding the required lock relinquishes it. |
8700 | ** ^This API is only available if the library was compiled with the |
8701 | ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. |
8702 | ** |
8703 | ** See Also: [Using the SQLite Unlock Notification Feature]. |
8704 | ** |
8705 | ** ^Shared-cache locks are released when a database connection concludes |
8706 | ** its current transaction, either by committing it or rolling it back. |
8707 | ** |
8708 | ** ^When a connection (known as the blocked connection) fails to obtain a |
8709 | ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the |
8710 | ** identity of the database connection (the blocking connection) that |
8711 | ** has locked the required resource is stored internally. ^After an |
8712 | ** application receives an SQLITE_LOCKED error, it may call the |
8713 | ** sqlite3_unlock_notify() method with the blocked connection handle as |
8714 | ** the first argument to register for a callback that will be invoked |
8715 | ** when the blocking connections current transaction is concluded. ^The |
8716 | ** callback is invoked from within the [sqlite3_step] or [sqlite3_close] |
8717 | ** call that concludes the blocking connection's transaction. |
8718 | ** |
8719 | ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application, |
8720 | ** there is a chance that the blocking connection will have already |
8721 | ** concluded its transaction by the time sqlite3_unlock_notify() is invoked. |
8722 | ** If this happens, then the specified callback is invoked immediately, |
8723 | ** from within the call to sqlite3_unlock_notify().)^ |
8724 | ** |
8725 | ** ^If the blocked connection is attempting to obtain a write-lock on a |
8726 | ** shared-cache table, and more than one other connection currently holds |
8727 | ** a read-lock on the same table, then SQLite arbitrarily selects one of |
8728 | ** the other connections to use as the blocking connection. |
8729 | ** |
8730 | ** ^(There may be at most one unlock-notify callback registered by a |
8731 | ** blocked connection. If sqlite3_unlock_notify() is called when the |
8732 | ** blocked connection already has a registered unlock-notify callback, |
8733 | ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is |
8734 | ** called with a NULL pointer as its second argument, then any existing |
8735 | ** unlock-notify callback is canceled. ^The blocked connections |
8736 | ** unlock-notify callback may also be canceled by closing the blocked |
8737 | ** connection using [sqlite3_close()]. |
8738 | ** |
8739 | ** The unlock-notify callback is not reentrant. If an application invokes |
8740 | ** any sqlite3_xxx API functions from within an unlock-notify callback, a |
8741 | ** crash or deadlock may be the result. |
8742 | ** |
8743 | ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always |
8744 | ** returns SQLITE_OK. |
8745 | ** |
8746 | ** <b>Callback Invocation Details</b> |
8747 | ** |
8748 | ** When an unlock-notify callback is registered, the application provides a |
8749 | ** single void* pointer that is passed to the callback when it is invoked. |
8750 | ** However, the signature of the callback function allows SQLite to pass |
8751 | ** it an array of void* context pointers. The first argument passed to |
8752 | ** an unlock-notify callback is a pointer to an array of void* pointers, |
8753 | ** and the second is the number of entries in the array. |
8754 | ** |
8755 | ** When a blocking connection's transaction is concluded, there may be |
8756 | ** more than one blocked connection that has registered for an unlock-notify |
8757 | ** callback. ^If two or more such blocked connections have specified the |
8758 | ** same callback function, then instead of invoking the callback function |
8759 | ** multiple times, it is invoked once with the set of void* context pointers |
8760 | ** specified by the blocked connections bundled together into an array. |
8761 | ** This gives the application an opportunity to prioritize any actions |
8762 | ** related to the set of unblocked database connections. |
8763 | ** |
8764 | ** <b>Deadlock Detection</b> |
8765 | ** |
8766 | ** Assuming that after registering for an unlock-notify callback a |
8767 | ** database waits for the callback to be issued before taking any further |
8768 | ** action (a reasonable assumption), then using this API may cause the |
8769 | ** application to deadlock. For example, if connection X is waiting for |
8770 | ** connection Y's transaction to be concluded, and similarly connection |
8771 | ** Y is waiting on connection X's transaction, then neither connection |
8772 | ** will proceed and the system may remain deadlocked indefinitely. |
8773 | ** |
8774 | ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock |
8775 | ** detection. ^If a given call to sqlite3_unlock_notify() would put the |
8776 | ** system in a deadlocked state, then SQLITE_LOCKED is returned and no |
8777 | ** unlock-notify callback is registered. The system is said to be in |
8778 | ** a deadlocked state if connection A has registered for an unlock-notify |
8779 | ** callback on the conclusion of connection B's transaction, and connection |
8780 | ** B has itself registered for an unlock-notify callback when connection |
8781 | ** A's transaction is concluded. ^Indirect deadlock is also detected, so |
8782 | ** the system is also considered to be deadlocked if connection B has |
8783 | ** registered for an unlock-notify callback on the conclusion of connection |
8784 | ** C's transaction, where connection C is waiting on connection A. ^Any |
8785 | ** number of levels of indirection are allowed. |
8786 | ** |
8787 | ** <b>The "DROP TABLE" Exception</b> |
8788 | ** |
8789 | ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost |
8790 | ** always appropriate to call sqlite3_unlock_notify(). There is however, |
8791 | ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, |
8792 | ** SQLite checks if there are any currently executing SELECT statements |
8793 | ** that belong to the same connection. If there are, SQLITE_LOCKED is |
8794 | ** returned. In this case there is no "blocking connection", so invoking |
8795 | ** sqlite3_unlock_notify() results in the unlock-notify callback being |
8796 | ** invoked immediately. If the application then re-attempts the "DROP TABLE" |
8797 | ** or "DROP INDEX" query, an infinite loop might be the result. |
8798 | ** |
8799 | ** One way around this problem is to check the extended error code returned |
8800 | ** by an sqlite3_step() call. ^(If there is a blocking connection, then the |
8801 | ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in |
8802 | ** the special "DROP TABLE/INDEX" case, the extended error code is just |
8803 | ** SQLITE_LOCKED.)^ |
8804 | */ |
8805 | SQLITE_API int sqlite3_unlock_notify( |
8806 | sqlite3 *pBlocked, /* Waiting connection */ |
8807 | void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ |
8808 | void *pNotifyArg /* Argument to pass to xNotify */ |
8809 | ); |
8810 | |
8811 | |
8812 | /* |
8813 | ** CAPI3REF: String Comparison |
8814 | ** |
8815 | ** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications |
8816 | ** and extensions to compare the contents of two buffers containing UTF-8 |
8817 | ** strings in a case-independent fashion, using the same definition of "case |
8818 | ** independence" that SQLite uses internally when comparing identifiers. |
8819 | */ |
8820 | SQLITE_API int sqlite3_stricmp(const char *, const char *); |
8821 | SQLITE_API int sqlite3_strnicmp(const char *, const char *, int); |
8822 | |
8823 | /* |
8824 | ** CAPI3REF: String Globbing |
8825 | * |
8826 | ** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if |
8827 | ** string X matches the [GLOB] pattern P. |
8828 | ** ^The definition of [GLOB] pattern matching used in |
8829 | ** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the |
8830 | ** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function |
8831 | ** is case sensitive. |
8832 | ** |
8833 | ** Note that this routine returns zero on a match and non-zero if the strings |
8834 | ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. |
8835 | ** |
8836 | ** See also: [sqlite3_strlike()]. |
8837 | */ |
8838 | SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr); |
8839 | |
8840 | /* |
8841 | ** CAPI3REF: String LIKE Matching |
8842 | * |
8843 | ** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if |
8844 | ** string X matches the [LIKE] pattern P with escape character E. |
8845 | ** ^The definition of [LIKE] pattern matching used in |
8846 | ** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E" |
8847 | ** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without |
8848 | ** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0. |
8849 | ** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case |
8850 | ** insensitive - equivalent upper and lower case ASCII characters match |
8851 | ** one another. |
8852 | ** |
8853 | ** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though |
8854 | ** only ASCII characters are case folded. |
8855 | ** |
8856 | ** Note that this routine returns zero on a match and non-zero if the strings |
8857 | ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. |
8858 | ** |
8859 | ** See also: [sqlite3_strglob()]. |
8860 | */ |
8861 | SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc); |
8862 | |
8863 | /* |
8864 | ** CAPI3REF: Error Logging Interface |
8865 | ** |
8866 | ** ^The [sqlite3_log()] interface writes a message into the [error log] |
8867 | ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()]. |
8868 | ** ^If logging is enabled, the zFormat string and subsequent arguments are |
8869 | ** used with [sqlite3_snprintf()] to generate the final output string. |
8870 | ** |
8871 | ** The sqlite3_log() interface is intended for use by extensions such as |
8872 | ** virtual tables, collating functions, and SQL functions. While there is |
8873 | ** nothing to prevent an application from calling sqlite3_log(), doing so |
8874 | ** is considered bad form. |
8875 | ** |
8876 | ** The zFormat string must not be NULL. |
8877 | ** |
8878 | ** To avoid deadlocks and other threading problems, the sqlite3_log() routine |
8879 | ** will not use dynamically allocated memory. The log message is stored in |
8880 | ** a fixed-length buffer on the stack. If the log message is longer than |
8881 | ** a few hundred characters, it will be truncated to the length of the |
8882 | ** buffer. |
8883 | */ |
8884 | SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...); |
8885 | |
8886 | /* |
8887 | ** CAPI3REF: Write-Ahead Log Commit Hook |
8888 | ** METHOD: sqlite3 |
8889 | ** |
8890 | ** ^The [sqlite3_wal_hook()] function is used to register a callback that |
8891 | ** is invoked each time data is committed to a database in wal mode. |
8892 | ** |
8893 | ** ^(The callback is invoked by SQLite after the commit has taken place and |
8894 | ** the associated write-lock on the database released)^, so the implementation |
8895 | ** may read, write or [checkpoint] the database as required. |
8896 | ** |
8897 | ** ^The first parameter passed to the callback function when it is invoked |
8898 | ** is a copy of the third parameter passed to sqlite3_wal_hook() when |
8899 | ** registering the callback. ^The second is a copy of the database handle. |
8900 | ** ^The third parameter is the name of the database that was written to - |
8901 | ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter |
8902 | ** is the number of pages currently in the write-ahead log file, |
8903 | ** including those that were just committed. |
8904 | ** |
8905 | ** The callback function should normally return [SQLITE_OK]. ^If an error |
8906 | ** code is returned, that error will propagate back up through the |
8907 | ** SQLite code base to cause the statement that provoked the callback |
8908 | ** to report an error, though the commit will have still occurred. If the |
8909 | ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value |
8910 | ** that does not correspond to any valid SQLite error code, the results |
8911 | ** are undefined. |
8912 | ** |
8913 | ** A single database handle may have at most a single write-ahead log callback |
8914 | ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any |
8915 | ** previously registered write-ahead log callback. ^Note that the |
8916 | ** [sqlite3_wal_autocheckpoint()] interface and the |
8917 | ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will |
8918 | ** overwrite any prior [sqlite3_wal_hook()] settings. |
8919 | */ |
8920 | SQLITE_API void *sqlite3_wal_hook( |
8921 | sqlite3*, |
8922 | int(*)(void *,sqlite3*,const char*,int), |
8923 | void* |
8924 | ); |
8925 | |
8926 | /* |
8927 | ** CAPI3REF: Configure an auto-checkpoint |
8928 | ** METHOD: sqlite3 |
8929 | ** |
8930 | ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around |
8931 | ** [sqlite3_wal_hook()] that causes any database on [database connection] D |
8932 | ** to automatically [checkpoint] |
8933 | ** after committing a transaction if there are N or |
8934 | ** more frames in the [write-ahead log] file. ^Passing zero or |
8935 | ** a negative value as the nFrame parameter disables automatic |
8936 | ** checkpoints entirely. |
8937 | ** |
8938 | ** ^The callback registered by this function replaces any existing callback |
8939 | ** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback |
8940 | ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism |
8941 | ** configured by this function. |
8942 | ** |
8943 | ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface |
8944 | ** from SQL. |
8945 | ** |
8946 | ** ^Checkpoints initiated by this mechanism are |
8947 | ** [sqlite3_wal_checkpoint_v2|PASSIVE]. |
8948 | ** |
8949 | ** ^Every new [database connection] defaults to having the auto-checkpoint |
8950 | ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT] |
8951 | ** pages. The use of this interface |
8952 | ** is only necessary if the default setting is found to be suboptimal |
8953 | ** for a particular application. |
8954 | */ |
8955 | SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N); |
8956 | |
8957 | /* |
8958 | ** CAPI3REF: Checkpoint a database |
8959 | ** METHOD: sqlite3 |
8960 | ** |
8961 | ** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to |
8962 | ** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^ |
8963 | ** |
8964 | ** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the |
8965 | ** [write-ahead log] for database X on [database connection] D to be |
8966 | ** transferred into the database file and for the write-ahead log to |
8967 | ** be reset. See the [checkpointing] documentation for addition |
8968 | ** information. |
8969 | ** |
8970 | ** This interface used to be the only way to cause a checkpoint to |
8971 | ** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()] |
8972 | ** interface was added. This interface is retained for backwards |
8973 | ** compatibility and as a convenience for applications that need to manually |
8974 | ** start a callback but which do not need the full power (and corresponding |
8975 | ** complication) of [sqlite3_wal_checkpoint_v2()]. |
8976 | */ |
8977 | SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb); |
8978 | |
8979 | /* |
8980 | ** CAPI3REF: Checkpoint a database |
8981 | ** METHOD: sqlite3 |
8982 | ** |
8983 | ** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint |
8984 | ** operation on database X of [database connection] D in mode M. Status |
8985 | ** information is written back into integers pointed to by L and C.)^ |
8986 | ** ^(The M parameter must be a valid [checkpoint mode]:)^ |
8987 | ** |
8988 | ** <dl> |
8989 | ** <dt>SQLITE_CHECKPOINT_PASSIVE<dd> |
8990 | ** ^Checkpoint as many frames as possible without waiting for any database |
8991 | ** readers or writers to finish, then sync the database file if all frames |
8992 | ** in the log were checkpointed. ^The [busy-handler callback] |
8993 | ** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode. |
8994 | ** ^On the other hand, passive mode might leave the checkpoint unfinished |
8995 | ** if there are concurrent readers or writers. |
8996 | ** |
8997 | ** <dt>SQLITE_CHECKPOINT_FULL<dd> |
8998 | ** ^This mode blocks (it invokes the |
8999 | ** [sqlite3_busy_handler|busy-handler callback]) until there is no |
9000 | ** database writer and all readers are reading from the most recent database |
9001 | ** snapshot. ^It then checkpoints all frames in the log file and syncs the |
9002 | ** database file. ^This mode blocks new database writers while it is pending, |
9003 | ** but new database readers are allowed to continue unimpeded. |
9004 | ** |
9005 | ** <dt>SQLITE_CHECKPOINT_RESTART<dd> |
9006 | ** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition |
9007 | ** that after checkpointing the log file it blocks (calls the |
9008 | ** [busy-handler callback]) |
9009 | ** until all readers are reading from the database file only. ^This ensures |
9010 | ** that the next writer will restart the log file from the beginning. |
9011 | ** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new |
9012 | ** database writer attempts while it is pending, but does not impede readers. |
9013 | ** |
9014 | ** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd> |
9015 | ** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the |
9016 | ** addition that it also truncates the log file to zero bytes just prior |
9017 | ** to a successful return. |
9018 | ** </dl> |
9019 | ** |
9020 | ** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in |
9021 | ** the log file or to -1 if the checkpoint could not run because |
9022 | ** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not |
9023 | ** NULL,then *pnCkpt is set to the total number of checkpointed frames in the |
9024 | ** log file (including any that were already checkpointed before the function |
9025 | ** was called) or to -1 if the checkpoint could not run due to an error or |
9026 | ** because the database is not in WAL mode. ^Note that upon successful |
9027 | ** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been |
9028 | ** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero. |
9029 | ** |
9030 | ** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If |
9031 | ** any other process is running a checkpoint operation at the same time, the |
9032 | ** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a |
9033 | ** busy-handler configured, it will not be invoked in this case. |
9034 | ** |
9035 | ** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the |
9036 | ** exclusive "writer" lock on the database file. ^If the writer lock cannot be |
9037 | ** obtained immediately, and a busy-handler is configured, it is invoked and |
9038 | ** the writer lock retried until either the busy-handler returns 0 or the lock |
9039 | ** is successfully obtained. ^The busy-handler is also invoked while waiting for |
9040 | ** database readers as described above. ^If the busy-handler returns 0 before |
9041 | ** the writer lock is obtained or while waiting for database readers, the |
9042 | ** checkpoint operation proceeds from that point in the same way as |
9043 | ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible |
9044 | ** without blocking any further. ^SQLITE_BUSY is returned in this case. |
9045 | ** |
9046 | ** ^If parameter zDb is NULL or points to a zero length string, then the |
9047 | ** specified operation is attempted on all WAL databases [attached] to |
9048 | ** [database connection] db. In this case the |
9049 | ** values written to output parameters *pnLog and *pnCkpt are undefined. ^If |
9050 | ** an SQLITE_BUSY error is encountered when processing one or more of the |
9051 | ** attached WAL databases, the operation is still attempted on any remaining |
9052 | ** attached databases and SQLITE_BUSY is returned at the end. ^If any other |
9053 | ** error occurs while processing an attached database, processing is abandoned |
9054 | ** and the error code is returned to the caller immediately. ^If no error |
9055 | ** (SQLITE_BUSY or otherwise) is encountered while processing the attached |
9056 | ** databases, SQLITE_OK is returned. |
9057 | ** |
9058 | ** ^If database zDb is the name of an attached database that is not in WAL |
9059 | ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If |
9060 | ** zDb is not NULL (or a zero length string) and is not the name of any |
9061 | ** attached database, SQLITE_ERROR is returned to the caller. |
9062 | ** |
9063 | ** ^Unless it returns SQLITE_MISUSE, |
9064 | ** the sqlite3_wal_checkpoint_v2() interface |
9065 | ** sets the error information that is queried by |
9066 | ** [sqlite3_errcode()] and [sqlite3_errmsg()]. |
9067 | ** |
9068 | ** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface |
9069 | ** from SQL. |
9070 | */ |
9071 | SQLITE_API int sqlite3_wal_checkpoint_v2( |
9072 | sqlite3 *db, /* Database handle */ |
9073 | const char *zDb, /* Name of attached database (or NULL) */ |
9074 | int eMode, /* SQLITE_CHECKPOINT_* value */ |
9075 | int *pnLog, /* OUT: Size of WAL log in frames */ |
9076 | int *pnCkpt /* OUT: Total number of frames checkpointed */ |
9077 | ); |
9078 | |
9079 | /* |
9080 | ** CAPI3REF: Checkpoint Mode Values |
9081 | ** KEYWORDS: {checkpoint mode} |
9082 | ** |
9083 | ** These constants define all valid values for the "checkpoint mode" passed |
9084 | ** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface. |
9085 | ** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the |
9086 | ** meaning of each of these checkpoint modes. |
9087 | */ |
9088 | #define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */ |
9089 | #define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */ |
9090 | #define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for for readers */ |
9091 | #define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */ |
9092 | |
9093 | /* |
9094 | ** CAPI3REF: Virtual Table Interface Configuration |
9095 | ** |
9096 | ** This function may be called by either the [xConnect] or [xCreate] method |
9097 | ** of a [virtual table] implementation to configure |
9098 | ** various facets of the virtual table interface. |
9099 | ** |
9100 | ** If this interface is invoked outside the context of an xConnect or |
9101 | ** xCreate virtual table method then the behavior is undefined. |
9102 | ** |
9103 | ** In the call sqlite3_vtab_config(D,C,...) the D parameter is the |
9104 | ** [database connection] in which the virtual table is being created and |
9105 | ** which is passed in as the first argument to the [xConnect] or [xCreate] |
9106 | ** method that is invoking sqlite3_vtab_config(). The C parameter is one |
