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 "3.25.2" |
127 | #define SQLITE_VERSION_NUMBER 3025002 |
128 | #define SQLITE_SOURCE_ID "2018-09-25 19:08:10 fb90e7189ae6d62e77ba3a308ca5d683f90bbe633cf681865365b8e92792d1c7" |
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 | #endif |
193 | |
194 | /* |
195 | ** CAPI3REF: Test To See If The Library Is Threadsafe |
196 | ** |
197 | ** ^The sqlite3_threadsafe() function returns zero if and only if |
198 | ** SQLite was compiled with mutexing code omitted due to the |
199 | ** [SQLITE_THREADSAFE] compile-time option being set to 0. |
200 | ** |
201 | ** SQLite can be compiled with or without mutexes. When |
202 | ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes |
203 | ** are enabled and SQLite is threadsafe. When the |
204 | ** [SQLITE_THREADSAFE] macro is 0, |
205 | ** the mutexes are omitted. Without the mutexes, it is not safe |
206 | ** to use SQLite concurrently from more than one thread. |
207 | ** |
208 | ** Enabling mutexes incurs a measurable performance penalty. |
209 | ** So if speed is of utmost importance, it makes sense to disable |
210 | ** the mutexes. But for maximum safety, mutexes should be enabled. |
211 | ** ^The default behavior is for mutexes to be enabled. |
212 | ** |
213 | ** This interface can be used by an application to make sure that the |
214 | ** version of SQLite that it is linking against was compiled with |
215 | ** the desired setting of the [SQLITE_THREADSAFE] macro. |
216 | ** |
217 | ** This interface only reports on the compile-time mutex setting |
218 | ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with |
219 | ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but |
220 | ** can be fully or partially disabled using a call to [sqlite3_config()] |
221 | ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], |
222 | ** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the |
223 | ** sqlite3_threadsafe() function shows only the compile-time setting of |
224 | ** thread safety, not any run-time changes to that setting made by |
225 | ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe() |
226 | ** is unchanged by calls to sqlite3_config().)^ |
227 | ** |
228 | ** See the [threading mode] documentation for additional information. |
229 | */ |
230 | SQLITE_API int sqlite3_threadsafe(void); |
231 | |
232 | /* |
233 | ** CAPI3REF: Database Connection Handle |
234 | ** KEYWORDS: {database connection} {database connections} |
235 | ** |
236 | ** Each open SQLite database is represented by a pointer to an instance of |
237 | ** the opaque structure named "sqlite3". It is useful to think of an sqlite3 |
238 | ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and |
239 | ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] |
240 | ** and [sqlite3_close_v2()] are its destructors. There are many other |
241 | ** interfaces (such as |
242 | ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and |
243 | ** [sqlite3_busy_timeout()] to name but three) that are methods on an |
244 | ** sqlite3 object. |
245 | */ |
246 | typedef struct sqlite3 sqlite3; |
247 | |
248 | /* |
249 | ** CAPI3REF: 64-Bit Integer Types |
250 | ** KEYWORDS: sqlite_int64 sqlite_uint64 |
251 | ** |
252 | ** Because there is no cross-platform way to specify 64-bit integer types |
253 | ** SQLite includes typedefs for 64-bit signed and unsigned integers. |
254 | ** |
255 | ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. |
256 | ** The sqlite_int64 and sqlite_uint64 types are supported for backwards |
257 | ** compatibility only. |
258 | ** |
259 | ** ^The sqlite3_int64 and sqlite_int64 types can store integer values |
260 | ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The |
261 | ** sqlite3_uint64 and sqlite_uint64 types can store integer values |
262 | ** between 0 and +18446744073709551615 inclusive. |
263 | */ |
264 | #ifdef SQLITE_INT64_TYPE |
265 | typedef SQLITE_INT64_TYPE sqlite_int64; |
266 | # ifdef SQLITE_UINT64_TYPE |
267 | typedef SQLITE_UINT64_TYPE sqlite_uint64; |
268 | # else |
269 | typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; |
270 | # endif |
271 | #elif defined(_MSC_VER) || defined(__BORLANDC__) |
272 | typedef __int64 sqlite_int64; |
273 | typedef unsigned __int64 sqlite_uint64; |
274 | #else |
275 | typedef long long int sqlite_int64; |
276 | typedef unsigned long long int sqlite_uint64; |
277 | #endif |
278 | typedef sqlite_int64 sqlite3_int64; |
279 | typedef sqlite_uint64 sqlite3_uint64; |
280 | |
281 | /* |
282 | ** If compiling for a processor that lacks floating point support, |
283 | ** substitute integer for floating-point. |
284 | */ |
285 | #ifdef SQLITE_OMIT_FLOATING_POINT |
286 | # define double sqlite3_int64 |
287 | #endif |