9107 | ** of the [virtual table configuration options]. The presence and meaning |
9108 | ** of parameters after C depend on which [virtual table configuration option] |
9109 | ** is used. |
9110 | */ |
9111 | SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...); |
9112 | |
9113 | /* |
9114 | ** CAPI3REF: Virtual Table Configuration Options |
9115 | ** KEYWORDS: {virtual table configuration options} |
9116 | ** KEYWORDS: {virtual table configuration option} |
9117 | ** |
9118 | ** These macros define the various options to the |
9119 | ** [sqlite3_vtab_config()] interface that [virtual table] implementations |
9120 | ** can use to customize and optimize their behavior. |
9121 | ** |
9122 | ** <dl> |
9123 | ** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]] |
9124 | ** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT</dt> |
9125 | ** <dd>Calls of the form |
9126 | ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported, |
9127 | ** where X is an integer. If X is zero, then the [virtual table] whose |
9128 | ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not |
9129 | ** support constraints. In this configuration (which is the default) if |
9130 | ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire |
9131 | ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been |
9132 | ** specified as part of the users SQL statement, regardless of the actual |
9133 | ** ON CONFLICT mode specified. |
9134 | ** |
9135 | ** If X is non-zero, then the virtual table implementation guarantees |
9136 | ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before |
9137 | ** any modifications to internal or persistent data structures have been made. |
9138 | ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite |
9139 | ** is able to roll back a statement or database transaction, and abandon |
9140 | ** or continue processing the current SQL statement as appropriate. |
9141 | ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns |
9142 | ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode |
9143 | ** had been ABORT. |
9144 | ** |
9145 | ** Virtual table implementations that are required to handle OR REPLACE |
9146 | ** must do so within the [xUpdate] method. If a call to the |
9147 | ** [sqlite3_vtab_on_conflict()] function indicates that the current ON |
9148 | ** CONFLICT policy is REPLACE, the virtual table implementation should |
9149 | ** silently replace the appropriate rows within the xUpdate callback and |
9150 | ** return SQLITE_OK. Or, if this is not possible, it may return |
9151 | ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT |
9152 | ** constraint handling. |
9153 | ** </dd> |
9154 | ** |
9155 | ** [[SQLITE_VTAB_DIRECTONLY]]<dt>SQLITE_VTAB_DIRECTONLY</dt> |
9156 | ** <dd>Calls of the form |
9157 | ** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the |
9158 | ** the [xConnect] or [xCreate] methods of a [virtual table] implmentation |
9159 | ** prohibits that virtual table from being used from within triggers and |
9160 | ** views. |
9161 | ** </dd> |
9162 | ** |
9163 | ** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt> |
9164 | ** <dd>Calls of the form |
9165 | ** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the |
9166 | ** the [xConnect] or [xCreate] methods of a [virtual table] implmentation |
9167 | ** identify that virtual table as being safe to use from within triggers |
9168 | ** and views. Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the |
9169 | ** virtual table can do no serious harm even if it is controlled by a |
9170 | ** malicious hacker. Developers should avoid setting the SQLITE_VTAB_INNOCUOUS |
9171 | ** flag unless absolutely necessary. |
9172 | ** </dd> |
9173 | ** </dl> |
9174 | */ |
9175 | #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1 |
9176 | #define SQLITE_VTAB_INNOCUOUS 2 |
9177 | #define SQLITE_VTAB_DIRECTONLY 3 |
9178 | |
9179 | /* |
9180 | ** CAPI3REF: Determine The Virtual Table Conflict Policy |
9181 | ** |
9182 | ** This function may only be called from within a call to the [xUpdate] method |
9183 | ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The |
9184 | ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL], |
9185 | ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode |
9186 | ** of the SQL statement that triggered the call to the [xUpdate] method of the |
9187 | ** [virtual table]. |
9188 | */ |
9189 | SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *); |
9190 | |
9191 | /* |
9192 | ** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE |
9193 | ** |
9194 | ** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn] |
9195 | ** method of a [virtual table], then it returns true if and only if the |
9196 | ** column is being fetched as part of an UPDATE operation during which the |
9197 | ** column value will not change. Applications might use this to substitute |
9198 | ** a return value that is less expensive to compute and that the corresponding |
9199 | ** [xUpdate] method understands as a "no-change" value. |
9200 | ** |
9201 | ** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that |
9202 | ** the column is not changed by the UPDATE statement, then the xColumn |
9203 | ** method can optionally return without setting a result, without calling |
9204 | ** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces]. |
9205 | ** In that case, [sqlite3_value_nochange(X)] will return true for the |
9206 | ** same column in the [xUpdate] method. |
9207 | */ |
9208 | SQLITE_API int sqlite3_vtab_nochange(sqlite3_context*); |
9209 | |
9210 | /* |
9211 | ** CAPI3REF: Determine The Collation For a Virtual Table Constraint |
9212 | ** |
9213 | ** This function may only be called from within a call to the [xBestIndex] |
9214 | ** method of a [virtual table]. |
9215 | ** |
9216 | ** The first argument must be the sqlite3_index_info object that is the |
9217 | ** first parameter to the xBestIndex() method. The second argument must be |
9218 | ** an index into the aConstraint[] array belonging to the sqlite3_index_info |
9219 | ** structure passed to xBestIndex. This function returns a pointer to a buffer |
9220 | ** containing the name of the collation sequence for the corresponding |
9221 | ** constraint. |
9222 | */ |
9223 | SQLITE_API SQLITE_EXPERIMENTAL const char *sqlite3_vtab_collation(sqlite3_index_info*,int); |
9224 | |
9225 | /* |
9226 | ** CAPI3REF: Conflict resolution modes |
9227 | ** KEYWORDS: {conflict resolution mode} |
9228 | ** |
9229 | ** These constants are returned by [sqlite3_vtab_on_conflict()] to |
9230 | ** inform a [virtual table] implementation what the [ON CONFLICT] mode |
9231 | ** is for the SQL statement being evaluated. |
9232 | ** |
9233 | ** Note that the [SQLITE_IGNORE] constant is also used as a potential |
9234 | ** return value from the [sqlite3_set_authorizer()] callback and that |
9235 | ** [SQLITE_ABORT] is also a [result code]. |
9236 | */ |
9237 | #define SQLITE_ROLLBACK 1 |
9238 | /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */ |
9239 | #define SQLITE_FAIL 3 |
9240 | /* #define SQLITE_ABORT 4 // Also an error code */ |
9241 | #define SQLITE_REPLACE 5 |
9242 | |
9243 | /* |
9244 | ** CAPI3REF: Prepared Statement Scan Status Opcodes |
9245 | ** KEYWORDS: {scanstatus options} |
9246 | ** |
9247 | ** The following constants can be used for the T parameter to the |
9248 | ** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a |
9249 | ** different metric for sqlite3_stmt_scanstatus() to return. |
9250 | ** |
9251 | ** When the value returned to V is a string, space to hold that string is |
9252 | ** managed by the prepared statement S and will be automatically freed when |
9253 | ** S is finalized. |
9254 | ** |
9255 | ** <dl> |
9256 | ** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt> |
9257 | ** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be |
9258 | ** set to the total number of times that the X-th loop has run.</dd> |
9259 | ** |
9260 | ** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt> |
9261 | ** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set |
9262 | ** to the total number of rows examined by all iterations of the X-th loop.</dd> |
9263 | ** |
9264 | ** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt> |
9265 | ** <dd>^The "double" variable pointed to by the V parameter will be set to the |
9266 | ** query planner's estimate for the average number of rows output from each |
9267 | ** iteration of the X-th loop. If the query planner's estimates was accurate, |
9268 | ** then this value will approximate the quotient NVISIT/NLOOP and the |
9269 | ** product of this value for all prior loops with the same SELECTID will |
9270 | ** be the NLOOP value for the current loop. |
9271 | ** |
9272 | ** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt> |
9273 | ** <dd>^The "const char *" variable pointed to by the V parameter will be set |
9274 | ** to a zero-terminated UTF-8 string containing the name of the index or table |
9275 | ** used for the X-th loop. |
9276 | ** |
9277 | ** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt> |
9278 | ** <dd>^The "const char *" variable pointed to by the V parameter will be set |
9279 | ** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN] |
9280 | ** description for the X-th loop. |
9281 | ** |
9282 | ** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt> |
9283 | ** <dd>^The "int" variable pointed to by the V parameter will be set to the |
9284 | ** "select-id" for the X-th loop. The select-id identifies which query or |
9285 | ** subquery the loop is part of. The main query has a select-id of zero. |
9286 | ** The select-id is the same value as is output in the first column |
9287 | ** of an [EXPLAIN QUERY PLAN] query. |
9288 | ** </dl> |
9289 | */ |
9290 | #define SQLITE_SCANSTAT_NLOOP 0 |
9291 | #define SQLITE_SCANSTAT_NVISIT 1 |
9292 | #define SQLITE_SCANSTAT_EST 2 |
9293 | #define SQLITE_SCANSTAT_NAME 3 |
9294 | #define SQLITE_SCANSTAT_EXPLAIN 4 |
9295 | #define SQLITE_SCANSTAT_SELECTID 5 |
9296 | |
9297 | /* |
9298 | ** CAPI3REF: Prepared Statement Scan Status |
9299 | ** METHOD: sqlite3_stmt |
9300 | ** |
9301 | ** This interface returns information about the predicted and measured |
9302 | ** performance for pStmt. Advanced applications can use this |
9303 | ** interface to compare the predicted and the measured performance and |
9304 | ** issue warnings and/or rerun [ANALYZE] if discrepancies are found. |
9305 | ** |
9306 | ** Since this interface is expected to be rarely used, it is only |
9307 | ** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS] |
9308 | ** compile-time option. |
9309 | ** |
9310 | ** The "iScanStatusOp" parameter determines which status information to return. |
9311 | ** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior |
9312 | ** of this interface is undefined. |
9313 | ** ^The requested measurement is written into a variable pointed to by |
9314 | ** the "pOut" parameter. |
9315 | ** Parameter "idx" identifies the specific loop to retrieve statistics for. |
9316 | ** Loops are numbered starting from zero. ^If idx is out of range - less than |
9317 | ** zero or greater than or equal to the total number of loops used to implement |
9318 | ** the statement - a non-zero value is returned and the variable that pOut |
9319 | ** points to is unchanged. |
9320 | ** |
9321 | ** ^Statistics might not be available for all loops in all statements. ^In cases |
9322 | ** where there exist loops with no available statistics, this function behaves |
9323 | ** as if the loop did not exist - it returns non-zero and leave the variable |
9324 | ** that pOut points to unchanged. |
9325 | ** |
9326 | ** See also: [sqlite3_stmt_scanstatus_reset()] |
9327 | */ |
9328 | SQLITE_API int sqlite3_stmt_scanstatus( |
9329 | sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ |
9330 | int idx, /* Index of loop to report on */ |
9331 | int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ |
9332 | void *pOut /* Result written here */ |
9333 | ); |
9334 | |
9335 | /* |
9336 | ** CAPI3REF: Zero Scan-Status Counters |
9337 | ** METHOD: sqlite3_stmt |
9338 | ** |
9339 | ** ^Zero all [sqlite3_stmt_scanstatus()] related event counters. |
9340 | ** |
9341 | ** This API is only available if the library is built with pre-processor |
9342 | ** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. |
9343 | */ |
9344 | SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); |
9345 | |
9346 | /* |
9347 | ** CAPI3REF: Flush caches to disk mid-transaction |
9348 | ** |
9349 | ** ^If a write-transaction is open on [database connection] D when the |
9350 | ** [sqlite3_db_cacheflush(D)] interface invoked, any dirty |
9351 | ** pages in the pager-cache that are not currently in use are written out |
9352 | ** to disk. A dirty page may be in use if a database cursor created by an |
9353 | ** active SQL statement is reading from it, or if it is page 1 of a database |
9354 | ** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)] |
9355 | ** interface flushes caches for all schemas - "main", "temp", and |
9356 | ** any [attached] databases. |
9357 | ** |
9358 | ** ^If this function needs to obtain extra database locks before dirty pages |
9359 | ** can be flushed to disk, it does so. ^If those locks cannot be obtained |
9360 | ** immediately and there is a busy-handler callback configured, it is invoked |
9361 | ** in the usual manner. ^If the required lock still cannot be obtained, then |
9362 | ** the database is skipped and an attempt made to flush any dirty pages |
9363 | ** belonging to the next (if any) database. ^If any databases are skipped |
9364 | ** because locks cannot be obtained, but no other error occurs, this |
9365 | ** function returns SQLITE_BUSY. |
9366 | ** |
9367 | ** ^If any other error occurs while flushing dirty pages to disk (for |
9368 | ** example an IO error or out-of-memory condition), then processing is |
9369 | ** abandoned and an SQLite [error code] is returned to the caller immediately. |
9370 | ** |
9371 | ** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK. |
9372 | ** |
9373 | ** ^This function does not set the database handle error code or message |
9374 | ** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions. |
9375 | */ |
9376 | SQLITE_API int sqlite3_db_cacheflush(sqlite3*); |
9377 | |
9378 | /* |
9379 | ** CAPI3REF: The pre-update hook. |
9380 | ** |
9381 | ** ^These interfaces are only available if SQLite is compiled using the |
9382 | ** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option. |
9383 | ** |
9384 | ** ^The [sqlite3_preupdate_hook()] interface registers a callback function |
9385 | ** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation |
9386 | ** on a database table. |
9387 | ** ^At most one preupdate hook may be registered at a time on a single |
9388 | ** [database connection]; each call to [sqlite3_preupdate_hook()] overrides |
9389 | ** the previous setting. |
9390 | ** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()] |
9391 | ** with a NULL pointer as the second parameter. |
9392 | ** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as |
9393 | ** the first parameter to callbacks. |
9394 | ** |
9395 | ** ^The preupdate hook only fires for changes to real database tables; the |
9396 | ** preupdate hook is not invoked for changes to [virtual tables] or to |
9397 | ** system tables like sqlite_sequence or sqlite_stat1. |
9398 | ** |
9399 | ** ^The second parameter to the preupdate callback is a pointer to |
9400 | ** the [database connection] that registered the preupdate hook. |
9401 | ** ^The third parameter to the preupdate callback is one of the constants |
9402 | ** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the |
9403 | ** kind of update operation that is about to occur. |
9404 | ** ^(The fourth parameter to the preupdate callback is the name of the |
9405 | ** database within the database connection that is being modified. This |
9406 | ** will be "main" for the main database or "temp" for TEMP tables or |
9407 | ** the name given after the AS keyword in the [ATTACH] statement for attached |
9408 | ** databases.)^ |
9409 | ** ^The fifth parameter to the preupdate callback is the name of the |
9410 | ** table that is being modified. |
9411 | ** |
9412 | ** For an UPDATE or DELETE operation on a [rowid table], the sixth |
9413 | ** parameter passed to the preupdate callback is the initial [rowid] of the |
9414 | ** row being modified or deleted. For an INSERT operation on a rowid table, |
9415 | ** or any operation on a WITHOUT ROWID table, the value of the sixth |
9416 | ** parameter is undefined. For an INSERT or UPDATE on a rowid table the |
9417 | ** seventh parameter is the final rowid value of the row being inserted |
9418 | ** or updated. The value of the seventh parameter passed to the callback |
9419 | ** function is not defined for operations on WITHOUT ROWID tables, or for |
9420 | ** INSERT operations on rowid tables. |
9421 | ** |
9422 | ** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()], |
9423 | ** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces |
9424 | ** provide additional information about a preupdate event. These routines |
9425 | ** may only be called from within a preupdate callback. Invoking any of |
9426 | ** these routines from outside of a preupdate callback or with a |
9427 | ** [database connection] pointer that is different from the one supplied |
9428 | ** to the preupdate callback results in undefined and probably undesirable |
9429 | ** behavior. |
9430 | ** |
9431 | ** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns |
9432 | ** in the row that is being inserted, updated, or deleted. |
9433 | ** |
9434 | ** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to |
9435 | ** a [protected sqlite3_value] that contains the value of the Nth column of |
9436 | ** the table row before it is updated. The N parameter must be between 0 |
9437 | ** and one less than the number of columns or the behavior will be |
9438 | ** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE |
9439 | ** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the |
9440 | ** behavior is undefined. The [sqlite3_value] that P points to |
9441 | ** will be destroyed when the preupdate callback returns. |
9442 | ** |
9443 | ** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to |
9444 | ** a [protected sqlite3_value] that contains the value of the Nth column of |
9445 | ** the table row after it is updated. The N parameter must be between 0 |
9446 | ** and one less than the number of columns or the behavior will be |
9447 | ** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE |
9448 | ** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the |
9449 | ** behavior is undefined. The [sqlite3_value] that P points to |
9450 | ** will be destroyed when the preupdate callback returns. |
9451 | ** |
9452 | ** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate |
9453 | ** callback was invoked as a result of a direct insert, update, or delete |
9454 | ** operation; or 1 for inserts, updates, or deletes invoked by top-level |
9455 | ** triggers; or 2 for changes resulting from triggers called by top-level |
9456 | ** triggers; and so forth. |
9457 | ** |
9458 | ** See also: [sqlite3_update_hook()] |
9459 | */ |
9460 | #if defined(SQLITE_ENABLE_PREUPDATE_HOOK) |
9461 | SQLITE_API void *sqlite3_preupdate_hook( |
9462 | sqlite3 *db, |
9463 | void(*xPreUpdate)( |
9464 | void *pCtx, /* Copy of third arg to preupdate_hook() */ |
9465 | sqlite3 *db, /* Database handle */ |
9466 | int op, /* SQLITE_UPDATE, DELETE or INSERT */ |
9467 | char const *zDb, /* Database name */ |
9468 | char const *zName, /* Table name */ |
9469 | sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */ |
9470 | sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */ |
9471 | ), |
9472 | void* |
9473 | ); |
9474 | SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **); |
9475 | SQLITE_API int sqlite3_preupdate_count(sqlite3 *); |
9476 | SQLITE_API int sqlite3_preupdate_depth(sqlite3 *); |
9477 | SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **); |
9478 | #endif |
9479 | |
9480 | /* |
9481 | ** CAPI3REF: Low-level system error code |
9482 | ** |
9483 | ** ^Attempt to return the underlying operating system error code or error |
9484 | ** number that caused the most recent I/O error or failure to open a file. |
9485 | ** The return value is OS-dependent. For example, on unix systems, after |
9486 | ** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be |
9487 | ** called to get back the underlying "errno" that caused the problem, such |
9488 | ** as ENOSPC, EAUTH, EISDIR, and so forth. |
9489 | */ |
9490 | SQLITE_API int sqlite3_system_errno(sqlite3*); |
9491 | |
9492 | /* |
9493 | ** CAPI3REF: Database Snapshot |
9494 | ** KEYWORDS: {snapshot} {sqlite3_snapshot} |
9495 | ** |
9496 | ** An instance of the snapshot object records the state of a [WAL mode] |
9497 | ** database for some specific point in history. |
9498 | ** |
9499 | ** In [WAL mode], multiple [database connections] that are open on the |
9500 | ** same database file can each be reading a different historical version |
9501 | ** of the database file. When a [database connection] begins a read |
9502 | ** transaction, that connection sees an unchanging copy of the database |
9503 | ** as it existed for the point in time when the transaction first started. |
9504 | ** Subsequent changes to the database from other connections are not seen |
9505 | ** by the reader until a new read transaction is started. |
9506 | ** |
9507 | ** The sqlite3_snapshot object records state information about an historical |
9508 | ** version of the database file so that it is possible to later open a new read |
9509 | ** transaction that sees that historical version of the database rather than |
9510 | ** the most recent version. |
9511 | */ |
9512 | typedef struct sqlite3_snapshot { |
9513 | unsigned char hidden[48]; |
9514 | } sqlite3_snapshot; |
9515 | |
9516 | /* |
9517 | ** CAPI3REF: Record A Database Snapshot |
9518 | ** CONSTRUCTOR: sqlite3_snapshot |
9519 | ** |
9520 | ** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a |
9521 | ** new [sqlite3_snapshot] object that records the current state of |
9522 | ** schema S in database connection D. ^On success, the |
9523 | ** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly |
9524 | ** created [sqlite3_snapshot] object into *P and returns SQLITE_OK. |
9525 | ** If there is not already a read-transaction open on schema S when |
9526 | ** this function is called, one is opened automatically. |
9527 | ** |
9528 | ** The following must be true for this function to succeed. If any of |
9529 | ** the following statements are false when sqlite3_snapshot_get() is |
9530 | ** called, SQLITE_ERROR is returned. The final value of *P is undefined |
9531 | ** in this case. |
9532 | ** |
9533 | ** <ul> |
9534 | ** <li> The database handle must not be in [autocommit mode]. |
9535 | ** |
9536 | ** <li> Schema S of [database connection] D must be a [WAL mode] database. |
9537 | ** |
9538 | ** <li> There must not be a write transaction open on schema S of database |
9539 | ** connection D. |
9540 | ** |
9541 | ** <li> One or more transactions must have been written to the current wal |
9542 | ** file since it was created on disk (by any connection). This means |
9543 | ** that a snapshot cannot be taken on a wal mode database with no wal |
9544 | ** file immediately after it is first opened. At least one transaction |
9545 | ** must be written to it first. |
9546 | ** </ul> |
9547 | ** |
9548 | ** This function may also return SQLITE_NOMEM. If it is called with the |
9549 | ** database handle in autocommit mode but fails for some other reason, |
9550 | ** whether or not a read transaction is opened on schema S is undefined. |
9551 | ** |
9552 | ** The [sqlite3_snapshot] object returned from a successful call to |
9553 | ** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()] |
9554 | ** to avoid a memory leak. |
9555 | ** |
9556 | ** The [sqlite3_snapshot_get()] interface is only available when the |
9557 | ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. |
9558 | */ |
9559 | SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get( |
9560 | sqlite3 *db, |
9561 | const char *zSchema, |
9562 | sqlite3_snapshot **ppSnapshot |
9563 | ); |
9564 | |
9565 | /* |
9566 | ** CAPI3REF: Start a read transaction on an historical snapshot |
9567 | ** METHOD: sqlite3_snapshot |
9568 | ** |
9569 | ** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read |
9570 | ** transaction or upgrades an existing one for schema S of |
9571 | ** [database connection] D such that the read transaction refers to |
9572 | ** historical [snapshot] P, rather than the most recent change to the |
9573 | ** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK |
9574 | ** on success or an appropriate [error code] if it fails. |
9575 | ** |
9576 | ** ^In order to succeed, the database connection must not be in |
9577 | ** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there |
9578 | ** is already a read transaction open on schema S, then the database handle |
9579 | ** must have no active statements (SELECT statements that have been passed |
9580 | ** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()). |
9581 | ** SQLITE_ERROR is returned if either of these conditions is violated, or |
9582 | ** if schema S does not exist, or if the snapshot object is invalid. |
9583 | ** |
9584 | ** ^A call to sqlite3_snapshot_open() will fail to open if the specified |
9585 | ** snapshot has been overwritten by a [checkpoint]. In this case |
9586 | ** SQLITE_ERROR_SNAPSHOT is returned. |
9587 | ** |
9588 | ** If there is already a read transaction open when this function is |
9589 | ** invoked, then the same read transaction remains open (on the same |
9590 | ** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT |
9591 | ** is returned. If another error code - for example SQLITE_PROTOCOL or an |
9592 | ** SQLITE_IOERR error code - is returned, then the final state of the |
9593 | ** read transaction is undefined. If SQLITE_OK is returned, then the |
9594 | ** read transaction is now open on database snapshot P. |
9595 | ** |
9596 | ** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the |
9597 | ** database connection D does not know that the database file for |
9598 | ** schema S is in [WAL mode]. A database connection might not know |
9599 | ** that the database file is in [WAL mode] if there has been no prior |
9600 | ** I/O on that database connection, or if the database entered [WAL mode] |
9601 | ** after the most recent I/O on the database connection.)^ |
9602 | ** (Hint: Run "[PRAGMA application_id]" against a newly opened |
9603 | ** database connection in order to make it ready to use snapshots.) |
9604 | ** |
9605 | ** The [sqlite3_snapshot_open()] interface is only available when the |
9606 | ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. |
9607 | */ |
9608 | SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open( |
9609 | sqlite3 *db, |
9610 | const char *zSchema, |
9611 | sqlite3_snapshot *pSnapshot |
9612 | ); |
9613 | |
9614 | /* |
9615 | ** CAPI3REF: Destroy a snapshot |
9616 | ** DESTRUCTOR: sqlite3_snapshot |
9617 | ** |
9618 | ** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P. |
9619 | ** The application must eventually free every [sqlite3_snapshot] object |
9620 | ** using this routine to avoid a memory leak. |
9621 | ** |
9622 | ** The [sqlite3_snapshot_free()] interface is only available when the |
9623 | ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. |
9624 | */ |
9625 | SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*); |
9626 | |
9627 | /* |
9628 | ** CAPI3REF: Compare the ages of two snapshot handles. |
9629 | ** METHOD: sqlite3_snapshot |
9630 | ** |
9631 | ** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages |
9632 | ** of two valid snapshot handles. |
9633 | ** |
9634 | ** If the two snapshot handles are not associated with the same database |
9635 | ** file, the result of the comparison is undefined. |
9636 | ** |
9637 | ** Additionally, the result of the comparison is only valid if both of the |
9638 | ** snapshot handles were obtained by calling sqlite3_snapshot_get() since the |
9639 | ** last time the wal file was deleted. The wal file is deleted when the |
9640 | ** database is changed back to rollback mode or when the number of database |
9641 | ** clients drops to zero. If either snapshot handle was obtained before the |
9642 | ** wal file was last deleted, the value returned by this function |
9643 | ** is undefined. |
9644 | ** |
9645 | ** Otherwise, this API returns a negative value if P1 refers to an older |
9646 | ** snapshot than P2, zero if the two handles refer to the same database |
9647 | ** snapshot, and a positive value if P1 is a newer snapshot than P2. |
9648 | ** |
9649 | ** This interface is only available if SQLite is compiled with the |
9650 | ** [SQLITE_ENABLE_SNAPSHOT] option. |
9651 | */ |
9652 | SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp( |
9653 | sqlite3_snapshot *p1, |
9654 | sqlite3_snapshot *p2 |
9655 | ); |
9656 | |
9657 | /* |
9658 | ** CAPI3REF: Recover snapshots from a wal file |
9659 | ** METHOD: sqlite3_snapshot |
9660 | ** |
9661 | ** If a [WAL file] remains on disk after all database connections close |
9662 | ** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control] |
9663 | ** or because the last process to have the database opened exited without |
9664 | ** calling [sqlite3_close()]) and a new connection is subsequently opened |
9665 | ** on that database and [WAL file], the [sqlite3_snapshot_open()] interface |
9666 | ** will only be able to open the last transaction added to the WAL file |
9667 | ** even though the WAL file contains other valid transactions. |
9668 | ** |
9669 | ** This function attempts to scan the WAL file associated with database zDb |
9670 | ** of database handle db and make all valid snapshots available to |
9671 | ** sqlite3_snapshot_open(). It is an error if there is already a read |
9672 | ** transaction open on the database, or if the database is not a WAL mode |
9673 | ** database. |
9674 | ** |
9675 | ** SQLITE_OK is returned if successful, or an SQLite error code otherwise. |
9676 | ** |
9677 | ** This interface is only available if SQLite is compiled with the |
9678 | ** [SQLITE_ENABLE_SNAPSHOT] option. |
9679 | */ |
9680 | SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb); |
9681 | |
9682 | /* |
9683 | ** CAPI3REF: Serialize a database |
9684 | ** |
9685 | ** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory |
9686 | ** that is a serialization of the S database on [database connection] D. |
9687 | ** If P is not a NULL pointer, then the size of the database in bytes |
9688 | ** is written into *P. |
9689 | ** |
9690 | ** For an ordinary on-disk database file, the serialization is just a |
9691 | ** copy of the disk file. For an in-memory database or a "TEMP" database, |
9692 | ** the serialization is the same sequence of bytes which would be written |
9693 | ** to disk if that database where backed up to disk. |
9694 | ** |
9695 | ** The usual case is that sqlite3_serialize() copies the serialization of |
9696 | ** the database into memory obtained from [sqlite3_malloc64()] and returns |
9697 | ** a pointer to that memory. The caller is responsible for freeing the |
9698 | ** returned value to avoid a memory leak. However, if the F argument |
9699 | ** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations |
9700 | ** are made, and the sqlite3_serialize() function will return a pointer |
9701 | ** to the contiguous memory representation of the database that SQLite |
9702 | ** is currently using for that database, or NULL if the no such contiguous |
9703 | ** memory representation of the database exists. A contiguous memory |
9704 | ** representation of the database will usually only exist if there has |
9705 | ** been a prior call to [sqlite3_deserialize(D,S,...)] with the same |
9706 | ** values of D and S. |
9707 | ** The size of the database is written into *P even if the |
9708 | ** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy |
9709 | ** of the database exists. |
9710 | ** |
9711 | ** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the |
9712 | ** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory |
9713 | ** allocation error occurs. |
9714 | ** |
9715 | ** This interface is only available if SQLite is compiled with the |
9716 | ** [SQLITE_ENABLE_DESERIALIZE] option. |
9717 | */ |
9718 | SQLITE_API unsigned char *sqlite3_serialize( |
9719 | sqlite3 *db, /* The database connection */ |
9720 | const char *zSchema, /* Which DB to serialize. ex: "main", "temp", ... */ |
9721 | sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */ |
9722 | unsigned int mFlags /* Zero or more SQLITE_SERIALIZE_* flags */ |
9723 | ); |
9724 | |
9725 | /* |
9726 | ** CAPI3REF: Flags for sqlite3_serialize |
9727 | ** |
9728 | ** Zero or more of the following constants can be OR-ed together for |
9729 | ** the F argument to [sqlite3_serialize(D,S,P,F)]. |
9730 | ** |
9731 | ** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return |
9732 | ** a pointer to contiguous in-memory database that it is currently using, |
9733 | ** without making a copy of the database. If SQLite is not currently using |
9734 | ** a contiguous in-memory database, then this option causes |
9735 | ** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be |
9736 | ** using a contiguous in-memory database if it has been initialized by a |
9737 | ** prior call to [sqlite3_deserialize()]. |
9738 | */ |
9739 | #define SQLITE_SERIALIZE_NOCOPY 0x001 /* Do no memory allocations */ |
9740 | |
9741 | /* |
9742 | ** CAPI3REF: Deserialize a database |
9743 | ** |
9744 | ** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the |
9745 | ** [database connection] D to disconnect from database S and then |
9746 | ** reopen S as an in-memory database based on the serialization contained |
9747 | ** in P. The serialized database P is N bytes in size. M is the size of |
9748 | ** the buffer P, which might be larger than N. If M is larger than N, and |
9749 | ** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is |
9750 | ** permitted to add content to the in-memory database as long as the total |
9751 | ** size does not exceed M bytes. |
9752 | ** |
9753 | ** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will |
9754 | ** invoke sqlite3_free() on the serialization buffer when the database |
9755 | ** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then |
9756 | ** SQLite will try to increase the buffer size using sqlite3_realloc64() |
9757 | ** if writes on the database cause it to grow larger than M bytes. |
9758 | ** |
9759 | ** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the |
9760 | ** database is currently in a read transaction or is involved in a backup |
9761 | ** operation. |
9762 | ** |
9763 | ** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the |
9764 | ** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then |
9765 | ** [sqlite3_free()] is invoked on argument P prior to returning. |
9766 | ** |
9767 | ** This interface is only available if SQLite is compiled with the |
9768 | ** [SQLITE_ENABLE_DESERIALIZE] option. |
9769 | */ |
9770 | SQLITE_API int sqlite3_deserialize( |
9771 | sqlite3 *db, /* The database connection */ |
9772 | const char *zSchema, /* Which DB to reopen with the deserialization */ |
9773 | unsigned char *pData, /* The serialized database content */ |
9774 | sqlite3_int64 szDb, /* Number bytes in the deserialization */ |
9775 | sqlite3_int64 szBuf, /* Total size of buffer pData[] */ |
9776 | unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */ |
9777 | ); |
9778 | |
9779 | /* |
9780 | ** CAPI3REF: Flags for sqlite3_deserialize() |
9781 | ** |
9782 | ** The following are allowed values for 6th argument (the F argument) to |
9783 | ** the [sqlite3_deserialize(D,S,P,N,M,F)] interface. |
9784 | ** |
9785 | ** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization |
9786 | ** in the P argument is held in memory obtained from [sqlite3_malloc64()] |
9787 | ** and that SQLite should take ownership of this memory and automatically |
9788 | ** free it when it has finished using it. Without this flag, the caller |
9789 | ** is responsible for freeing any dynamically allocated memory. |
9790 | ** |
9791 | ** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to |
9792 | ** grow the size of the database using calls to [sqlite3_realloc64()]. This |
9793 | ** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used. |
9794 | ** Without this flag, the deserialized database cannot increase in size beyond |
9795 | ** the number of bytes specified by the M parameter. |
9796 | ** |
9797 | ** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database |
9798 | ** should be treated as read-only. |
9799 | */ |
9800 | #define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */ |
9801 | #define SQLITE_DESERIALIZE_RESIZEABLE 2 /* Resize using sqlite3_realloc64() */ |
9802 | #define SQLITE_DESERIALIZE_READONLY 4 /* Database is read-only */ |
9803 | |
9804 | /* |
9805 | ** Undo the hack that converts floating point types to integer for |
9806 | ** builds on processors without floating point support. |
9807 | */ |
9808 | #ifdef SQLITE_OMIT_FLOATING_POINT |
9809 | # undef double |
9810 | #endif |
9811 | |
9812 | #ifdef __cplusplus |
9813 | } /* End of the 'extern "C"' block */ |
9814 | #endif |
9815 | #endif /* SQLITE3_H */ |
9816 | |
9817 | /******** Begin file sqlite3rtree.h *********/ |
9818 | /* |
9819 | ** 2010 August 30 |
9820 | ** |
9821 | ** The author disclaims copyright to this source code. In place of |
9822 | ** a legal notice, here is a blessing: |
9823 | ** |
9824 | ** May you do good and not evil. |
9825 | ** May you find forgiveness for yourself and forgive others. |
9826 | ** May you share freely, never taking more than you give. |
9827 | ** |
9828 | ************************************************************************* |
9829 | */ |
9830 | |
9831 | #ifndef _SQLITE3RTREE_H_ |
9832 | #define _SQLITE3RTREE_H_ |
9833 | |
9834 | |
9835 | #ifdef __cplusplus |
9836 | extern "C" { |
9837 | #endif |
9838 | |
9839 | typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry; |
9840 | typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info; |
9841 | |
9842 | /* The double-precision datatype used by RTree depends on the |
9843 | ** SQLITE_RTREE_INT_ONLY compile-time option. |
9844 | */ |
9845 | #ifdef SQLITE_RTREE_INT_ONLY |
9846 | typedef sqlite3_int64 sqlite3_rtree_dbl; |
9847 | #else |
9848 | typedef double sqlite3_rtree_dbl; |
9849 | #endif |
9850 | |
9851 | /* |
9852 | ** Register a geometry callback named zGeom that can be used as part of an |
9853 | ** R-Tree geometry query as follows: |
9854 | ** |
9855 | ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...) |
9856 | */ |
9857 | SQLITE_API int sqlite3_rtree_geometry_callback( |
9858 | sqlite3 *db, |
9859 | const char *zGeom, |
9860 | int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*), |
9861 | void *pContext |
9862 | ); |
9863 | |
9864 | |
9865 | /* |
9866 | ** A pointer to a structure of the following type is passed as the first |
9867 | ** argument to callbacks registered using rtree_geometry_callback(). |
9868 | */ |
9869 | struct sqlite3_rtree_geometry { |
9870 | void *pContext; /* Copy of pContext passed to s_r_g_c() */ |
9871 | int nParam; /* Size of array aParam[] */ |
9872 | sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */ |
9873 | void *pUser; /* Callback implementation user data */ |
9874 | void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */ |
9875 | }; |
9876 | |
9877 | /* |
9878 | ** Register a 2nd-generation geometry callback named zScore that can be |
9879 | ** used as part of an R-Tree geometry query as follows: |
9880 | ** |
9881 | ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...) |
9882 | */ |
9883 | SQLITE_API int sqlite3_rtree_query_callback( |
9884 | sqlite3 *db, |
9885 | const char *zQueryFunc, |
9886 | int (*xQueryFunc)(sqlite3_rtree_query_info*), |
9887 | void *pContext, |
9888 | void (*xDestructor)(void*) |
9889 | ); |
9890 | |
9891 | |
9892 | /* |
9893 | ** A pointer to a structure of the following type is passed as the |
9894 | ** argument to scored geometry callback registered using |
9895 | ** sqlite3_rtree_query_callback(). |
9896 | ** |
9897 | ** Note that the first 5 fields of this structure are identical to |
9898 | ** sqlite3_rtree_geometry. This structure is a subclass of |
9899 | ** sqlite3_rtree_geometry. |
9900 | */ |
9901 | struct sqlite3_rtree_query_info { |
9902 | void *pContext; /* pContext from when function registered */ |
9903 | int nParam; /* Number of function parameters */ |
9904 | sqlite3_rtree_dbl *aParam; /* value of function parameters */ |
9905 | void *pUser; /* callback can use this, if desired */ |
9906 | void (*xDelUser)(void*); /* function to free pUser */ |
9907 | sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */ |
9908 | unsigned int *anQueue; /* Number of pending entries in the queue */ |
9909 | int nCoord; /* Number of coordinates */ |
9910 | int iLevel; /* Level of current node or entry */ |
9911 | int mxLevel; /* The largest iLevel value in the tree */ |
9912 | sqlite3_int64 iRowid; /* Rowid for current entry */ |
9913 | sqlite3_rtree_dbl rParentScore; /* Score of parent node */ |
9914 | int eParentWithin; /* Visibility of parent node */ |
9915 | int eWithin; /* OUT: Visibility */ |
9916 | sqlite3_rtree_dbl rScore; /* OUT: Write the score here */ |
9917 | /* The following fields are only available in 3.8.11 and later */ |
9918 | sqlite3_value **apSqlParam; /* Original SQL values of parameters */ |
9919 | }; |
9920 | |
9921 | /* |
9922 | ** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin. |
9923 | */ |
9924 | #define NOT_WITHIN 0 /* Object completely outside of query region */ |
9925 | #define PARTLY_WITHIN 1 /* Object partially overlaps query region */ |
9926 | #define FULLY_WITHIN 2 /* Object fully contained within query region */ |
9927 | |
9928 | |
9929 | #ifdef __cplusplus |
9930 | } /* end of the 'extern "C"' block */ |
9931 | #endif |
9932 | |
9933 | #endif /* ifndef _SQLITE3RTREE_H_ */ |
9934 | |
9935 | /******** End of sqlite3rtree.h *********/ |
9936 | /******** Begin file sqlite3session.h *********/ |
9937 | |
9938 | #if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) |
9939 | #define __SQLITESESSION_H_ 1 |
9940 | |
9941 | /* |
9942 | ** Make sure we can call this stuff from C++. |
9943 | */ |
9944 | #ifdef __cplusplus |
9945 | extern "C" { |
9946 | #endif |
9947 | |
9948 | |
9949 | /* |
9950 | ** CAPI3REF: Session Object Handle |
9951 | ** |
9952 | ** An instance of this object is a [session] that can be used to |
9953 | ** record changes to a database. |
9954 | */ |
9955 | typedef struct sqlite3_session sqlite3_session; |
9956 | |
9957 | /* |
9958 | ** CAPI3REF: Changeset Iterator Handle |
9959 | ** |
9960 | ** An instance of this object acts as a cursor for iterating |
9961 | ** over the elements of a [changeset] or [patchset]. |
9962 | */ |
9963 | typedef struct sqlite3_changeset_iter sqlite3_changeset_iter; |
9964 | |
9965 | /* |
9966 | ** CAPI3REF: Create A New Session Object |
9967 | ** CONSTRUCTOR: sqlite3_session |
9968 | ** |
9969 | ** Create a new session object attached to database handle db. If successful, |
9970 | ** a pointer to the new object is written to *ppSession and SQLITE_OK is |
9971 | ** returned. If an error occurs, *ppSession is set to NULL and an SQLite |
9972 | ** error code (e.g. SQLITE_NOMEM) is returned. |
9973 | ** |
9974 | ** It is possible to create multiple session objects attached to a single |
9975 | ** database handle. |
9976 | ** |
9977 | ** Session objects created using this function should be deleted using the |
9978 | ** [sqlite3session_delete()] function before the database handle that they |
9979 | ** are attached to is itself closed. If the database handle is closed before |
9980 | ** the session object is deleted, then the results of calling any session |
9981 | ** module function, including [sqlite3session_delete()] on the session object |
9982 | ** are undefined. |
9983 | ** |
9984 | ** Because the session module uses the [sqlite3_preupdate_hook()] API, it |
9985 | ** is not possible for an application to register a pre-update hook on a |
9986 | ** database handle that has one or more session objects attached. Nor is |
9987 | ** it possible to create a session object attached to a database handle for |
9988 | ** which a pre-update hook is already defined. The results of attempting |
9989 | ** either of these things are undefined. |
9990 | ** |
9991 | ** The session object will be used to create changesets for tables in |
9992 | ** database zDb, where zDb is either "main", or "temp", or the name of an |
9993 | ** attached database. It is not an error if database zDb is not attached |
9994 | ** to the database when the session object is created. |
9995 | */ |
9996 | SQLITE_API int sqlite3session_create( |
9997 | sqlite3 *db, /* Database handle */ |
9998 | const char *zDb, /* Name of db (e.g. "main") */ |