288 | |
289 | /* |
290 | ** CAPI3REF: Closing A Database Connection |
291 | ** DESTRUCTOR: sqlite3 |
292 | ** |
293 | ** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors |
294 | ** for the [sqlite3] object. |
295 | ** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if |
296 | ** the [sqlite3] object is successfully destroyed and all associated |
297 | ** resources are deallocated. |
298 | ** |
299 | ** ^If the database connection is associated with unfinalized prepared |
300 | ** statements or unfinished sqlite3_backup objects then sqlite3_close() |
301 | ** will leave the database connection open and return [SQLITE_BUSY]. |
302 | ** ^If sqlite3_close_v2() is called with unfinalized prepared statements |
303 | ** and/or unfinished sqlite3_backups, then the database connection becomes |
304 | ** an unusable "zombie" which will automatically be deallocated when the |
305 | ** last prepared statement is finalized or the last sqlite3_backup is |
306 | ** finished. The sqlite3_close_v2() interface is intended for use with |
307 | ** host languages that are garbage collected, and where the order in which |
308 | ** destructors are called is arbitrary. |
309 | ** |
310 | ** Applications should [sqlite3_finalize | finalize] all [prepared statements], |
311 | ** [sqlite3_blob_close | close] all [BLOB handles], and |
312 | ** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated |
313 | ** with the [sqlite3] object prior to attempting to close the object. ^If |
314 | ** sqlite3_close_v2() is called on a [database connection] that still has |
315 | ** outstanding [prepared statements], [BLOB handles], and/or |
316 | ** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation |
317 | ** of resources is deferred until all [prepared statements], [BLOB handles], |
318 | ** and [sqlite3_backup] objects are also destroyed. |
319 | ** |
320 | ** ^If an [sqlite3] object is destroyed while a transaction is open, |
321 | ** the transaction is automatically rolled back. |
322 | ** |
323 | ** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)] |
324 | ** must be either a NULL |
325 | ** pointer or an [sqlite3] object pointer obtained |
326 | ** from [sqlite3_open()], [sqlite3_open16()], or |
327 | ** [sqlite3_open_v2()], and not previously closed. |
328 | ** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer |
329 | ** argument is a harmless no-op. |
330 | */ |
331 | SQLITE_API int sqlite3_close(sqlite3*); |
332 | SQLITE_API int sqlite3_close_v2(sqlite3*); |
333 | |
334 | /* |
335 | ** The type for a callback function. |
336 | ** This is legacy and deprecated. It is included for historical |
337 | ** compatibility and is not documented. |
338 | */ |
339 | typedef int (*sqlite3_callback)(void*,int,char**, char**); |
340 | |
341 | /* |
342 | ** CAPI3REF: One-Step Query Execution Interface |
343 | ** METHOD: sqlite3 |
344 | ** |
345 | ** The sqlite3_exec() interface is a convenience wrapper around |
346 | ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()], |
347 | ** that allows an application to run multiple statements of SQL |
348 | ** without having to use a lot of C code. |
349 | ** |
350 | ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded, |
351 | ** semicolon-separate SQL statements passed into its 2nd argument, |
352 | ** in the context of the [database connection] passed in as its 1st |
353 | ** argument. ^If the callback function of the 3rd argument to |
354 | ** sqlite3_exec() is not NULL, then it is invoked for each result row |
355 | ** coming out of the evaluated SQL statements. ^The 4th argument to |
356 | ** sqlite3_exec() is relayed through to the 1st argument of each |
357 | ** callback invocation. ^If the callback pointer to sqlite3_exec() |
358 | ** is NULL, then no callback is ever invoked and result rows are |
359 | ** ignored. |
360 | ** |
361 | ** ^If an error occurs while evaluating the SQL statements passed into |
362 | ** sqlite3_exec(), then execution of the current statement stops and |
363 | ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec() |
364 | ** is not NULL then any error message is written into memory obtained |
365 | ** from [sqlite3_malloc()] and passed back through the 5th parameter. |
366 | ** To avoid memory leaks, the application should invoke [sqlite3_free()] |
367 | ** on error message strings returned through the 5th parameter of |
368 | ** sqlite3_exec() after the error message string is no longer needed. |
369 | ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors |
370 | ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to |
371 | ** NULL before returning. |
372 | ** |
373 | ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec() |
374 | ** routine returns SQLITE_ABORT without invoking the callback again and |
375 | ** without running any subsequent SQL statements. |
376 | ** |
377 | ** ^The 2nd argument to the sqlite3_exec() callback function is the |
378 | ** number of columns in the result. ^The 3rd argument to the sqlite3_exec() |
379 | ** callback is an array of pointers to strings obtained as if from |
380 | ** [sqlite3_column_text()], one for each column. ^If an element of a |
381 | ** result row is NULL then the corresponding string pointer for the |
382 | ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the |
383 | ** sqlite3_exec() callback is an array of pointers to strings where each |
384 | ** entry represents the name of corresponding result column as obtained |
385 | ** from [sqlite3_column_name()]. |
386 | ** |
387 | ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer |
388 | ** to an empty string, or a pointer that contains only whitespace and/or |
389 | ** SQL comments, then no SQL statements are evaluated and the database |
390 | ** is not changed. |
391 | ** |
392 | ** Restrictions: |
393 | ** |
394 | ** <ul> |
395 | ** <li> The application must ensure that the 1st parameter to sqlite3_exec() |
396 | ** is a valid and open [database connection]. |
397 | ** <li> The application must not close the [database connection] specified by |
398 | ** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running. |
399 | ** <li> The application must not modify the SQL statement text passed into |
400 | ** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running. |
401 | ** </ul> |
402 | */ |
403 | SQLITE_API int sqlite3_exec( |
404 | sqlite3*, /* An open database */ |
405 | const char *sql, /* SQL to be evaluated */ |
406 | int (*callback)(void*,int,char**,char**), /* Callback function */ |
407 | void *, /* 1st argument to callback */ |
408 | char **errmsg /* Error msg written here */ |
409 | ); |
410 | |
411 | /* |
412 | ** CAPI3REF: Result Codes |
413 | ** KEYWORDS: {result code definitions} |
414 | ** |
415 | ** Many SQLite functions return an integer result code from the set shown |
416 | ** here in order to indicate success or failure. |
417 | ** |
418 | ** New error codes may be added in future versions of SQLite. |
419 | ** |
420 | ** See also: [extended result code definitions] |
421 | */ |
422 | #define SQLITE_OK 0 /* Successful result */ |
423 | /* beginning-of-error-codes */ |
424 | #define SQLITE_ERROR 1 /* Generic error */ |
425 | #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ |
426 | #define SQLITE_PERM 3 /* Access permission denied */ |
427 | #define SQLITE_ABORT 4 /* Callback routine requested an abort */ |
428 | #define SQLITE_BUSY 5 /* The database file is locked */ |
429 | #define SQLITE_LOCKED 6 /* A table in the database is locked */ |
430 | #define SQLITE_NOMEM 7 /* A malloc() failed */ |
431 | #define SQLITE_READONLY 8 /* Attempt to write a readonly database */ |
432 | #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ |
433 | #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ |
434 | #define SQLITE_CORRUPT 11 /* The database disk image is malformed */ |
435 | #define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */ |
436 | #define SQLITE_FULL 13 /* Insertion failed because database is full */ |
437 | #define SQLITE_CANTOPEN 14 /* Unable to open the database file */ |
438 | #define SQLITE_PROTOCOL 15 /* Database lock protocol error */ |
439 | #define SQLITE_EMPTY 16 /* Internal use only */ |
440 | #define SQLITE_SCHEMA 17 /* The database schema changed */ |
441 | #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ |
442 | #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ |
443 | #define SQLITE_MISMATCH 20 /* Data type mismatch */ |
444 | #define SQLITE_MISUSE 21 /* Library used incorrectly */ |
445 | #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ |
446 | #define SQLITE_AUTH 23 /* Authorization denied */ |
447 | #define SQLITE_FORMAT 24 /* Not used */ |
448 | #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ |
449 | #define SQLITE_NOTADB 26 /* File opened that is not a database file */ |
450 | #define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */ |
451 | #define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */ |
452 | #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ |
453 | #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ |
454 | /* end-of-error-codes */ |
455 | |
456 | /* |
457 | ** CAPI3REF: Extended Result Codes |
458 | ** KEYWORDS: {extended result code definitions} |
459 | ** |
460 | ** In its default configuration, SQLite API routines return one of 30 integer |
461 | ** [result codes]. However, experience has shown that many of |
462 | ** these result codes are too coarse-grained. They do not provide as |