9999 | sqlite3_session **ppSession /* OUT: New session object */ |
10000 | ); |
10001 | |
10002 | /* |
10003 | ** CAPI3REF: Delete A Session Object |
10004 | ** DESTRUCTOR: sqlite3_session |
10005 | ** |
10006 | ** Delete a session object previously allocated using |
10007 | ** [sqlite3session_create()]. Once a session object has been deleted, the |
10008 | ** results of attempting to use pSession with any other session module |
10009 | ** function are undefined. |
10010 | ** |
10011 | ** Session objects must be deleted before the database handle to which they |
10012 | ** are attached is closed. Refer to the documentation for |
10013 | ** [sqlite3session_create()] for details. |
10014 | */ |
10015 | SQLITE_API void sqlite3session_delete(sqlite3_session *pSession); |
10016 | |
10017 | |
10018 | /* |
10019 | ** CAPI3REF: Enable Or Disable A Session Object |
10020 | ** METHOD: sqlite3_session |
10021 | ** |
10022 | ** Enable or disable the recording of changes by a session object. When |
10023 | ** enabled, a session object records changes made to the database. When |
10024 | ** disabled - it does not. A newly created session object is enabled. |
10025 | ** Refer to the documentation for [sqlite3session_changeset()] for further |
10026 | ** details regarding how enabling and disabling a session object affects |
10027 | ** the eventual changesets. |
10028 | ** |
10029 | ** Passing zero to this function disables the session. Passing a value |
10030 | ** greater than zero enables it. Passing a value less than zero is a |
10031 | ** no-op, and may be used to query the current state of the session. |
10032 | ** |
10033 | ** The return value indicates the final state of the session object: 0 if |
10034 | ** the session is disabled, or 1 if it is enabled. |
10035 | */ |
10036 | SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable); |
10037 | |
10038 | /* |
10039 | ** CAPI3REF: Set Or Clear the Indirect Change Flag |
10040 | ** METHOD: sqlite3_session |
10041 | ** |
10042 | ** Each change recorded by a session object is marked as either direct or |
10043 | ** indirect. A change is marked as indirect if either: |
10044 | ** |
10045 | ** <ul> |
10046 | ** <li> The session object "indirect" flag is set when the change is |
10047 | ** made, or |
10048 | ** <li> The change is made by an SQL trigger or foreign key action |
10049 | ** instead of directly as a result of a users SQL statement. |
10050 | ** </ul> |
10051 | ** |
10052 | ** If a single row is affected by more than one operation within a session, |
10053 | ** then the change is considered indirect if all operations meet the criteria |
10054 | ** for an indirect change above, or direct otherwise. |
10055 | ** |
10056 | ** This function is used to set, clear or query the session object indirect |
10057 | ** flag. If the second argument passed to this function is zero, then the |
10058 | ** indirect flag is cleared. If it is greater than zero, the indirect flag |
10059 | ** is set. Passing a value less than zero does not modify the current value |
10060 | ** of the indirect flag, and may be used to query the current state of the |
10061 | ** indirect flag for the specified session object. |
10062 | ** |
10063 | ** The return value indicates the final state of the indirect flag: 0 if |
10064 | ** it is clear, or 1 if it is set. |
10065 | */ |
10066 | SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect); |
10067 | |
10068 | /* |
10069 | ** CAPI3REF: Attach A Table To A Session Object |
10070 | ** METHOD: sqlite3_session |
10071 | ** |
10072 | ** If argument zTab is not NULL, then it is the name of a table to attach |
10073 | ** to the session object passed as the first argument. All subsequent changes |
10074 | ** made to the table while the session object is enabled will be recorded. See |
10075 | ** documentation for [sqlite3session_changeset()] for further details. |
10076 | ** |
10077 | ** Or, if argument zTab is NULL, then changes are recorded for all tables |
10078 | ** in the database. If additional tables are added to the database (by |
10079 | ** executing "CREATE TABLE" statements) after this call is made, changes for |
10080 | ** the new tables are also recorded. |
10081 | ** |
10082 | ** Changes can only be recorded for tables that have a PRIMARY KEY explicitly |
10083 | ** defined as part of their CREATE TABLE statement. It does not matter if the |
10084 | ** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY |
10085 | ** KEY may consist of a single column, or may be a composite key. |
10086 | ** |
10087 | ** It is not an error if the named table does not exist in the database. Nor |
10088 | ** is it an error if the named table does not have a PRIMARY KEY. However, |
10089 | ** no changes will be recorded in either of these scenarios. |
10090 | ** |
10091 | ** Changes are not recorded for individual rows that have NULL values stored |
10092 | ** in one or more of their PRIMARY KEY columns. |
10093 | ** |
10094 | ** SQLITE_OK is returned if the call completes without error. Or, if an error |
10095 | ** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned. |
10096 | ** |
10097 | ** <h3>Special sqlite_stat1 Handling</h3> |
10098 | ** |
10099 | ** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to |
10100 | ** some of the rules above. In SQLite, the schema of sqlite_stat1 is: |
10101 | ** <pre> |
10102 | ** CREATE TABLE sqlite_stat1(tbl,idx,stat) |
10103 | ** </pre> |
10104 | ** |
10105 | ** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are |
10106 | ** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes |
10107 | ** are recorded for rows for which (idx IS NULL) is true. However, for such |
10108 | ** rows a zero-length blob (SQL value X'') is stored in the changeset or |
10109 | ** patchset instead of a NULL value. This allows such changesets to be |
10110 | ** manipulated by legacy implementations of sqlite3changeset_invert(), |
10111 | ** concat() and similar. |
10112 | ** |
10113 | ** The sqlite3changeset_apply() function automatically converts the |
10114 | ** zero-length blob back to a NULL value when updating the sqlite_stat1 |
10115 | ** table. However, if the application calls sqlite3changeset_new(), |
10116 | ** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset |
10117 | ** iterator directly (including on a changeset iterator passed to a |
10118 | ** conflict-handler callback) then the X'' value is returned. The application |
10119 | ** must translate X'' to NULL itself if required. |
10120 | ** |
10121 | ** Legacy (older than 3.22.0) versions of the sessions module cannot capture |
10122 | ** changes made to the sqlite_stat1 table. Legacy versions of the |
10123 | ** sqlite3changeset_apply() function silently ignore any modifications to the |
10124 | ** sqlite_stat1 table that are part of a changeset or patchset. |
10125 | */ |
10126 | SQLITE_API int sqlite3session_attach( |
10127 | sqlite3_session *pSession, /* Session object */ |
10128 | const char *zTab /* Table name */ |
10129 | ); |
10130 | |
10131 | /* |
10132 | ** CAPI3REF: Set a table filter on a Session Object. |
10133 | ** METHOD: sqlite3_session |
10134 | ** |
10135 | ** The second argument (xFilter) is the "filter callback". For changes to rows |
10136 | ** in tables that are not attached to the Session object, the filter is called |
10137 | ** to determine whether changes to the table's rows should be tracked or not. |
10138 | ** If xFilter returns 0, changes are not tracked. Note that once a table is |
10139 | ** attached, xFilter will not be called again. |
10140 | */ |
10141 | SQLITE_API void sqlite3session_table_filter( |
10142 | sqlite3_session *pSession, /* Session object */ |
10143 | int(*xFilter)( |
10144 | void *pCtx, /* Copy of third arg to _filter_table() */ |
10145 | const char *zTab /* Table name */ |
10146 | ), |
10147 | void *pCtx /* First argument passed to xFilter */ |
10148 | ); |
10149 | |
10150 | /* |
10151 | ** CAPI3REF: Generate A Changeset From A Session Object |
10152 | ** METHOD: sqlite3_session |
10153 | ** |
10154 | ** Obtain a changeset containing changes to the tables attached to the |
10155 | ** session object passed as the first argument. If successful, |
10156 | ** set *ppChangeset to point to a buffer containing the changeset |
10157 | ** and *pnChangeset to the size of the changeset in bytes before returning |
10158 | ** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to |
10159 | ** zero and return an SQLite error code. |
10160 | ** |
10161 | ** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes, |
10162 | ** each representing a change to a single row of an attached table. An INSERT |
10163 | ** change contains the values of each field of a new database row. A DELETE |
10164 | ** contains the original values of each field of a deleted database row. An |
10165 | ** UPDATE change contains the original values of each field of an updated |
10166 | ** database row along with the updated values for each updated non-primary-key |
10167 | ** column. It is not possible for an UPDATE change to represent a change that |
10168 | ** modifies the values of primary key columns. If such a change is made, it |
10169 | ** is represented in a changeset as a DELETE followed by an INSERT. |
10170 | ** |
10171 | ** Changes are not recorded for rows that have NULL values stored in one or |
10172 | ** more of their PRIMARY KEY columns. If such a row is inserted or deleted, |
10173 | ** no corresponding change is present in the changesets returned by this |
10174 | ** function. If an existing row with one or more NULL values stored in |
10175 | ** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL, |
10176 | ** only an INSERT is appears in the changeset. Similarly, if an existing row |
10177 | ** with non-NULL PRIMARY KEY values is updated so that one or more of its |
10178 | ** PRIMARY KEY columns are set to NULL, the resulting changeset contains a |
10179 | ** DELETE change only. |
10180 | ** |
10181 | ** The contents of a changeset may be traversed using an iterator created |
10182 | ** using the [sqlite3changeset_start()] API. A changeset may be applied to |
10183 | ** a database with a compatible schema using the [sqlite3changeset_apply()] |
10184 | ** API. |
10185 | ** |
10186 | ** Within a changeset generated by this function, all changes related to a |
10187 | ** single table are grouped together. In other words, when iterating through |
10188 | ** a changeset or when applying a changeset to a database, all changes related |
10189 | ** to a single table are processed before moving on to the next table. Tables |
10190 | ** are sorted in the same order in which they were attached (or auto-attached) |
10191 | ** to the sqlite3_session object. The order in which the changes related to |
10192 | ** a single table are stored is undefined. |
10193 | ** |
10194 | ** Following a successful call to this function, it is the responsibility of |
10195 | ** the caller to eventually free the buffer that *ppChangeset points to using |
10196 | ** [sqlite3_free()]. |
10197 | ** |
10198 | ** <h3>Changeset Generation</h3> |
10199 | ** |
10200 | ** Once a table has been attached to a session object, the session object |
10201 | ** records the primary key values of all new rows inserted into the table. |
10202 | ** It also records the original primary key and other column values of any |
10203 | ** deleted or updated rows. For each unique primary key value, data is only |
10204 | ** recorded once - the first time a row with said primary key is inserted, |
10205 | ** updated or deleted in the lifetime of the session. |
10206 | ** |
10207 | ** There is one exception to the previous paragraph: when a row is inserted, |
10208 | ** updated or deleted, if one or more of its primary key columns contain a |
10209 | ** NULL value, no record of the change is made. |
10210 | ** |
10211 | ** The session object therefore accumulates two types of records - those |
10212 | ** that consist of primary key values only (created when the user inserts |
10213 | ** a new record) and those that consist of the primary key values and the |
10214 | ** original values of other table columns (created when the users deletes |
10215 | ** or updates a record). |
10216 | ** |
10217 | ** When this function is called, the requested changeset is created using |
10218 | ** both the accumulated records and the current contents of the database |
10219 | ** file. Specifically: |
10220 | ** |
10221 | ** <ul> |
10222 | ** <li> For each record generated by an insert, the database is queried |
10223 | ** for a row with a matching primary key. If one is found, an INSERT |
10224 | ** change is added to the changeset. If no such row is found, no change |
10225 | ** is added to the changeset. |
10226 | ** |
10227 | ** <li> For each record generated by an update or delete, the database is |
10228 | ** queried for a row with a matching primary key. If such a row is |
10229 | ** found and one or more of the non-primary key fields have been |
10230 | ** modified from their original values, an UPDATE change is added to |
10231 | ** the changeset. Or, if no such row is found in the table, a DELETE |
10232 | ** change is added to the changeset. If there is a row with a matching |
10233 | ** primary key in the database, but all fields contain their original |
10234 | ** values, no change is added to the changeset. |
10235 | ** </ul> |
10236 | ** |
10237 | ** This means, amongst other things, that if a row is inserted and then later |
10238 | ** deleted while a session object is active, neither the insert nor the delete |
10239 | ** will be present in the changeset. Or if a row is deleted and then later a |
10240 | ** row with the same primary key values inserted while a session object is |
10241 | ** active, the resulting changeset will contain an UPDATE change instead of |
10242 | ** a DELETE and an INSERT. |
10243 | ** |
10244 | ** When a session object is disabled (see the [sqlite3session_enable()] API), |
10245 | ** it does not accumulate records when rows are inserted, updated or deleted. |
10246 | ** This may appear to have some counter-intuitive effects if a single row |
10247 | ** is written to more than once during a session. For example, if a row |
10248 | ** is inserted while a session object is enabled, then later deleted while |
10249 | ** the same session object is disabled, no INSERT record will appear in the |
10250 | ** changeset, even though the delete took place while the session was disabled. |
10251 | ** Or, if one field of a row is updated while a session is disabled, and |
10252 | ** another field of the same row is updated while the session is enabled, the |
10253 | ** resulting changeset will contain an UPDATE change that updates both fields. |
10254 | */ |
10255 | SQLITE_API int sqlite3session_changeset( |
10256 | sqlite3_session *pSession, /* Session object */ |
10257 | int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */ |
10258 | void **ppChangeset /* OUT: Buffer containing changeset */ |
10259 | ); |
10260 | |
10261 | /* |
10262 | ** CAPI3REF: Load The Difference Between Tables Into A Session |
10263 | ** METHOD: sqlite3_session |
10264 | ** |
10265 | ** If it is not already attached to the session object passed as the first |
10266 | ** argument, this function attaches table zTbl in the same manner as the |
10267 | ** [sqlite3session_attach()] function. If zTbl does not exist, or if it |
10268 | ** does not have a primary key, this function is a no-op (but does not return |
10269 | ** an error). |
10270 | ** |
10271 | ** Argument zFromDb must be the name of a database ("main", "temp" etc.) |
10272 | ** attached to the same database handle as the session object that contains |
10273 | ** a table compatible with the table attached to the session by this function. |
10274 | ** A table is considered compatible if it: |
10275 | ** |
10276 | ** <ul> |
10277 | ** <li> Has the same name, |
10278 | ** <li> Has the same set of columns declared in the same order, and |
10279 | ** <li> Has the same PRIMARY KEY definition. |
10280 | ** </ul> |
10281 | ** |
10282 | ** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables |
10283 | ** are compatible but do not have any PRIMARY KEY columns, it is not an error |
10284 | ** but no changes are added to the session object. As with other session |
10285 | ** APIs, tables without PRIMARY KEYs are simply ignored. |
10286 | ** |
10287 | ** This function adds a set of changes to the session object that could be |
10288 | ** used to update the table in database zFrom (call this the "from-table") |
10289 | ** so that its content is the same as the table attached to the session |
10290 | ** object (call this the "to-table"). Specifically: |
10291 | ** |
10292 | ** <ul> |
10293 | ** <li> For each row (primary key) that exists in the to-table but not in |
10294 | ** the from-table, an INSERT record is added to the session object. |
10295 | ** |
10296 | ** <li> For each row (primary key) that exists in the to-table but not in |
10297 | ** the from-table, a DELETE record is added to the session object. |
10298 | ** |
10299 | ** <li> For each row (primary key) that exists in both tables, but features |
10300 | ** different non-PK values in each, an UPDATE record is added to the |
10301 | ** session. |
10302 | ** </ul> |
10303 | ** |
10304 | ** To clarify, if this function is called and then a changeset constructed |
10305 | ** using [sqlite3session_changeset()], then after applying that changeset to |
10306 | ** database zFrom the contents of the two compatible tables would be |
10307 | ** identical. |
10308 | ** |
10309 | ** It an error if database zFrom does not exist or does not contain the |
10310 | ** required compatible table. |
10311 | ** |
10312 | ** If the operation is successful, SQLITE_OK is returned. Otherwise, an SQLite |
10313 | ** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg |
10314 | ** may be set to point to a buffer containing an English language error |
10315 | ** message. It is the responsibility of the caller to free this buffer using |
10316 | ** sqlite3_free(). |
10317 | */ |
10318 | SQLITE_API int sqlite3session_diff( |
10319 | sqlite3_session *pSession, |
10320 | const char *zFromDb, |
10321 | const char *zTbl, |
10322 | char **pzErrMsg |
10323 | ); |
10324 | |
10325 | |
10326 | /* |
10327 | ** CAPI3REF: Generate A Patchset From A Session Object |
10328 | ** METHOD: sqlite3_session |
10329 | ** |
10330 | ** The differences between a patchset and a changeset are that: |
10331 | ** |
10332 | ** <ul> |
10333 | ** <li> DELETE records consist of the primary key fields only. The |
10334 | ** original values of other fields are omitted. |
10335 | ** <li> The original values of any modified fields are omitted from |
10336 | ** UPDATE records. |
10337 | ** </ul> |
10338 | ** |
10339 | ** A patchset blob may be used with up to date versions of all |
10340 | ** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(), |
10341 | ** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly, |
10342 | ** attempting to use a patchset blob with old versions of the |
10343 | ** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error. |
10344 | ** |
10345 | ** Because the non-primary key "old.*" fields are omitted, no |
10346 | ** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset |
10347 | ** is passed to the sqlite3changeset_apply() API. Other conflict types work |
10348 | ** in the same way as for changesets. |
10349 | ** |
10350 | ** Changes within a patchset are ordered in the same way as for changesets |
10351 | ** generated by the sqlite3session_changeset() function (i.e. all changes for |
10352 | ** a single table are grouped together, tables appear in the order in which |
10353 | ** they were attached to the session object). |
10354 | */ |
10355 | SQLITE_API int sqlite3session_patchset( |
10356 | sqlite3_session *pSession, /* Session object */ |
10357 | int *pnPatchset, /* OUT: Size of buffer at *ppPatchset */ |
10358 | void **ppPatchset /* OUT: Buffer containing patchset */ |
10359 | ); |
10360 | |
10361 | /* |
10362 | ** CAPI3REF: Test if a changeset has recorded any changes. |
10363 | ** |
10364 | ** Return non-zero if no changes to attached tables have been recorded by |
10365 | ** the session object passed as the first argument. Otherwise, if one or |
10366 | ** more changes have been recorded, return zero. |
10367 | ** |
10368 | ** Even if this function returns zero, it is possible that calling |
10369 | ** [sqlite3session_changeset()] on the session handle may still return a |
10370 | ** changeset that contains no changes. This can happen when a row in |
10371 | ** an attached table is modified and then later on the original values |
10372 | ** are restored. However, if this function returns non-zero, then it is |
10373 | ** guaranteed that a call to sqlite3session_changeset() will return a |
10374 | ** changeset containing zero changes. |
10375 | */ |
10376 | SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession); |
10377 | |
10378 | /* |
10379 | ** CAPI3REF: Create An Iterator To Traverse A Changeset |
10380 | ** CONSTRUCTOR: sqlite3_changeset_iter |
10381 | ** |
10382 | ** Create an iterator used to iterate through the contents of a changeset. |
10383 | ** If successful, *pp is set to point to the iterator handle and SQLITE_OK |
10384 | ** is returned. Otherwise, if an error occurs, *pp is set to zero and an |
10385 | ** SQLite error code is returned. |
10386 | ** |
10387 | ** The following functions can be used to advance and query a changeset |
10388 | ** iterator created by this function: |
10389 | ** |
10390 | ** <ul> |
10391 | ** <li> [sqlite3changeset_next()] |
10392 | ** <li> [sqlite3changeset_op()] |
10393 | ** <li> [sqlite3changeset_new()] |
10394 | ** <li> [sqlite3changeset_old()] |
10395 | ** </ul> |
10396 | ** |
10397 | ** It is the responsibility of the caller to eventually destroy the iterator |
10398 | ** by passing it to [sqlite3changeset_finalize()]. The buffer containing the |
10399 | ** changeset (pChangeset) must remain valid until after the iterator is |
10400 | ** destroyed. |
10401 | ** |
10402 | ** Assuming the changeset blob was created by one of the |
10403 | ** [sqlite3session_changeset()], [sqlite3changeset_concat()] or |
10404 | ** [sqlite3changeset_invert()] functions, all changes within the changeset |
10405 | ** that apply to a single table are grouped together. This means that when |
10406 | ** an application iterates through a changeset using an iterator created by |
10407 | ** this function, all changes that relate to a single table are visited |
10408 | ** consecutively. There is no chance that the iterator will visit a change |
10409 | ** the applies to table X, then one for table Y, and then later on visit |