463 | ** much information about problems as programmers might like. In an effort to |
464 | ** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8] |
465 | ** and later) include |
466 | ** support for additional result codes that provide more detailed information |
467 | ** about errors. These [extended result codes] are enabled or disabled |
468 | ** on a per database connection basis using the |
469 | ** [sqlite3_extended_result_codes()] API. Or, the extended code for |
470 | ** the most recent error can be obtained using |
471 | ** [sqlite3_extended_errcode()]. |
472 | */ |
473 | #define SQLITE_ERROR_MISSING_COLLSEQ (SQLITE_ERROR | (1<<8)) |
474 | #define SQLITE_ERROR_RETRY (SQLITE_ERROR | (2<<8)) |
475 | #define SQLITE_ERROR_SNAPSHOT (SQLITE_ERROR | (3<<8)) |
476 | #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) |
477 | #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) |
478 | #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) |
479 | #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) |
480 | #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) |
481 | #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) |
482 | #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) |
483 | #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) |
484 | #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) |
485 | #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) |
486 | #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) |
487 | #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) |
488 | #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) |
489 | #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) |
490 | #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) |
491 | #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8)) |
492 | #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8)) |
493 | #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8)) |
494 | #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8)) |
495 | #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8)) |
496 | #define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8)) |
497 | #define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8)) |
498 | #define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8)) |
499 | #define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8)) |
500 | #define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8)) |
501 | #define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8)) |
502 | #define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8)) |
503 | #define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8)) |
504 | #define SQLITE_IOERR_BEGIN_ATOMIC (SQLITE_IOERR | (29<<8)) |
505 | #define SQLITE_IOERR_COMMIT_ATOMIC (SQLITE_IOERR | (30<<8)) |
506 | #define SQLITE_IOERR_ROLLBACK_ATOMIC (SQLITE_IOERR | (31<<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_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8)) |
512 | #define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8)) |
513 | #define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8)) |
514 | #define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8)) |
515 | #define SQLITE_CANTOPEN_DIRTYWAL (SQLITE_CANTOPEN | (5<<8)) /* Not Used */ |
516 | #define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8)) |
517 | #define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8)) |
518 | #define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8)) |
519 | #define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8)) |
520 | #define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8)) |
521 | #define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8)) |
522 | #define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8)) |
523 | #define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8)) |
524 | #define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8)) |
525 | #define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8)) |
526 | #define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8)) |
527 | #define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8)) |
528 | #define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8)) |
529 | #define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8)) |
530 | #define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8)) |
531 | #define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8)) |
532 | #define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8)) |
533 | #define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8)) |
534 | #define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8)) |
535 | #define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8)) |
536 | #define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8)) |