10410 | ** another change for table X. |
10411 | ** |
10412 | ** The behavior of sqlite3changeset_start_v2() and its streaming equivalent |
10413 | ** may be modified by passing a combination of |
10414 | ** [SQLITE_CHANGESETSTART_INVERT | supported flags] as the 4th parameter. |
10415 | ** |
10416 | ** Note that the sqlite3changeset_start_v2() API is still <b>experimental</b> |
10417 | ** and therefore subject to change. |
10418 | */ |
10419 | SQLITE_API int sqlite3changeset_start( |
10420 | sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ |
10421 | int nChangeset, /* Size of changeset blob in bytes */ |
10422 | void *pChangeset /* Pointer to blob containing changeset */ |
10423 | ); |
10424 | SQLITE_API int sqlite3changeset_start_v2( |
10425 | sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ |
10426 | int nChangeset, /* Size of changeset blob in bytes */ |
10427 | void *pChangeset, /* Pointer to blob containing changeset */ |
10428 | int flags /* SESSION_CHANGESETSTART_* flags */ |
10429 | ); |
10430 | |
10431 | /* |
10432 | ** CAPI3REF: Flags for sqlite3changeset_start_v2 |
10433 | ** |
10434 | ** The following flags may passed via the 4th parameter to |
10435 | ** [sqlite3changeset_start_v2] and [sqlite3changeset_start_v2_strm]: |
10436 | ** |
10437 | ** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd> |
10438 | ** Invert the changeset while iterating through it. This is equivalent to |
10439 | ** inverting a changeset using sqlite3changeset_invert() before applying it. |
10440 | ** It is an error to specify this flag with a patchset. |
10441 | */ |
10442 | #define SQLITE_CHANGESETSTART_INVERT 0x0002 |
10443 | |
10444 | |
10445 | /* |
10446 | ** CAPI3REF: Advance A Changeset Iterator |
10447 | ** METHOD: sqlite3_changeset_iter |
10448 | ** |
10449 | ** This function may only be used with iterators created by the function |
10450 | ** [sqlite3changeset_start()]. If it is called on an iterator passed to |
10451 | ** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE |
10452 | ** is returned and the call has no effect. |
10453 | ** |
10454 | ** Immediately after an iterator is created by sqlite3changeset_start(), it |
10455 | ** does not point to any change in the changeset. Assuming the changeset |
10456 | ** is not empty, the first call to this function advances the iterator to |
10457 | ** point to the first change in the changeset. Each subsequent call advances |
10458 | ** the iterator to point to the next change in the changeset (if any). If |
10459 | ** no error occurs and the iterator points to a valid change after a call |
10460 | ** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned. |
10461 | ** Otherwise, if all changes in the changeset have already been visited, |
10462 | ** SQLITE_DONE is returned. |
10463 | ** |
10464 | ** If an error occurs, an SQLite error code is returned. Possible error |
10465 | ** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or |
10466 | ** SQLITE_NOMEM. |
10467 | */ |
10468 | SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter); |
10469 | |
10470 | /* |
10471 | ** CAPI3REF: Obtain The Current Operation From A Changeset Iterator |
10472 | ** METHOD: sqlite3_changeset_iter |
10473 | ** |
10474 | ** The pIter argument passed to this function may either be an iterator |
10475 | ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator |
10476 | ** created by [sqlite3changeset_start()]. In the latter case, the most recent |
10477 | ** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this |
10478 | ** is not the case, this function returns [SQLITE_MISUSE]. |
10479 | ** |
10480 | ** If argument pzTab is not NULL, then *pzTab is set to point to a |
10481 | ** nul-terminated utf-8 encoded string containing the name of the table |
10482 | ** affected by the current change. The buffer remains valid until either |
10483 | ** sqlite3changeset_next() is called on the iterator or until the |
10484 | ** conflict-handler function returns. If pnCol is not NULL, then *pnCol is |
10485 | ** set to the number of columns in the table affected by the change. If |
10486 | ** pbIndirect is not NULL, then *pbIndirect is set to true (1) if the change |
10487 | ** is an indirect change, or false (0) otherwise. See the documentation for |
10488 | ** [sqlite3session_indirect()] for a description of direct and indirect |
10489 | ** changes. Finally, if pOp is not NULL, then *pOp is set to one of |
10490 | ** [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], depending on the |
10491 | ** type of change that the iterator currently points to. |
10492 | ** |
10493 | ** If no error occurs, SQLITE_OK is returned. If an error does occur, an |
10494 | ** SQLite error code is returned. The values of the output variables may not |
10495 | ** be trusted in this case. |
10496 | */ |
10497 | SQLITE_API int sqlite3changeset_op( |
10498 | sqlite3_changeset_iter *pIter, /* Iterator object */ |
10499 | const char **pzTab, /* OUT: Pointer to table name */ |
10500 | int *pnCol, /* OUT: Number of columns in table */ |
10501 | int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */ |
10502 | int *pbIndirect /* OUT: True for an 'indirect' change */ |
10503 | ); |
10504 | |
10505 | /* |
10506 | ** CAPI3REF: Obtain The Primary Key Definition Of A Table |
10507 | ** METHOD: sqlite3_changeset_iter |
10508 | ** |
10509 | ** For each modified table, a changeset includes the following: |
10510 | ** |
10511 | ** <ul> |
10512 | ** <li> The number of columns in the table, and |
10513 | ** <li> Which of those columns make up the tables PRIMARY KEY. |
10514 | ** </ul> |
10515 | ** |
10516 | ** This function is used to find which columns comprise the PRIMARY KEY of |
10517 | ** the table modified by the change that iterator pIter currently points to. |
10518 | ** If successful, *pabPK is set to point to an array of nCol entries, where |
10519 | ** nCol is the number of columns in the table. Elements of *pabPK are set to |
10520 | ** 0x01 if the corresponding column is part of the tables primary key, or |
10521 | ** 0x00 if it is not. |
10522 | ** |
10523 | ** If argument pnCol is not NULL, then *pnCol is set to the number of columns |
10524 | ** in the table. |
10525 | ** |
10526 | ** If this function is called when the iterator does not point to a valid |
10527 | ** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise, |
10528 | ** SQLITE_OK is returned and the output variables populated as described |
10529 | ** above. |
10530 | */ |
10531 | SQLITE_API int sqlite3changeset_pk( |
10532 | sqlite3_changeset_iter *pIter, /* Iterator object */ |
10533 | unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */ |
10534 | int *pnCol /* OUT: Number of entries in output array */ |
10535 | ); |
10536 | |
10537 | /* |
10538 | ** CAPI3REF: Obtain old.* Values From A Changeset Iterator |
10539 | ** METHOD: sqlite3_changeset_iter |
10540 | ** |
10541 | ** The pIter argument passed to this function may either be an iterator |
10542 | ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator |
10543 | ** created by [sqlite3changeset_start()]. In the latter case, the most recent |
10544 | ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. |
10545 | ** Furthermore, it may only be called if the type of change that the iterator |
10546 | ** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise, |
10547 | ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. |
10548 | ** |
10549 | ** Argument iVal must be greater than or equal to 0, and less than the number |
10550 | ** of columns in the table affected by the current change. Otherwise, |
10551 | ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. |
10552 | ** |
10553 | ** If successful, this function sets *ppValue to point to a protected |
10554 | ** sqlite3_value object containing the iVal'th value from the vector of |
10555 | ** original row values stored as part of the UPDATE or DELETE change and |
10556 | ** returns SQLITE_OK. The name of the function comes from the fact that this |
10557 | ** is similar to the "old.*" columns available to update or delete triggers. |
10558 | ** |
10559 | ** If some other error occurs (e.g. an OOM condition), an SQLite error code |
10560 | ** is returned and *ppValue is set to NULL. |
10561 | */ |
10562 | SQLITE_API int sqlite3changeset_old( |
10563 | sqlite3_changeset_iter *pIter, /* Changeset iterator */ |
10564 | int iVal, /* Column number */ |
10565 | sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */ |
10566 | ); |
10567 | |
10568 | /* |
10569 | ** CAPI3REF: Obtain new.* Values From A Changeset Iterator |
10570 | ** METHOD: sqlite3_changeset_iter |
10571 | ** |
10572 | ** The pIter argument passed to this function may either be an iterator |
10573 | ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator |
10574 | ** created by [sqlite3changeset_start()]. In the latter case, the most recent |
10575 | ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. |
10576 | ** Furthermore, it may only be called if the type of change that the iterator |
10577 | ** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise, |
10578 | ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. |
10579 | ** |
10580 | ** Argument iVal must be greater than or equal to 0, and less than the number |
10581 | ** of columns in the table affected by the current change. Otherwise, |
10582 | ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. |
10583 | ** |
10584 | ** If successful, this function sets *ppValue to point to a protected |
10585 | ** sqlite3_value object containing the iVal'th value from the vector of |
10586 | ** new row values stored as part of the UPDATE or INSERT change and |
10587 | ** returns SQLITE_OK. If the change is an UPDATE and does not include |
10588 | ** a new value for the requested column, *ppValue is set to NULL and |
10589 | ** SQLITE_OK returned. The name of the function comes from the fact that |
10590 | ** this is similar to the "new.*" columns available to update or delete |
10591 | ** triggers. |
10592 | ** |
10593 | ** If some other error occurs (e.g. an OOM condition), an SQLite error code |
10594 | ** is returned and *ppValue is set to NULL. |
10595 | */ |
10596 | SQLITE_API int sqlite3changeset_new( |
10597 | sqlite3_changeset_iter *pIter, /* Changeset iterator */ |
10598 | int iVal, /* Column number */ |
10599 | sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */ |
10600 | ); |
10601 | |
10602 | /* |
10603 | ** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator |
10604 | ** METHOD: sqlite3_changeset_iter |
10605 | ** |
10606 | ** This function should only be used with iterator objects passed to a |
10607 | ** conflict-handler callback by [sqlite3changeset_apply()] with either |
10608 | ** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function |
10609 | ** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue |
10610 | ** is set to NULL. |
10611 | ** |
10612 | ** Argument iVal must be greater than or equal to 0, and less than the number |
10613 | ** of columns in the table affected by the current change. Otherwise, |
10614 | ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. |
10615 | ** |
10616 | ** If successful, this function sets *ppValue to point to a protected |
10617 | ** sqlite3_value object containing the iVal'th value from the |
10618 | ** "conflicting row" associated with the current conflict-handler callback |
10619 | ** and returns SQLITE_OK. |
10620 | ** |
10621 | ** If some other error occurs (e.g. an OOM condition), an SQLite error code |
10622 | ** is returned and *ppValue is set to NULL. |
10623 | */ |
10624 | SQLITE_API int sqlite3changeset_conflict( |
10625 | sqlite3_changeset_iter *pIter, /* Changeset iterator */ |
10626 | int iVal, /* Column number */ |
10627 | sqlite3_value **ppValue /* OUT: Value from conflicting row */ |
10628 | ); |
10629 | |
10630 | /* |
10631 | ** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations |
10632 | ** METHOD: sqlite3_changeset_iter |
10633 | ** |
10634 | ** This function may only be called with an iterator passed to an |
10635 | ** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case |
10636 | ** it sets the output variable to the total number of known foreign key |
10637 | ** violations in the destination database and returns SQLITE_OK. |
10638 | ** |
10639 | ** In all other cases this function returns SQLITE_MISUSE. |
10640 | */ |
10641 | SQLITE_API int sqlite3changeset_fk_conflicts( |
10642 | sqlite3_changeset_iter *pIter, /* Changeset iterator */ |
10643 | int *pnOut /* OUT: Number of FK violations */ |
10644 | ); |
10645 | |
10646 | |
10647 | /* |
10648 | ** CAPI3REF: Finalize A Changeset Iterator |
10649 | ** METHOD: sqlite3_changeset_iter |
10650 | ** |
10651 | ** This function is used to finalize an iterator allocated with |
10652 | ** [sqlite3changeset_start()]. |
10653 | ** |
10654 | ** This function should only be called on iterators created using the |
10655 | ** [sqlite3changeset_start()] function. If an application calls this |
10656 | ** function with an iterator passed to a conflict-handler by |
10657 | ** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the |
10658 | ** call has no effect. |
10659 | ** |
10660 | ** If an error was encountered within a call to an sqlite3changeset_xxx() |
10661 | ** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an |
10662 | ** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding |
10663 | ** to that error is returned by this function. Otherwise, SQLITE_OK is |
10664 | ** returned. This is to allow the following pattern (pseudo-code): |
10665 | ** |
10666 | ** <pre> |
10667 | ** sqlite3changeset_start(); |
10668 | ** while( SQLITE_ROW==sqlite3changeset_next() ){ |
10669 | ** // Do something with change. |
10670 | ** } |
10671 | ** rc = sqlite3changeset_finalize(); |
10672 | ** if( rc!=SQLITE_OK ){ |
10673 | ** // An error has occurred |
10674 | ** } |
10675 | ** </pre> |
10676 | */ |
10677 | SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter); |
10678 | |
10679 | /* |
10680 | ** CAPI3REF: Invert A Changeset |
10681 | ** |
10682 | ** This function is used to "invert" a changeset object. Applying an inverted |
10683 | ** changeset to a database reverses the effects of applying the uninverted |
10684 | ** changeset. Specifically: |
10685 | ** |
10686 | ** <ul> |
10687 | ** <li> Each DELETE change is changed to an INSERT, and |
10688 | ** <li> Each INSERT change is changed to a DELETE, and |
10689 | ** <li> For each UPDATE change, the old.* and new.* values are exchanged. |
10690 | ** </ul> |
10691 | ** |
10692 | ** This function does not change the order in which changes appear within |
10693 | ** the changeset. It merely reverses the sense of each individual change. |
10694 | ** |
10695 | ** If successful, a pointer to a buffer containing the inverted changeset |
10696 | ** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and |
10697 | ** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are |
10698 | ** zeroed and an SQLite error code returned. |
10699 | ** |
10700 | ** It is the responsibility of the caller to eventually call sqlite3_free() |
10701 | ** on the *ppOut pointer to free the buffer allocation following a successful |
10702 | ** call to this function. |
10703 | ** |
10704 | ** WARNING/TODO: This function currently assumes that the input is a valid |
10705 | ** changeset. If it is not, the results are undefined. |
10706 | */ |
10707 | SQLITE_API int sqlite3changeset_invert( |
10708 | int nIn, const void *pIn, /* Input changeset */ |
10709 | int *pnOut, void **ppOut /* OUT: Inverse of input */ |
10710 | ); |
10711 | |
10712 | /* |
10713 | ** CAPI3REF: Concatenate Two Changeset Objects |
10714 | ** |
10715 | ** This function is used to concatenate two changesets, A and B, into a |
10716 | ** single changeset. The result is a changeset equivalent to applying |
10717 | ** changeset A followed by changeset B. |
10718 | ** |
10719 | ** This function combines the two input changesets using an |
10720 | ** sqlite3_changegroup object. Calling it produces similar results as the |
10721 | ** following code fragment: |
10722 | ** |
10723 | ** <pre> |
10724 | ** sqlite3_changegroup *pGrp; |
10725 | ** rc = sqlite3_changegroup_new(&pGrp); |
10726 | ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA); |
10727 | ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB); |
10728 | ** if( rc==SQLITE_OK ){ |
10729 | ** rc = sqlite3changegroup_output(pGrp, pnOut, ppOut); |
10730 | ** }else{ |
10731 | ** *ppOut = 0; |
10732 | ** *pnOut = 0; |
10733 | ** } |
10734 | ** </pre> |
10735 | ** |
10736 | ** Refer to the sqlite3_changegroup documentation below for details. |
10737 | */ |
10738 | SQLITE_API int sqlite3changeset_concat( |
10739 | int nA, /* Number of bytes in buffer pA */ |
10740 | void *pA, /* Pointer to buffer containing changeset A */ |
10741 | int nB, /* Number of bytes in buffer pB */ |
10742 | void *pB, /* Pointer to buffer containing changeset B */ |
10743 | int *pnOut, /* OUT: Number of bytes in output changeset */ |
10744 | void **ppOut /* OUT: Buffer containing output changeset */ |
10745 | ); |
10746 | |
10747 | |
10748 | /* |
10749 | ** CAPI3REF: Changegroup Handle |
10750 | ** |
10751 | ** A changegroup is an object used to combine two or more |
10752 | ** [changesets] or [patchsets] |
10753 | */ |
10754 | typedef struct sqlite3_changegroup sqlite3_changegroup; |
10755 | |
10756 | /* |
10757 | ** CAPI3REF: Create A New Changegroup Object |
10758 | ** CONSTRUCTOR: sqlite3_changegroup |
10759 | ** |
10760 | ** An sqlite3_changegroup object is used to combine two or more changesets |
10761 | ** (or patchsets) into a single changeset (or patchset). A single changegroup |
10762 | ** object may combine changesets or patchsets, but not both. The output is |
10763 | ** always in the same format as the input. |
10764 | ** |
10765 | ** If successful, this function returns SQLITE_OK and populates (*pp) with |
10766 | ** a pointer to a new sqlite3_changegroup object before returning. The caller |
10767 | ** should eventually free the returned object using a call to |
10768 | ** sqlite3changegroup_delete(). If an error occurs, an SQLite error code |
10769 | ** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL. |
10770 | ** |
10771 | ** The usual usage pattern for an sqlite3_changegroup object is as follows: |
10772 | ** |
10773 | ** <ul> |
10774 | ** <li> It is created using a call to sqlite3changegroup_new(). |
10775 | ** |
10776 | ** <li> Zero or more changesets (or patchsets) are added to the object |
10777 | ** by calling sqlite3changegroup_add(). |
10778 | ** |
10779 | ** <li> The result of combining all input changesets together is obtained |
10780 | ** by the application via a call to sqlite3changegroup_output(). |
10781 | ** |
10782 | ** <li> The object is deleted using a call to sqlite3changegroup_delete(). |
10783 | ** </ul> |
10784 | ** |
10785 | ** Any number of calls to add() and output() may be made between the calls to |
10786 | ** new() and delete(), and in any order. |
10787 | ** |
10788 | ** As well as the regular sqlite3changegroup_add() and |
10789 | ** sqlite3changegroup_output() functions, also available are the streaming |
10790 | ** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm(). |
10791 | */ |
10792 | SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp); |
10793 | |
10794 | /* |
10795 | ** CAPI3REF: Add A Changeset To A Changegroup |
10796 | ** METHOD: sqlite3_changegroup |
10797 | ** |
10798 | ** Add all changes within the changeset (or patchset) in buffer pData (size |
10799 | ** nData bytes) to the changegroup. |
10800 | ** |
10801 | ** If the buffer contains a patchset, then all prior calls to this function |
10802 | ** on the same changegroup object must also have specified patchsets. Or, if |
10803 | ** the buffer contains a changeset, so must have the earlier calls to this |
10804 | ** function. Otherwise, SQLITE_ERROR is returned and no changes are added |
10805 | ** to the changegroup. |
10806 | ** |
10807 | ** Rows within the changeset and changegroup are identified by the values in |
10808 | ** their PRIMARY KEY columns. A change in the changeset is considered to |
10809 | ** apply to the same row as a change already present in the changegroup if |
10810 | ** the two rows have the same primary key. |
10811 | ** |
10812 | ** Changes to rows that do not already appear in the changegroup are |
10813 | ** simply copied into it. Or, if both the new changeset and the changegroup |
10814 | ** contain changes that apply to a single row, the final contents of the |
10815 | ** changegroup depends on the type of each change, as follows: |
10816 | ** |
10817 | ** <table border=1 style="margin-left:8ex;margin-right:8ex"> |
10818 | ** <tr><th style="white-space:pre">Existing Change </th> |
10819 | ** <th style="white-space:pre">New Change </th> |
10820 | ** <th>Output Change |
10821 | ** <tr><td>INSERT <td>INSERT <td> |
10822 | ** The new change is ignored. This case does not occur if the new |
10823 | ** changeset was recorded immediately after the changesets already |
10824 | ** added to the changegroup. |
10825 | ** <tr><td>INSERT <td>UPDATE <td> |
10826 | ** The INSERT change remains in the changegroup. The values in the |
10827 | ** INSERT change are modified as if the row was inserted by the |
10828 | ** existing change and then updated according to the new change. |
10829 | ** <tr><td>INSERT <td>DELETE <td> |
10830 | ** The existing INSERT is removed from the changegroup. The DELETE is |
10831 | ** not added. |
10832 | ** <tr><td>UPDATE <td>INSERT <td> |
10833 | ** The new change is ignored. This case does not occur if the new |
10834 | ** changeset was recorded immediately after the changesets already |
10835 | ** added to the changegroup. |
10836 | ** <tr><td>UPDATE <td>UPDATE <td> |
10837 | ** The existing UPDATE remains within the changegroup. It is amended |
10838 | ** so that the accompanying values are as if the row was updated once |
10839 | ** by the existing change and then again by the new change. |
10840 | ** <tr><td>UPDATE <td>DELETE <td> |
10841 | ** The existing UPDATE is replaced by the new DELETE within the |
10842 | ** changegroup. |
10843 | ** <tr><td>DELETE <td>INSERT <td> |
10844 | ** If one or more of the column values in the row inserted by the |
10845 | ** new change differ from those in the row deleted by the existing |
10846 | ** change, the existing DELETE is replaced by an UPDATE within the |
10847 | ** changegroup. Otherwise, if the inserted row is exactly the same |
10848 | ** as the deleted row, the existing DELETE is simply discarded. |
10849 | ** <tr><td>DELETE <td>UPDATE <td> |
10850 | ** The new change is ignored. This case does not occur if the new |
10851 | ** changeset was recorded immediately after the changesets already |
10852 | ** added to the changegroup. |
10853 | ** <tr><td>DELETE <td>DELETE <td> |
10854 | ** The new change is ignored. This case does not occur if the new |
10855 | ** changeset was recorded immediately after the changesets already |
10856 | ** added to the changegroup. |
10857 | ** </table> |
10858 | ** |
10859 | ** If the new changeset contains changes to a table that is already present |
10860 | ** in the changegroup, then the number of columns and the position of the |
10861 | ** primary key columns for the table must be consistent. If this is not the |
10862 | ** case, this function fails with SQLITE_SCHEMA. If the input changeset |
10863 | ** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is |
10864 | ** returned. Or, if an out-of-memory condition occurs during processing, this |
10865 | ** function returns SQLITE_NOMEM. In all cases, if an error occurs the state |
10866 | ** of the final contents of the changegroup is undefined. |
10867 | ** |
10868 | ** If no error occurs, SQLITE_OK is returned. |
10869 | */ |
10870 | SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData); |
10871 | |
10872 | /* |
10873 | ** CAPI3REF: Obtain A Composite Changeset From A Changegroup |
10874 | ** METHOD: sqlite3_changegroup |
10875 | ** |
10876 | ** Obtain a buffer containing a changeset (or patchset) representing the |
10877 | ** current contents of the changegroup. If the inputs to the changegroup |
10878 | ** were themselves changesets, the output is a changeset. Or, if the |
10879 | ** inputs were patchsets, the output is also a patchset. |
10880 | ** |
10881 | ** As with the output of the sqlite3session_changeset() and |
10882 | ** sqlite3session_patchset() functions, all changes related to a single |
10883 | ** table are grouped together in the output of this function. Tables appear |
10884 | ** in the same order as for the very first changeset added to the changegroup. |
10885 | ** If the second or subsequent changesets added to the changegroup contain |
10886 | ** changes for tables that do not appear in the first changeset, they are |
10887 | ** appended onto the end of the output changeset, again in the order in |
10888 | ** which they are first encountered. |
10889 | ** |
10890 | ** If an error occurs, an SQLite error code is returned and the output |
10891 | ** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK |
10892 | ** is returned and the output variables are set to the size of and a |
10893 | ** pointer to the output buffer, respectively. In this case it is the |
10894 | ** responsibility of the caller to eventually free the buffer using a |
10895 | ** call to sqlite3_free(). |
10896 | */ |
10897 | SQLITE_API int sqlite3changegroup_output( |
10898 | sqlite3_changegroup*, |
10899 | int *pnData, /* OUT: Size of output buffer in bytes */ |
10900 | void **ppData /* OUT: Pointer to output buffer */ |
10901 | ); |
10902 | |
10903 | /* |
10904 | ** CAPI3REF: Delete A Changegroup Object |
10905 | ** DESTRUCTOR: sqlite3_changegroup |
10906 | */ |
10907 | SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*); |
10908 | |
10909 | /* |
10910 | ** CAPI3REF: Apply A Changeset To A Database |
10911 | ** |
10912 | ** Apply a changeset or patchset to a database. These functions attempt to |
10913 | ** update the "main" database attached to handle db with the changes found in |
10914 | ** the changeset passed via the second and third arguments. |
10915 | ** |
10916 | ** The fourth argument (xFilter) passed to these functions is the "filter |
10917 | ** callback". If it is not NULL, then for each table affected by at least one |
10918 | ** change in the changeset, the filter callback is invoked with |
10919 | ** the table name as the second argument, and a copy of the context pointer |
10920 | ** passed as the sixth argument as the first. If the "filter callback" |
10921 | ** returns zero, then no attempt is made to apply any changes to the table. |
10922 | ** Otherwise, if the return value is non-zero or the xFilter argument to |
10923 | ** is NULL, all changes related to the table are attempted. |
10924 | ** |
10925 | ** For each table that is not excluded by the filter callback, this function |
10926 | ** tests that the target database contains a compatible table. A table is |
10927 | ** considered compatible if all of the following are true: |
10928 | ** |
10929 | ** <ul> |
10930 | ** <li> The table has the same name as the name recorded in the |
10931 | ** changeset, and |
10932 | ** <li> The table has at least as many columns as recorded in the |
10933 | ** changeset, and |
10934 | ** <li> The table has primary key columns in the same position as |
10935 | ** recorded in the changeset. |
10936 | ** </ul> |
10937 | ** |
10938 | ** If there is no compatible table, it is not an error, but none of the |
10939 | ** changes associated with the table are applied. A warning message is issued |
10940 | ** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most |
10941 | ** one such warning is issued for each table in the changeset. |
10942 | ** |
10943 | ** For each change for which there is a compatible table, an attempt is made |
10944 | ** to modify the table contents according to the UPDATE, INSERT or DELETE |
10945 | ** change. If a change cannot be applied cleanly, the conflict handler |
10946 | ** function passed as the fifth argument to sqlite3changeset_apply() may be |
10947 | ** invoked. A description of exactly when the conflict handler is invoked for |
10948 | ** each type of change is below. |
10949 | ** |
10950 | ** Unlike the xFilter argument, xConflict may not be passed NULL. The results |
10951 | ** of passing anything other than a valid function pointer as the xConflict |
10952 | ** argument are undefined. |
10953 | ** |
10954 | ** Each time the conflict handler function is invoked, it must return one |
10955 | ** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or |
10956 | ** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned |
10957 | ** if the second argument passed to the conflict handler is either |
10958 | ** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler |
10959 | ** returns an illegal value, any changes already made are rolled back and |
10960 | ** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different |
10961 | ** actions are taken by sqlite3changeset_apply() depending on the value |
10962 | ** returned by each invocation of the conflict-handler function. Refer to |
10963 | ** the documentation for the three |
10964 | ** [SQLITE_CHANGESET_OMIT|available return values] for details. |
10965 | ** |
10966 | ** <dl> |
10967 | ** <dt>DELETE Changes<dd> |
10968 | ** For each DELETE change, the function checks if the target database |
10969 | ** contains a row with the same primary key value (or values) as the |
10970 | ** original row values stored in the changeset. If it does, and the values |
10971 | ** stored in all non-primary key columns also match the values stored in |
10972 | ** the changeset the row is deleted from the target database. |
10973 | ** |
10974 | ** If a row with matching primary key values is found, but one or more of |
10975 | ** the non-primary key fields contains a value different from the original |
10976 | ** row value stored in the changeset, the conflict-handler function is |
10977 | ** invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the |
10978 | ** database table has more columns than are recorded in the changeset, |
10979 | ** only the values of those non-primary key fields are compared against |
10980 | ** the current database contents - any trailing database table columns |
10981 | ** are ignored. |
10982 | ** |
10983 | ** If no row with matching primary key values is found in the database, |
10984 | ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] |
10985 | ** passed as the second argument. |
10986 | ** |
10987 | ** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT |
10988 | ** (which can only happen if a foreign key constraint is violated), the |
10989 | ** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT] |
10990 | ** passed as the second argument. This includes the case where the DELETE |
10991 | ** operation is attempted because an earlier call to the conflict handler |
10992 | ** function returned [SQLITE_CHANGESET_REPLACE]. |
10993 | ** |
10994 | ** <dt>INSERT Changes<dd> |
10995 | ** For each INSERT change, an attempt is made to insert the new row into |
10996 | ** the database. If the changeset row contains fewer fields than the |
10997 | ** database table, the trailing fields are populated with their default |
10998 | ** values. |
10999 | ** |
11000 | ** If the attempt to insert the row fails because the database already |
11001 | ** contains a row with the same primary key values, the conflict handler |
11002 | ** function is invoked with the second argument set to |
11003 | ** [SQLITE_CHANGESET_CONFLICT]. |
11004 | ** |
11005 | ** If the attempt to insert the row fails because of some other constraint |
11006 | ** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is |
11007 | ** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT]. |
11008 | ** This includes the case where the INSERT operation is re-attempted because |
11009 | ** an earlier call to the conflict handler function returned |
11010 | ** [SQLITE_CHANGESET_REPLACE]. |
11011 | ** |
11012 | ** <dt>UPDATE Changes<dd> |
11013 | ** For each UPDATE change, the function checks if the target database |
11014 | ** contains a row with the same primary key value (or values) as the |
11015 | ** original row values stored in the changeset. If it does, and the values |
11016 | ** stored in all modified non-primary key columns also match the values |
11017 | ** stored in the changeset the row is updated within the target database. |
11018 | ** |
11019 | ** If a row with matching primary key values is found, but one or more of |
11020 | ** the modified non-primary key fields contains a value different from an |
11021 | ** original row value stored in the changeset, the conflict-handler function |
11022 | ** is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since |
11023 | ** UPDATE changes only contain values for non-primary key fields that are |
11024 | ** to be modified, only those fields need to match the original values to |
11025 | ** avoid the SQLITE_CHANGESET_DATA conflict-handler callback. |
11026 | ** |
11027 | ** If no row with matching primary key values is found in the database, |
11028 | ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] |
11029 | ** passed as the second argument. |
11030 | ** |
11031 | ** If the UPDATE operation is attempted, but SQLite returns |
11032 | ** SQLITE_CONSTRAINT, the conflict-handler function is invoked with |
11033 | ** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument. |
11034 | ** This includes the case where the UPDATE operation is attempted after |
11035 | ** an earlier call to the conflict handler function returned |
11036 | ** [SQLITE_CHANGESET_REPLACE]. |
11037 | ** </dl> |
11038 | ** |
11039 | ** It is safe to execute SQL statements, including those that write to the |
11040 | ** table that the callback related to, from within the xConflict callback. |
11041 | ** This can be used to further customize the application's conflict |
11042 | ** resolution strategy. |
11043 | ** |
11044 | ** All changes made by these functions are enclosed in a savepoint transaction. |
11045 | ** If any other error (aside from a constraint failure when attempting to |
11046 | ** write to the target database) occurs, then the savepoint transaction is |
11047 | ** rolled back, restoring the target database to its original state, and an |
11048 | ** SQLite error code returned. |
11049 | ** |
11050 | ** If the output parameters (ppRebase) and (pnRebase) are non-NULL and |
11051 | ** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2() |
11052 | ** may set (*ppRebase) to point to a "rebase" that may be used with the |
11053 | ** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase) |
11054 | ** is set to the size of the buffer in bytes. It is the responsibility of the |
11055 | ** caller to eventually free any such buffer using sqlite3_free(). The buffer |
11056 | ** is only allocated and populated if one or more conflicts were encountered |
11057 | ** while applying the patchset. See comments surrounding the sqlite3_rebaser |
11058 | ** APIs for further details. |
11059 | ** |
11060 | ** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent |
11061 | ** may be modified by passing a combination of |
11062 | ** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter. |
11063 | ** |
11064 | ** Note that the sqlite3changeset_apply_v2() API is still <b>experimental</b> |
11065 | ** and therefore subject to change. |
11066 | */ |
11067 | SQLITE_API int sqlite3changeset_apply( |
11068 | sqlite3 *db, /* Apply change to "main" db of this handle */ |
11069 | int nChangeset, /* Size of changeset in bytes */ |
11070 | void *pChangeset, /* Changeset blob */ |
11071 | int(*xFilter)( |
11072 | void *pCtx, /* Copy of sixth arg to _apply() */ |
11073 | const char *zTab /* Table name */ |
11074 | ), |
11075 | int(*xConflict)( |
11076 | void *pCtx, /* Copy of sixth arg to _apply() */ |
11077 | int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ |
11078 | sqlite3_changeset_iter *p /* Handle describing change and conflict */ |
11079 | ), |
11080 | void *pCtx /* First argument passed to xConflict */ |
11081 | ); |
11082 | SQLITE_API int sqlite3changeset_apply_v2( |
11083 | sqlite3 *db, /* Apply change to "main" db of this handle */ |
11084 | int nChangeset, /* Size of changeset in bytes */ |
11085 | void *pChangeset, /* Changeset blob */ |
11086 | int(*xFilter)( |
11087 | void *pCtx, /* Copy of sixth arg to _apply() */ |
11088 | const char *zTab /* Table name */ |
11089 | ), |
11090 | int(*xConflict)( |
11091 | void *pCtx, /* Copy of sixth arg to _apply() */ |
11092 | int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ |
11093 | sqlite3_changeset_iter *p /* Handle describing change and conflict */ |
11094 | ), |
11095 | void *pCtx, /* First argument passed to xConflict */ |
11096 | void **ppRebase, int *pnRebase, /* OUT: Rebase data */ |
11097 | int flags /* SESSION_CHANGESETAPPLY_* flags */ |
11098 | ); |
11099 | |
11100 | /* |
11101 | ** CAPI3REF: Flags for sqlite3changeset_apply_v2 |
11102 | ** |
11103 | ** The following flags may passed via the 9th parameter to |
11104 | ** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]: |
11105 | ** |
11106 | ** <dl> |
11107 | ** <dt>SQLITE_CHANGESETAPPLY_NOSAVEPOINT <dd> |
11108 | ** Usually, the sessions module encloses all operations performed by |
11109 | ** a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The |
11110 | ** SAVEPOINT is committed if the changeset or patchset is successfully |
11111 | ** applied, or rolled back if an error occurs. Specifying this flag |
11112 | ** causes the sessions module to omit this savepoint. In this case, if the |
11113 | ** caller has an open transaction or savepoint when apply_v2() is called, |
11114 | ** it may revert the partially applied changeset by rolling it back. |
11115 | ** |
11116 | ** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd> |
11117 | ** Invert the changeset before applying it. This is equivalent to inverting |
11118 | ** a changeset using sqlite3changeset_invert() before applying it. It is |
11119 | ** an error to specify this flag with a patchset. |
11120 | */ |
11121 | #define SQLITE_CHANGESETAPPLY_NOSAVEPOINT 0x0001 |
11122 | #define SQLITE_CHANGESETAPPLY_INVERT 0x0002 |
11123 | |
11124 | /* |
11125 | ** CAPI3REF: Constants Passed To The Conflict Handler |
11126 | ** |
11127 | ** Values that may be passed as the second argument to a conflict-handler. |
11128 | ** |
11129 | ** <dl> |
11130 | ** <dt>SQLITE_CHANGESET_DATA<dd> |
11131 | ** The conflict handler is invoked with CHANGESET_DATA as the second argument |
11132 | ** when processing a DELETE or UPDATE change if a row with the required |
11133 | ** PRIMARY KEY fields is present in the database, but one or more other |
11134 | ** (non primary-key) fields modified by the update do not contain the |
11135 | ** expected "before" values. |
11136 | ** |
11137 | ** The conflicting row, in this case, is the database row with the matching |
11138 | ** primary key. |
11139 | ** |
11140 | ** <dt>SQLITE_CHANGESET_NOTFOUND<dd> |
11141 | ** The conflict handler is invoked with CHANGESET_NOTFOUND as the second |
11142 | ** argument when processing a DELETE or UPDATE change if a row with the |
11143 | ** required PRIMARY KEY fields is not present in the database. |
11144 | ** |
11145 | ** There is no conflicting row in this case. The results of invoking the |
11146 | ** sqlite3changeset_conflict() API are undefined. |
11147 | ** |
11148 | ** <dt>SQLITE_CHANGESET_CONFLICT<dd> |
11149 | ** CHANGESET_CONFLICT is passed as the second argument to the conflict |
11150 | ** handler while processing an INSERT change if the operation would result |
11151 | ** in duplicate primary key values. |
11152 | ** |
11153 | ** The conflicting row in this case is the database row with the matching |
11154 | ** primary key. |
11155 | ** |
11156 | ** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd> |
11157 | ** If foreign key handling is enabled, and applying a changeset leaves the |
11158 | ** database in a state containing foreign key violations, the conflict |
11159 | ** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument |
11160 | ** exactly once before the changeset is committed. If the conflict handler |
11161 | ** returns CHANGESET_OMIT, the changes, including those that caused the |
11162 | ** foreign key constraint violation, are committed. Or, if it returns |
11163 | ** CHANGESET_ABORT, the changeset is rolled back. |
11164 | ** |
11165 | ** No current or conflicting row information is provided. The only function |
11166 | ** it is possible to call on the supplied sqlite3_changeset_iter handle |
11167 | ** is sqlite3changeset_fk_conflicts(). |
11168 | ** |
11169 | ** <dt>SQLITE_CHANGESET_CONSTRAINT<dd> |
11170 | ** If any other constraint violation occurs while applying a change (i.e. |
11171 | ** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is |
11172 | ** invoked with CHANGESET_CONSTRAINT as the second argument. |
11173 | ** |
11174 | ** There is no conflicting row in this case. The results of invoking the |
11175 | ** sqlite3changeset_conflict() API are undefined. |
11176 | ** |
11177 | ** </dl> |
11178 | */ |
11179 | #define SQLITE_CHANGESET_DATA 1 |
11180 | #define SQLITE_CHANGESET_NOTFOUND 2 |
11181 | #define SQLITE_CHANGESET_CONFLICT 3 |
11182 | #define SQLITE_CHANGESET_CONSTRAINT 4 |
11183 | #define SQLITE_CHANGESET_FOREIGN_KEY 5 |
11184 | |
11185 | /* |
11186 | ** CAPI3REF: Constants Returned By The Conflict Handler |
11187 | ** |
11188 | ** A conflict handler callback must return one of the following three values. |
11189 | ** |
11190 | ** <dl> |
11191 | ** <dt>SQLITE_CHANGESET_OMIT<dd> |
11192 | ** If a conflict handler returns this value no special action is taken. The |
11193 | ** change that caused the conflict is not applied. The session module |
11194 | ** continues to the next change in the changeset. |
11195 | ** |
11196 | ** <dt>SQLITE_CHANGESET_REPLACE<dd> |
11197 | ** This value may only be returned if the second argument to the conflict |
11198 | ** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this |
11199 | ** is not the case, any changes applied so far are rolled back and the |
11200 | ** call to sqlite3changeset_apply() returns SQLITE_MISUSE. |
11201 | ** |
11202 | ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict |
11203 | ** handler, then the conflicting row is either updated or deleted, depending |
11204 | ** on the type of change. |
11205 | ** |
11206 | ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict |
11207 | ** handler, then the conflicting row is removed from the database and a |
11208 | ** second attempt to apply the change is made. If this second attempt fails, |
11209 | ** the original row is restored to the database before continuing. |
11210 | ** |
11211 | ** <dt>SQLITE_CHANGESET_ABORT<dd> |
11212 | ** If this value is returned, any changes applied so far are rolled back |
11213 | ** and the call to sqlite3changeset_apply() returns SQLITE_ABORT. |
11214 | ** </dl> |
11215 | */ |
11216 | #define SQLITE_CHANGESET_OMIT 0 |
11217 | #define SQLITE_CHANGESET_REPLACE 1 |
11218 | #define SQLITE_CHANGESET_ABORT 2 |
11219 | |
11220 | /* |
11221 | ** CAPI3REF: Rebasing changesets |
11222 | ** EXPERIMENTAL |
11223 | ** |
11224 | ** Suppose there is a site hosting a database in state S0. And that |
11225 | ** modifications are made that move that database to state S1 and a |
11226 | ** changeset recorded (the "local" changeset). Then, a changeset based |
11227 | ** on S0 is received from another site (the "remote" changeset) and |
11228 | ** applied to the database. The database is then in state |
11229 | ** (S1+"remote"), where the exact state depends on any conflict |
11230 | ** resolution decisions (OMIT or REPLACE) made while applying "remote". |
11231 | ** Rebasing a changeset is to update it to take those conflict |
11232 | ** resolution decisions into account, so that the same conflicts |
11233 | ** do not have to be resolved elsewhere in the network. |
11234 | ** |
11235 | ** For example, if both the local and remote changesets contain an |
11236 | ** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)": |
11237 | ** |
11238 | ** local: INSERT INTO t1 VALUES(1, 'v1'); |
11239 | ** remote: INSERT INTO t1 VALUES(1, 'v2'); |
11240 | ** |
11241 | ** and the conflict resolution is REPLACE, then the INSERT change is |
11242 | ** removed from the local changeset (it was overridden). Or, if the |
11243 | ** conflict resolution was "OMIT", then the local changeset is modified |
11244 | ** to instead contain: |
11245 | ** |
11246 | ** UPDATE t1 SET b = 'v2' WHERE a=1; |
11247 | ** |
11248 | ** Changes within the local changeset are rebased as follows: |
11249 | ** |
11250 | ** <dl> |
11251 | ** <dt>Local INSERT<dd> |
11252 | ** This may only conflict with a remote INSERT. If the conflict |
11253 | ** resolution was OMIT, then add an UPDATE change to the rebased |
11254 | ** changeset. Or, if the conflict resolution was REPLACE, add |
11255 | ** nothing to the rebased changeset. |
11256 | ** |
11257 | ** <dt>Local DELETE<dd> |
11258 | ** This may conflict with a remote UPDATE or DELETE. In both cases the |
11259 | ** only possible resolution is OMIT. If the remote operation was a |
11260 | ** DELETE, then add no change to the rebased changeset. If the remote |
11261 | ** operation was an UPDATE, then the old.* fields of change are updated |
11262 | ** to reflect the new.* values in the UPDATE. |
11263 | ** |
11264 | ** <dt>Local UPDATE<dd> |
11265 | ** This may conflict with a remote UPDATE or DELETE. If it conflicts |
11266 | ** with a DELETE, and the conflict resolution was OMIT, then the update |
11267 | ** is changed into an INSERT. Any undefined values in the new.* record |
11268 | ** from the update change are filled in using the old.* values from |
11269 | ** the conflicting DELETE. Or, if the conflict resolution was REPLACE, |
11270 | ** the UPDATE change is simply omitted from the rebased changeset. |
11271 | ** |
11272 | ** If conflict is with a remote UPDATE and the resolution is OMIT, then |
11273 | ** the old.* values are rebased using the new.* values in the remote |
11274 | ** change. Or, if the resolution is REPLACE, then the change is copied |
11275 | ** into the rebased changeset with updates to columns also updated by |
11276 | ** the conflicting remote UPDATE removed. If this means no columns would |
11277 | ** be updated, the change is omitted. |
11278 | ** </dl> |
11279 | ** |
11280 | ** A local change may be rebased against multiple remote changes |
11281 | ** simultaneously. If a single key is modified by multiple remote |
11282 | ** changesets, they are combined as follows before the local changeset |
11283 | ** is rebased: |
11284 | ** |
11285 | ** <ul> |
11286 | ** <li> If there has been one or more REPLACE resolutions on a |
11287 | ** key, it is rebased according to a REPLACE. |
11288 | ** |
11289 | ** <li> If there have been no REPLACE resolutions on a key, then |
11290 | ** the local changeset is rebased according to the most recent |
11291 | ** of the OMIT resolutions. |
11292 | ** </ul> |
11293 | ** |
11294 | ** Note that conflict resolutions from multiple remote changesets are |
11295 | ** combined on a per-field basis, not per-row. This means that in the |
11296 | ** case of multiple remote UPDATE operations, some fields of a single |
11297 | ** local change may be rebased for REPLACE while others are rebased for |
11298 | ** OMIT. |
11299 | ** |
11300 | ** In order to rebase a local changeset, the remote changeset must first |
11301 | ** be applied to the local database using sqlite3changeset_apply_v2() and |
11302 | ** the buffer of rebase information captured. Then: |
11303 | ** |
11304 | ** <ol> |
11305 | ** <li> An sqlite3_rebaser object is created by calling |
11306 | ** sqlite3rebaser_create(). |
11307 | ** <li> The new object is configured with the rebase buffer obtained from |
11308 | ** sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure(). |
11309 | ** If the local changeset is to be rebased against multiple remote |
11310 | ** changesets, then sqlite3rebaser_configure() should be called |
11311 | ** multiple times, in the same order that the multiple |
11312 | ** sqlite3changeset_apply_v2() calls were made. |
11313 | ** <li> Each local changeset is rebased by calling sqlite3rebaser_rebase(). |
11314 | ** <li> The sqlite3_rebaser object is deleted by calling |
11315 | ** sqlite3rebaser_delete(). |
11316 | ** </ol> |
11317 | */ |
11318 | typedef struct sqlite3_rebaser sqlite3_rebaser; |
11319 | |
11320 | /* |
11321 | ** CAPI3REF: Create a changeset rebaser object. |
11322 | ** EXPERIMENTAL |
11323 | ** |
11324 | ** Allocate a new changeset rebaser object. If successful, set (*ppNew) to |
11325 | ** point to the new object and return SQLITE_OK. Otherwise, if an error |
11326 | ** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew) |
11327 | ** to NULL. |
11328 | */ |
11329 | SQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew); |
11330 | |
11331 | /* |
11332 | ** CAPI3REF: Configure a changeset rebaser object. |
11333 | ** EXPERIMENTAL |
11334 | ** |
11335 | ** Configure the changeset rebaser object to rebase changesets according |
11336 | ** to the conflict resolutions described by buffer pRebase (size nRebase |
11337 | ** bytes), which must have been obtained from a previous call to |
11338 | ** sqlite3changeset_apply_v2(). |
11339 | */ |
11340 | SQLITE_API int sqlite3rebaser_configure( |
11341 | sqlite3_rebaser*, |
11342 | int nRebase, const void *pRebase |
11343 | ); |
11344 | |
11345 | /* |
11346 | ** CAPI3REF: Rebase a changeset |
11347 | ** EXPERIMENTAL |
11348 | ** |
11349 | ** Argument pIn must point to a buffer containing a changeset nIn bytes |
11350 | ** in size. This function allocates and populates a buffer with a copy |
11351 | ** of the changeset rebased according to the configuration of the |
11352 | ** rebaser object passed as the first argument. If successful, (*ppOut) |
11353 | ** is set to point to the new buffer containing the rebased changeset and |
11354 | ** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the |
11355 | ** responsibility of the caller to eventually free the new buffer using |
11356 | ** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut) |
11357 | ** are set to zero and an SQLite error code returned. |
11358 | */ |
11359 | SQLITE_API int sqlite3rebaser_rebase( |
11360 | sqlite3_rebaser*, |
11361 | int nIn, const void *pIn, |
11362 | int *pnOut, void **ppOut |
11363 | ); |
11364 | |
11365 | /* |
11366 | ** CAPI3REF: Delete a changeset rebaser object. |
11367 | ** EXPERIMENTAL |
11368 | ** |
11369 | ** Delete the changeset rebaser object and all associated resources. There |
11370 | ** should be one call to this function for each successful invocation |
11371 | ** of sqlite3rebaser_create(). |
11372 | */ |
11373 | SQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p); |
11374 | |
11375 | /* |
11376 | ** CAPI3REF: Streaming Versions of API functions. |
11377 | ** |
11378 | ** The six streaming API xxx_strm() functions serve similar purposes to the |
11379 | ** corresponding non-streaming API functions: |
11380 | ** |
11381 | ** <table border=1 style="margin-left:8ex;margin-right:8ex"> |
11382 | ** <tr><th>Streaming function<th>Non-streaming equivalent</th> |
11383 | ** <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply] |
11384 | ** <tr><td>sqlite3changeset_apply_strm_v2<td>[sqlite3changeset_apply_v2] |
11385 | ** <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat] |
11386 | ** <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert] |
11387 | ** <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start] |
11388 | ** <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset] |
11389 | ** <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset] |
11390 | ** </table> |
11391 | ** |
11392 | ** Non-streaming functions that accept changesets (or patchsets) as input |
11393 | ** require that the entire changeset be stored in a single buffer in memory. |
11394 | ** Similarly, those that return a changeset or patchset do so by returning |
11395 | ** a pointer to a single large buffer allocated using sqlite3_malloc(). |
11396 | ** Normally this is convenient. However, if an application running in a |
11397 | ** low-memory environment is required to handle very large changesets, the |
11398 | ** large contiguous memory allocations required can become onerous. |
11399 | ** |
11400 | ** In order to avoid this problem, instead of a single large buffer, input |
11401 | ** is passed to a streaming API functions by way of a callback function that |
11402 | ** the sessions module invokes to incrementally request input data as it is |
11403 | ** required. In all cases, a pair of API function parameters such as |
11404 | ** |
11405 | ** <pre> |
11406 | ** int nChangeset, |
11407 | ** void *pChangeset, |
11408 | ** </pre> |
11409 | ** |
11410 | ** Is replaced by: |
11411 | ** |
11412 | ** <pre> |
11413 | ** int (*xInput)(void *pIn, void *pData, int *pnData), |
11414 | ** void *pIn, |
11415 | ** </pre> |
11416 | ** |
11417 | ** Each time the xInput callback is invoked by the sessions module, the first |
11418 | ** argument passed is a copy of the supplied pIn context pointer. The second |
11419 | ** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no |
11420 | ** error occurs the xInput method should copy up to (*pnData) bytes of data |
11421 | ** into the buffer and set (*pnData) to the actual number of bytes copied |
11422 | ** before returning SQLITE_OK. If the input is completely exhausted, (*pnData) |
11423 | ** should be set to zero to indicate this. Or, if an error occurs, an SQLite |
11424 | ** error code should be returned. In all cases, if an xInput callback returns |
11425 | ** an error, all processing is abandoned and the streaming API function |
11426 | ** returns a copy of the error code to the caller. |
11427 | ** |
11428 | ** In the case of sqlite3changeset_start_strm(), the xInput callback may be |
11429 | ** invoked by the sessions module at any point during the lifetime of the |
11430 | ** iterator. If such an xInput callback returns an error, the iterator enters |
11431 | ** an error state, whereby all subsequent calls to iterator functions |
11432 | ** immediately fail with the same error code as returned by xInput. |
11433 | ** |
11434 | ** Similarly, streaming API functions that return changesets (or patchsets) |
11435 | ** return them in chunks by way of a callback function instead of via a |
11436 | ** pointer to a single large buffer. In this case, a pair of parameters such |
11437 | ** as: |
11438 | ** |
11439 | ** <pre> |
11440 | ** int *pnChangeset, |
11441 | ** void **ppChangeset, |
11442 | ** </pre> |
11443 | ** |
11444 | ** Is replaced by: |
11445 | ** |
11446 | ** <pre> |
11447 | ** int (*xOutput)(void *pOut, const void *pData, int nData), |
11448 | ** void *pOut |
11449 | ** </pre> |
11450 | ** |
11451 | ** The xOutput callback is invoked zero or more times to return data to |
11452 | ** the application. The first parameter passed to each call is a copy of the |
11453 | ** pOut pointer supplied by the application. The second parameter, pData, |
11454 | ** points to a buffer nData bytes in size containing the chunk of output |
11455 | ** data being returned. If the xOutput callback successfully processes the |
11456 | ** supplied data, it should return SQLITE_OK to indicate success. Otherwise, |
11457 | ** it should return some other SQLite error code. In this case processing |
11458 | ** is immediately abandoned and the streaming API function returns a copy |
11459 | ** of the xOutput error code to the application. |
11460 | ** |
11461 | ** The sessions module never invokes an xOutput callback with the third |
11462 | ** parameter set to a value less than or equal to zero. Other than this, |
11463 | ** no guarantees are made as to the size of the chunks of data returned. |
11464 | */ |
11465 | SQLITE_API int sqlite3changeset_apply_strm( |
11466 | sqlite3 *db, /* Apply change to "main" db of this handle */ |
11467 | int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ |
11468 | void *pIn, /* First arg for xInput */ |
11469 | int(*xFilter)( |
11470 | void *pCtx, /* Copy of sixth arg to _apply() */ |
11471 | const char *zTab /* Table name */ |
11472 | ), |
11473 | int(*xConflict)( |
11474 | void *pCtx, /* Copy of sixth arg to _apply() */ |
11475 | int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ |
11476 | sqlite3_changeset_iter *p /* Handle describing change and conflict */ |
11477 | ), |
11478 | void *pCtx /* First argument passed to xConflict */ |
11479 | ); |
11480 | SQLITE_API int sqlite3changeset_apply_v2_strm( |
11481 | sqlite3 *db, /* Apply change to "main" db of this handle */ |
11482 | int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ |
11483 | void *pIn, /* First arg for xInput */ |
11484 | int(*xFilter)( |
11485 | void *pCtx, /* Copy of sixth arg to _apply() */ |
11486 | const char *zTab /* Table name */ |
11487 | ), |
11488 | int(*xConflict)( |
11489 | void *pCtx, /* Copy of sixth arg to _apply() */ |
11490 | int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ |
11491 | sqlite3_changeset_iter *p /* Handle describing change and conflict */ |
11492 | ), |
11493 | void *pCtx, /* First argument passed to xConflict */ |
11494 | void **ppRebase, int *pnRebase, |
11495 | int flags |
11496 | ); |
11497 | SQLITE_API int sqlite3changeset_concat_strm( |
11498 | int (*xInputA)(void *pIn, void *pData, int *pnData), |
11499 | void *pInA, |
11500 | int (*xInputB)(void *pIn, void *pData, int *pnData), |
11501 | void *pInB, |
11502 | int (*xOutput)(void *pOut, const void *pData, int nData), |
11503 | void *pOut |
11504 | ); |
11505 | SQLITE_API int sqlite3changeset_invert_strm( |
11506 | int (*xInput)(void *pIn, void *pData, int *pnData), |
11507 | void *pIn, |
11508 | int (*xOutput)(void *pOut, const void *pData, int nData), |
11509 | void *pOut |
11510 | ); |
11511 | SQLITE_API int sqlite3changeset_start_strm( |
11512 | sqlite3_changeset_iter **pp, |
11513 | int (*xInput)(void *pIn, void *pData, int *pnData), |
11514 | void *pIn |
11515 | ); |
11516 | SQLITE_API int sqlite3changeset_start_v2_strm( |
11517 | sqlite3_changeset_iter **pp, |
11518 | int (*xInput)(void *pIn, void *pData, int *pnData), |
11519 | void *pIn, |
11520 | int flags |
11521 | ); |
11522 | SQLITE_API int sqlite3session_changeset_strm( |
11523 | sqlite3_session *pSession, |
11524 | int (*xOutput)(void *pOut, const void *pData, int nData), |
11525 | void *pOut |
11526 | ); |
11527 | SQLITE_API int sqlite3session_patchset_strm( |
11528 | sqlite3_session *pSession, |
11529 | int (*xOutput)(void *pOut, const void *pData, int nData), |
11530 | void *pOut |
11531 | ); |
11532 | SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*, |
11533 | int (*xInput)(void *pIn, void *pData, int *pnData), |
11534 | void *pIn |
11535 | ); |
11536 | SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*, |
11537 | int (*xOutput)(void *pOut, const void *pData, int nData), |
11538 | void *pOut |
11539 | ); |
11540 | SQLITE_API int sqlite3rebaser_rebase_strm( |
11541 | sqlite3_rebaser *pRebaser, |
11542 | int (*xInput)(void *pIn, void *pData, int *pnData), |
11543 | void *pIn, |
11544 | int (*xOutput)(void *pOut, const void *pData, int nData), |
11545 | void *pOut |
11546 | ); |
11547 | |
11548 | /* |
11549 | ** CAPI3REF: Configure global parameters |
11550 | ** |
11551 | ** The sqlite3session_config() interface is used to make global configuration |
11552 | ** changes to the sessions module in order to tune it to the specific needs |
11553 | ** of the application. |
11554 | ** |
11555 | ** The sqlite3session_config() interface is not threadsafe. If it is invoked |
11556 | ** while any other thread is inside any other sessions method then the |
11557 | ** results are undefined. Furthermore, if it is invoked after any sessions |
11558 | ** related objects have been created, the results are also undefined. |
11559 | ** |
11560 | ** The first argument to the sqlite3session_config() function must be one |
11561 | ** of the SQLITE_SESSION_CONFIG_XXX constants defined below. The |
11562 | ** interpretation of the (void*) value passed as the second parameter and |
11563 | ** the effect of calling this function depends on the value of the first |
11564 | ** parameter. |
11565 | ** |
11566 | ** <dl> |
11567 | ** <dt>SQLITE_SESSION_CONFIG_STRMSIZE<dd> |
11568 | ** By default, the sessions module streaming interfaces attempt to input |
11569 | ** and output data in approximately 1 KiB chunks. This operand may be used |
11570 | ** to set and query the value of this configuration setting. The pointer |
11571 | ** passed as the second argument must point to a value of type (int). |
11572 | ** If this value is greater than 0, it is used as the new streaming data |
11573 | ** chunk size for both input and output. Before returning, the (int) value |
11574 | ** pointed to by pArg is set to the final value of the streaming interface |
11575 | ** chunk size. |
11576 | ** </dl> |
11577 | ** |
11578 | ** This function returns SQLITE_OK if successful, or an SQLite error code |
11579 | ** otherwise. |
11580 | */ |
11581 | SQLITE_API int sqlite3session_config(int op, void *pArg); |
11582 | |
11583 | /* |
11584 | ** CAPI3REF: Values for sqlite3session_config(). |
11585 | */ |
11586 | #define SQLITE_SESSION_CONFIG_STRMSIZE 1 |
11587 | |
11588 | /* |
11589 | ** Make sure we can call this stuff from C++. |
11590 | */ |
11591 | #ifdef __cplusplus |
11592 | } |
11593 | #endif |
11594 | |
11595 | #endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */ |
11596 | |
11597 | /******** End of sqlite3session.h *********/ |
11598 | /******** Begin file fts5.h *********/ |
11599 | /* |
11600 | ** 2014 May 31 |
11601 | ** |
11602 | ** The author disclaims copyright to this source code. In place of |
11603 | ** a legal notice, here is a blessing: |
11604 | ** |
11605 | ** May you do good and not evil. |
11606 | ** May you find forgiveness for yourself and forgive others. |
11607 | ** May you share freely, never taking more than you give. |
11608 | ** |
11609 | ****************************************************************************** |
11610 | ** |
11611 | ** Interfaces to extend FTS5. Using the interfaces defined in this file, |
11612 | ** FTS5 may be extended with: |
11613 | ** |
11614 | ** * custom tokenizers, and |
11615 | ** * custom auxiliary functions. |
11616 | */ |
11617 | |
11618 | |
11619 | #ifndef _FTS5_H |
11620 | #define _FTS5_H |
11621 | |
11622 | |
11623 | #ifdef __cplusplus |
11624 | extern "C" { |
11625 | #endif |
11626 | |
11627 | /************************************************************************* |
11628 | ** CUSTOM AUXILIARY FUNCTIONS |
11629 | ** |
11630 | ** Virtual table implementations may overload SQL functions by implementing |
11631 | ** the sqlite3_module.xFindFunction() method. |
11632 | */ |
11633 | |
11634 | typedef struct Fts5ExtensionApi Fts5ExtensionApi; |
11635 | typedef struct Fts5Context Fts5Context; |
11636 | typedef struct Fts5PhraseIter Fts5PhraseIter; |
11637 | |
11638 | typedef void (*fts5_extension_function)( |
11639 | const Fts5ExtensionApi *pApi, /* API offered by current FTS version */ |
11640 | Fts5Context *pFts, /* First arg to pass to pApi functions */ |
11641 | sqlite3_context *pCtx, /* Context for returning result/error */ |
11642 | int nVal, /* Number of values in apVal[] array */ |
11643 | sqlite3_value **apVal /* Array of trailing arguments */ |
11644 | ); |
11645 | |
11646 | struct Fts5PhraseIter { |
11647 | const unsigned char *a; |
11648 | const unsigned char *b; |
11649 | }; |
11650 | |
11651 | /* |
11652 | ** EXTENSION API FUNCTIONS |
11653 | ** |
11654 | ** xUserData(pFts): |
11655 | ** Return a copy of the context pointer the extension function was |
11656 | ** registered with. |
11657 | ** |
11658 | ** xColumnTotalSize(pFts, iCol, pnToken): |
11659 | ** If parameter iCol is less than zero, set output variable *pnToken |
11660 | ** to the total number of tokens in the FTS5 table. Or, if iCol is |
11661 | ** non-negative but less than the number of columns in the table, return |
11662 | ** the total number of tokens in column iCol, considering all rows in |
11663 | ** the FTS5 table. |
11664 | ** |
11665 | ** If parameter iCol is greater than or equal to the number of columns |
11666 | ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. |
11667 | ** an OOM condition or IO error), an appropriate SQLite error code is |
11668 | ** returned. |
11669 | ** |
11670 | ** xColumnCount(pFts): |
11671 | ** Return the number of columns in the table. |
11672 | ** |
11673 | ** xColumnSize(pFts, iCol, pnToken): |
11674 | ** If parameter iCol is less than zero, set output variable *pnToken |
11675 | ** to the total number of tokens in the current row. Or, if iCol is |
11676 | ** non-negative but less than the number of columns in the table, set |
11677 | ** *pnToken to the number of tokens in column iCol of the current row. |
11678 | ** |
11679 | ** If parameter iCol is greater than or equal to the number of columns |
11680 | ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. |
11681 | ** an OOM condition or IO error), an appropriate SQLite error code is |
11682 | ** returned. |
11683 | ** |
11684 | ** This function may be quite inefficient if used with an FTS5 table |
11685 | ** created with the "columnsize=0" option. |
11686 | ** |
11687 | ** xColumnText: |
11688 | ** This function attempts to retrieve the text of column iCol of the |
11689 | ** current document. If successful, (*pz) is set to point to a buffer |
11690 | ** containing the text in utf-8 encoding, (*pn) is set to the size in bytes |
11691 | ** (not characters) of the buffer and SQLITE_OK is returned. Otherwise, |
11692 | ** if an error occurs, an SQLite error code is returned and the final values |
11693 | ** of (*pz) and (*pn) are undefined. |
11694 | ** |
11695 | ** xPhraseCount: |
11696 | ** Returns the number of phrases in the current query expression. |
11697 | ** |
11698 | ** xPhraseSize: |
11699 | ** Returns the number of tokens in phrase iPhrase of the query. Phrases |
11700 | ** are numbered starting from zero. |
11701 | ** |
11702 | ** xInstCount: |
11703 | ** Set *pnInst to the total number of occurrences of all phrases within |
11704 | ** the query within the current row. Return SQLITE_OK if successful, or |
11705 | ** an error code (i.e. SQLITE_NOMEM) if an error occurs. |
11706 | ** |
11707 | ** This API can be quite slow if used with an FTS5 table created with the |
11708 | ** "detail=none" or "detail=column" option. If the FTS5 table is created |
11709 | ** with either "detail=none" or "detail=column" and "content=" option |
11710 | ** (i.e. if it is a contentless table), then this API always returns 0. |
11711 | ** |
11712 | ** xInst: |
11713 | ** Query for the details of phrase match iIdx within the current row. |
11714 | ** Phrase matches are numbered starting from zero, so the iIdx argument |
11715 | ** should be greater than or equal to zero and smaller than the value |
11716 | ** output by xInstCount(). |
11717 | ** |
11718 | ** Usually, output parameter *piPhrase is set to the phrase number, *piCol |
11719 | ** to the column in which it occurs and *piOff the token offset of the |
11720 | ** first token of the phrase. Returns SQLITE_OK if successful, or an error |
11721 | ** code (i.e. SQLITE_NOMEM) if an error occurs. |
11722 | ** |
11723 | ** This API can be quite slow if used with an FTS5 table created with the |
11724 | ** "detail=none" or "detail=column" option. |
11725 | ** |
11726 | ** xRowid: |
11727 | ** Returns the rowid of the current row. |
11728 | ** |
11729 | ** xTokenize: |
11730 | ** Tokenize text using the tokenizer belonging to the FTS5 table. |
11731 | ** |
11732 | ** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback): |
11733 | ** This API function is used to query the FTS table for phrase iPhrase |
11734 | ** of the current query. Specifically, a query equivalent to: |
11735 | ** |
11736 | ** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid |
11737 | ** |
11738 | ** with $p set to a phrase equivalent to the phrase iPhrase of the |
11739 | ** current query is executed. Any column filter that applies to |
11740 | ** phrase iPhrase of the current query is included in $p. For each |
11741 | ** row visited, the callback function passed as the fourth argument |
11742 | ** is invoked. The context and API objects passed to the callback |
11743 | ** function may be used to access the properties of each matched row. |
11744 | ** Invoking Api.xUserData() returns a copy of the pointer passed as |
11745 | ** the third argument to pUserData. |
11746 | ** |
11747 | ** If the callback function returns any value other than SQLITE_OK, the |
11748 | ** query is abandoned and the xQueryPhrase function returns immediately. |
11749 | ** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK. |
11750 | ** Otherwise, the error code is propagated upwards. |
11751 | ** |
11752 | ** If the query runs to completion without incident, SQLITE_OK is returned. |
11753 | ** Or, if some error occurs before the query completes or is aborted by |
11754 | ** the callback, an SQLite error code is returned. |
11755 | ** |
11756 | ** |
11757 | ** xSetAuxdata(pFts5, pAux, xDelete) |
11758 | ** |
11759 | ** Save the pointer passed as the second argument as the extension function's |
11760 | ** "auxiliary data". The pointer may then be retrieved by the current or any |
11761 | ** future invocation of the same fts5 extension function made as part of |
11762 | ** the same MATCH query using the xGetAuxdata() API. |
11763 | ** |
11764 | ** Each extension function is allocated a single auxiliary data slot for |
11765 | ** each FTS query (MATCH expression). If the extension function is invoked |
11766 | ** more than once for a single FTS query, then all invocations share a |
11767 | ** single auxiliary data context. |
11768 | ** |
11769 | ** If there is already an auxiliary data pointer when this function is |
11770 | ** invoked, then it is replaced by the new pointer. If an xDelete callback |
11771 | ** was specified along with the original pointer, it is invoked at this |
11772 | ** point. |
11773 | ** |
11774 | ** The xDelete callback, if one is specified, is also invoked on the |
11775 | ** auxiliary data pointer after the FTS5 query has finished. |
11776 | ** |
11777 | ** If an error (e.g. an OOM condition) occurs within this function, |
11778 | ** the auxiliary data is set to NULL and an error code returned. If the |
11779 | ** xDelete parameter was not NULL, it is invoked on the auxiliary data |
11780 | ** pointer before returning. |
11781 | ** |
11782 | ** |
11783 | ** xGetAuxdata(pFts5, bClear) |
11784 | ** |
11785 | ** Returns the current auxiliary data pointer for the fts5 extension |
11786 | ** function. See the xSetAuxdata() method for details. |
11787 | ** |
11788 | ** If the bClear argument is non-zero, then the auxiliary data is cleared |
11789 | ** (set to NULL) before this function returns. In this case the xDelete, |
11790 | ** if any, is not invoked. |
11791 | ** |
11792 | ** |
11793 | ** xRowCount(pFts5, pnRow) |
11794 | ** |
11795 | ** This function is used to retrieve the total number of rows in the table. |
11796 | ** In other words, the same value that would be returned by: |
11797 | ** |
11798 | ** SELECT count(*) FROM ftstable; |
11799 | ** |
11800 | ** xPhraseFirst() |
11801 | ** This function is used, along with type Fts5PhraseIter and the xPhraseNext |
11802 | ** method, to iterate through all instances of a single query phrase within |
11803 | ** the current row. This is the same information as is accessible via the |
11804 | ** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient |
11805 | ** to use, this API may be faster under some circumstances. To iterate |
11806 | ** through instances of phrase iPhrase, use the following code: |
11807 | ** |
11808 | ** Fts5PhraseIter iter; |
11809 | ** int iCol, iOff; |
11810 | ** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff); |
11811 | ** iCol>=0; |
11812 | ** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff) |
11813 | ** ){ |
11814 | ** // An instance of phrase iPhrase at offset iOff of column iCol |
11815 | ** } |
11816 | ** |
11817 | ** The Fts5PhraseIter structure is defined above. Applications should not |
11818 | ** modify this structure directly - it should only be used as shown above |
11819 | ** with the xPhraseFirst() and xPhraseNext() API methods (and by |
11820 | ** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below). |
11821 | ** |
11822 | ** This API can be quite slow if used with an FTS5 table created with the |
11823 | ** "detail=none" or "detail=column" option. If the FTS5 table is created |
11824 | ** with either "detail=none" or "detail=column" and "content=" option |
11825 | ** (i.e. if it is a contentless table), then this API always iterates |
11826 | ** through an empty set (all calls to xPhraseFirst() set iCol to -1). |
11827 | ** |
11828 | ** xPhraseNext() |
11829 | ** See xPhraseFirst above. |
11830 | ** |
11831 | ** xPhraseFirstColumn() |
11832 | ** This function and xPhraseNextColumn() are similar to the xPhraseFirst() |
11833 | ** and xPhraseNext() APIs described above. The difference is that instead |
11834 | ** of iterating through all instances of a phrase in the current row, these |
11835 | ** APIs are used to iterate through the set of columns in the current row |
11836 | ** that contain one or more instances of a specified phrase. For example: |
11837 | ** |
11838 | ** Fts5PhraseIter iter; |
11839 | ** int iCol; |
11840 | ** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol); |
11841 | ** iCol>=0; |
11842 | ** pApi->xPhraseNextColumn(pFts, &iter, &iCol) |
11843 | ** ){ |
11844 | ** // Column iCol contains at least one instance of phrase iPhrase |
11845 | ** } |
11846 | ** |
11847 | ** This API can be quite slow if used with an FTS5 table created with the |
11848 | ** "detail=none" option. If the FTS5 table is created with either |
11849 | ** "detail=none" "content=" option (i.e. if it is a contentless table), |
11850 | ** then this API always iterates through an empty set (all calls to |
11851 | ** xPhraseFirstColumn() set iCol to -1). |
11852 | ** |
11853 | ** The information accessed using this API and its companion |
11854 | ** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext |
11855 | ** (or xInst/xInstCount). The chief advantage of this API is that it is |
11856 | ** significantly more efficient than those alternatives when used with |
11857 | ** "detail=column" tables. |
11858 | ** |
11859 | ** xPhraseNextColumn() |
11860 | ** See xPhraseFirstColumn above. |
11861 | */ |
11862 | struct Fts5ExtensionApi { |
11863 | int iVersion; /* Currently always set to 3 */ |
11864 | |
11865 | void *(*xUserData)(Fts5Context*); |
11866 | |
11867 | int (*xColumnCount)(Fts5Context*); |
11868 | int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow); |
11869 | int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken); |
11870 | |
11871 | int (*xTokenize)(Fts5Context*, |
11872 | const char *pText, int nText, /* Text to tokenize */ |
11873 | void *pCtx, /* Context passed to xToken() */ |
11874 | int (*xToken)(void*, int, const char*, int, int, int) /* Callback */ |
11875 | ); |
11876 | |
11877 | int (*xPhraseCount)(Fts5Context*); |
11878 | int (*xPhraseSize)(Fts5Context*, int iPhrase); |
11879 | |
11880 | int (*xInstCount)(Fts5Context*, int *pnInst); |
11881 | int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff); |
11882 | |
11883 | sqlite3_int64 (*xRowid)(Fts5Context*); |
11884 | int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn); |
11885 | int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken); |
11886 | |
11887 | int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData, |
11888 | int(*)(const Fts5ExtensionApi*,Fts5Context*,void*) |
11889 | ); |
11890 | int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*)); |
11891 | void *(*xGetAuxdata)(Fts5Context*, int bClear); |
11892 | |
11893 | int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*); |
11894 | void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff); |
11895 | |
11896 | int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*); |
11897 | void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol); |
11898 | }; |
11899 | |
11900 | /* |
11901 | ** CUSTOM AUXILIARY FUNCTIONS |
11902 | *************************************************************************/ |
11903 | |
11904 | /************************************************************************* |
11905 | ** CUSTOM TOKENIZERS |
11906 | ** |
11907 | ** Applications may also register custom tokenizer types. A tokenizer |
11908 | ** is registered by providing fts5 with a populated instance of the |
11909 | ** following structure. All structure methods must be defined, setting |
11910 | ** any member of the fts5_tokenizer struct to NULL leads to undefined |
11911 | ** behaviour. The structure methods are expected to function as follows: |
11912 | ** |
11913 | ** xCreate: |
11914 | ** This function is used to allocate and initialize a tokenizer instance. |
11915 | ** A tokenizer instance is required to actually tokenize text. |
11916 | ** |
11917 | ** The first argument passed to this function is a copy of the (void*) |
11918 | ** pointer provided by the application when the fts5_tokenizer object |
11919 | ** was registered with FTS5 (the third argument to xCreateTokenizer()). |
11920 | ** The second and third arguments are an array of nul-terminated strings |
11921 | ** containing the tokenizer arguments, if any, specified following the |
11922 | ** tokenizer name as part of the CREATE VIRTUAL TABLE statement used |
11923 | ** to create the FTS5 table. |
11924 | ** |
11925 | ** The final argument is an output variable. If successful, (*ppOut) |
11926 | ** should be set to point to the new tokenizer handle and SQLITE_OK |
11927 | ** returned. If an error occurs, some value other than SQLITE_OK should |
11928 | ** be returned. In this case, fts5 assumes that the final value of *ppOut |
11929 | ** is undefined. |
11930 | ** |
11931 | ** xDelete: |
11932 | ** This function is invoked to delete a tokenizer handle previously |
11933 | ** allocated using xCreate(). Fts5 guarantees that this function will |
11934 | ** be invoked exactly once for each successful call to xCreate(). |
11935 | ** |
11936 | ** xTokenize: |
11937 | ** This function is expected to tokenize the nText byte string indicated |
11938 | ** by argument pText. pText may or may not be nul-terminated. The first |
11939 | ** argument passed to this function is a pointer to an Fts5Tokenizer object |
11940 | ** returned by an earlier call to xCreate(). |
11941 | ** |
11942 | ** The second argument indicates the reason that FTS5 is requesting |
11943 | ** tokenization of the supplied text. This is always one of the following |
11944 | ** four values: |
11945 | ** |
11946 | ** <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into |
11947 | ** or removed from the FTS table. The tokenizer is being invoked to |
11948 | ** determine the set of tokens to add to (or delete from) the |
11949 | ** FTS index. |
11950 | ** |
11951 | ** <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed |
11952 | ** against the FTS index. The tokenizer is being called to tokenize |
11953 | ** a bareword or quoted string specified as part of the query. |
11954 | ** |
11955 | ** <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as |
11956 | ** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is |
11957 | ** followed by a "*" character, indicating that the last token |
11958 | ** returned by the tokenizer will be treated as a token prefix. |
11959 | ** |
11960 | ** <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to |
11961 | ** satisfy an fts5_api.xTokenize() request made by an auxiliary |
11962 | ** function. Or an fts5_api.xColumnSize() request made by the same |
11963 | ** on a columnsize=0 database. |
11964 | ** </ul> |
11965 | ** |
11966 | ** For each token in the input string, the supplied callback xToken() must |
11967 | ** be invoked. The first argument to it should be a copy of the pointer |
11968 | ** passed as the second argument to xTokenize(). The third and fourth |
11969 | ** arguments are a pointer to a buffer containing the token text, and the |
11970 | ** size of the token in bytes. The 4th and 5th arguments are the byte offsets |
11971 | ** of the first byte of and first byte immediately following the text from |
11972 | ** which the token is derived within the input. |
11973 | ** |
11974 | ** The second argument passed to the xToken() callback ("tflags") should |
11975 | ** normally be set to 0. The exception is if the tokenizer supports |
11976 | ** synonyms. In this case see the discussion below for details. |
11977 | ** |
11978 | ** FTS5 assumes the xToken() callback is invoked for each token in the |
11979 | ** order that they occur within the input text. |
11980 | ** |
11981 | ** If an xToken() callback returns any value other than SQLITE_OK, then |
11982 | ** the tokenization should be abandoned and the xTokenize() method should |
11983 | ** immediately return a copy of the xToken() return value. Or, if the |
11984 | ** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally, |
11985 | ** if an error occurs with the xTokenize() implementation itself, it |
11986 | ** may abandon the tokenization and return any error code other than |
11987 | ** SQLITE_OK or SQLITE_DONE. |
11988 | ** |
11989 | ** SYNONYM SUPPORT |
11990 | ** |
11991 | ** Custom tokenizers may also support synonyms. Consider a case in which a |
11992 | ** user wishes to query for a phrase such as "first place". Using the |
11993 | ** built-in tokenizers, the FTS5 query 'first + place' will match instances |
11994 | ** of "first place" within the document set, but not alternative forms |
11995 | ** such as "1st place". In some applications, it would be better to match |
11996 | ** all instances of "first place" or "1st place" regardless of which form |
11997 | ** the user specified in the MATCH query text. |
11998 | ** |
11999 | ** There are several ways to approach this in FTS5: |
12000 | ** |
12001 | ** <ol><li> By mapping all synonyms to a single token. In this case, using |
12002 | ** the above example, this means that the tokenizer returns the |
12003 | ** same token for inputs "first" and "1st". Say that token is in |
12004 | ** fact "first", so that when the user inserts the document "I won |
12005 | ** 1st place" entries are added to the index for tokens "i", "won", |
12006 | ** "first" and "place". If the user then queries for '1st + place', |
12007 | ** the tokenizer substitutes "first" for "1st" and the query works |
12008 | ** as expected. |
12009 | ** |
12010 | ** <li> By querying the index for all synonyms of each query term |
12011 | ** separately. In this case, when tokenizing query text, the |
12012 | ** tokenizer may provide multiple synonyms for a single term |
12013 | ** within the document. FTS5 then queries the index for each |
12014 | ** synonym individually. For example, faced with the query: |
12015 | ** |
12016 | ** <codeblock> |
12017 | ** ... MATCH 'first place'</codeblock> |
12018 | ** |
12019 | ** the tokenizer offers both "1st" and "first" as synonyms for the |
12020 | ** first token in the MATCH query and FTS5 effectively runs a query |
12021 | ** similar to: |
12022 | ** |
12023 | ** <codeblock> |
12024 | ** ... MATCH '(first OR 1st) place'</codeblock> |
12025 | ** |
12026 | ** except that, for the purposes of auxiliary functions, the query |
12027 | ** still appears to contain just two phrases - "(first OR 1st)" |
12028 | ** being treated as a single phrase. |
12029 | ** |
12030 | ** <li> By adding multiple synonyms for a single term to the FTS index. |
12031 | ** Using this method, when tokenizing document text, the tokenizer |
12032 | ** provides multiple synonyms for each token. So that when a |
12033 | ** document such as "I won first place" is tokenized, entries are |
12034 | ** added to the FTS index for "i", "won", "first", "1st" and |
12035 | ** "place". |
12036 | ** |
12037 | ** This way, even if the tokenizer does not provide synonyms |
12038 | ** when tokenizing query text (it should not - to do so would be |
12039 | ** inefficient), it doesn't matter if the user queries for |
12040 | ** 'first + place' or '1st + place', as there are entries in the |
12041 | ** FTS index corresponding to both forms of the first token. |
12042 | ** </ol> |
12043 | ** |
12044 | ** Whether it is parsing document or query text, any call to xToken that |
12045 | ** specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit |
12046 | ** is considered to supply a synonym for the previous token. For example, |
12047 | ** when parsing the document "I won first place", a tokenizer that supports |
12048 | ** synonyms would call xToken() 5 times, as follows: |
12049 | ** |
12050 | ** <codeblock> |
12051 | ** xToken(pCtx, 0, "i", 1, 0, 1); |
12052 | ** xToken(pCtx, 0, "won", 3, 2, 5); |
12053 | ** xToken(pCtx, 0, "first", 5, 6, 11); |
12054 | ** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11); |
12055 | ** xToken(pCtx, 0, "place", 5, 12, 17); |
12056 | **</codeblock> |
12057 | ** |
12058 | ** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time |
12059 | ** xToken() is called. Multiple synonyms may be specified for a single token |
12060 | ** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence. |
12061 | ** There is no limit to the number of synonyms that may be provided for a |
12062 | ** single token. |
12063 | ** |
12064 | ** In many cases, method (1) above is the best approach. It does not add |
12065 | ** extra data to the FTS index or require FTS5 to query for multiple terms, |
12066 | ** so it is efficient in terms of disk space and query speed. However, it |
12067 | ** does not support prefix queries very well. If, as suggested above, the |
12068 | ** token "first" is substituted for "1st" by the tokenizer, then the query: |
12069 | ** |
12070 | ** <codeblock> |
12071 | ** ... MATCH '1s*'</codeblock> |
12072 | ** |
12073 | ** will not match documents that contain the token "1st" (as the tokenizer |
12074 | ** will probably not map "1s" to any prefix of "first"). |
12075 | ** |
12076 | ** For full prefix support, method (3) may be preferred. In this case, |
12077 | ** because the index contains entries for both "first" and "1st", prefix |
12078 | ** queries such as 'fi*' or '1s*' will match correctly. However, because |
12079 | ** extra entries are added to the FTS index, this method uses more space |
12080 | ** within the database. |
12081 | ** |
12082 | ** Method (2) offers a midpoint between (1) and (3). Using this method, |
12083 | ** a query such as '1s*' will match documents that contain the literal |
12084 | ** token "1st", but not "first" (assuming the tokenizer is not able to |
12085 | ** provide synonyms for prefixes). However, a non-prefix query like '1st' |
12086 | ** will match against "1st" and "first". This method does not require |
12087 | ** extra disk space, as no extra entries are added to the FTS index. |
12088 | ** On the other hand, it may require more CPU cycles to run MATCH queries, |
12089 | ** as separate queries of the FTS index are required for each synonym. |
12090 | ** |
12091 | ** When using methods (2) or (3), it is important that the tokenizer only |
12092 | ** provide synonyms when tokenizing document text (method (2)) or query |
12093 | ** text (method (3)), not both. Doing so will not cause any errors, but is |
12094 | ** inefficient. |
12095 | */ |
12096 | typedef struct Fts5Tokenizer Fts5Tokenizer; |
12097 | typedef struct fts5_tokenizer fts5_tokenizer; |
12098 | struct fts5_tokenizer { |
12099 | int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut); |
12100 | void (*xDelete)(Fts5Tokenizer*); |
12101 | int (*xTokenize)(Fts5Tokenizer*, |
12102 | void *pCtx, |
12103 | int flags, /* Mask of FTS5_TOKENIZE_* flags */ |
12104 | const char *pText, int nText, |
12105 | int (*xToken)( |
12106 | void *pCtx, /* Copy of 2nd argument to xTokenize() */ |
12107 | int tflags, /* Mask of FTS5_TOKEN_* flags */ |
12108 | const char *pToken, /* Pointer to buffer containing token */ |
12109 | int nToken, /* Size of token in bytes */ |
12110 | int iStart, /* Byte offset of token within input text */ |
12111 | int iEnd /* Byte offset of end of token within input text */ |
12112 | ) |
12113 | ); |
12114 | }; |
12115 | |
12116 | /* Flags that may be passed as the third argument to xTokenize() */ |
12117 | #define FTS5_TOKENIZE_QUERY 0x0001 |
12118 | #define FTS5_TOKENIZE_PREFIX 0x0002 |
12119 | #define FTS5_TOKENIZE_DOCUMENT 0x0004 |
12120 | #define FTS5_TOKENIZE_AUX 0x0008 |
12121 | |
12122 | /* Flags that may be passed by the tokenizer implementation back to FTS5 |
12123 | ** as the third argument to the supplied xToken callback. */ |
12124 | #define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */ |
12125 | |
12126 | /* |
12127 | ** END OF CUSTOM TOKENIZERS |
12128 | *************************************************************************/ |
12129 | |
12130 | /************************************************************************* |
12131 | ** FTS5 EXTENSION REGISTRATION API |
12132 | */ |
12133 | typedef struct fts5_api fts5_api; |
12134 | struct fts5_api { |
12135 | int iVersion; /* Currently always set to 2 */ |
12136 | |
12137 | /* Create a new tokenizer */ |
12138 | int (*xCreateTokenizer)( |
12139 | fts5_api *pApi, |
12140 | const char *zName, |
12141 | void *pContext, |
12142 | fts5_tokenizer *pTokenizer, |
12143 | void (*xDestroy)(void*) |
12144 | ); |
12145 | |
12146 | /* Find an existing tokenizer */ |
12147 | int (*xFindTokenizer)( |
12148 | fts5_api *pApi, |
12149 | const char *zName, |
12150 | void **ppContext, |
12151 | fts5_tokenizer *pTokenizer |
12152 | ); |
12153 | |
12154 | /* Create a new auxiliary function */ |
12155 | int (*xCreateFunction)( |
12156 | fts5_api *pApi, |
12157 | const char *zName, |
12158 | void *pContext, |
12159 | fts5_extension_function xFunction, |
12160 | void (*xDestroy)(void*) |
12161 | ); |
12162 | }; |
12163 | |
12164 | /* |
12165 | ** END OF REGISTRATION API |
12166 | *************************************************************************/ |
12167 | |
12168 | #ifdef __cplusplus |
12169 | } /* end of the 'extern "C"' block */ |
12170 | #endif |
12171 | |
12172 | #endif /* _FTS5_H */ |
12173 | |
12174 | /******** End of fts5.h *********/ |
12175 | |