537 | #define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8)) |
538 | #define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8)) |
539 | #define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8)) |
540 | |
541 | /* |
542 | ** CAPI3REF: Flags For File Open Operations |
543 | ** |
544 | ** These bit values are intended for use in the |
545 | ** 3rd parameter to the [sqlite3_open_v2()] interface and |
546 | ** in the 4th parameter to the [sqlite3_vfs.xOpen] method. |
547 | */ |
548 | #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ |
549 | #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ |
550 | #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ |
551 | #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ |
552 | #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ |
553 | #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */ |
554 | #define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */ |
555 | #define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */ |
556 | #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ |
557 | #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ |
558 | #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ |
559 | #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ |
560 | #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ |
561 | #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ |
562 | #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ |
563 | #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ |
564 | #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ |
565 | #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ |
566 | #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ |
567 | #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */ |
568 | |
569 | /* Reserved: 0x00F00000 */ |
570 | |
571 | /* |
572 | ** CAPI3REF: Device Characteristics |
573 | ** |
574 | ** The xDeviceCharacteristics method of the [sqlite3_io_methods] |
575 | ** object returns an integer which is a vector of these |
576 | ** bit values expressing I/O characteristics of the mass storage |
577 | ** device that holds the file that the [sqlite3_io_methods] |
578 | ** refers to. |
579 | ** |
580 | ** The SQLITE_IOCAP_ATOMIC property means that all writes of |
581 | ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values |
582 | ** mean that writes of blocks that are nnn bytes in size and |
583 | ** are aligned to an address which is an integer multiple of |
584 | ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means |
585 | ** that when data is appended to a file, the data is appended |
586 | ** first then the size of the file is extended, never the other |
587 | ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that |
588 | ** information is written to disk in the same order as calls |
589 | ** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that |
590 | ** after reboot following a crash or power loss, the only bytes in a |
591 | ** file that were written at the application level might have changed |
592 | ** and that adjacent bytes, even bytes within the same sector are |
593 | ** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN |
594 | ** flag indicates that a file cannot be deleted when open. The |
595 | ** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on |
596 | ** read-only media and cannot be changed even by processes with |
597 | ** elevated privileges. |
598 | ** |
599 | ** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying |
600 | ** filesystem supports doing multiple write operations atomically when those |
601 | ** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and |
602 | ** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. |
603 | */ |
604 | #define SQLITE_IOCAP_ATOMIC 0x00000001 |
605 | #define SQLITE_IOCAP_ATOMIC512 0x00000002 |
606 | #define SQLITE_IOCAP_ATOMIC1K 0x00000004 |
607 | #define SQLITE_IOCAP_ATOMIC2K 0x00000008 |
608 | #define SQLITE_IOCAP_ATOMIC4K 0x00000010 |
609 | #define SQLITE_IOCAP_ATOMIC8K 0x00000020 |
610 | #define SQLITE_IOCAP_ATOMIC16K 0x00000040 |
611 | #define SQLITE_IOCAP_ATOMIC32K 0x00000080 |
612 | #define SQLITE_IOCAP_ATOMIC64K 0x00000100 |
613 | #define SQLITE_IOCAP_SAFE_APPEND 0x00000200 |
614 | #define SQLITE_IOCAP_SEQUENTIAL 0x00000400 |
615 | #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800 |
616 | #define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000 |
617 | #define SQLITE_IOCAP_IMMUTABLE 0x00002000 |
618 | #define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000 |
619 | |
620 | /* |
621 | ** CAPI3REF: File Locking Levels |
622 | ** |
623 | ** SQLite uses one of these integer values as the second |
624 | ** argument to calls it makes to the xLock() and xUnlock() methods |
625 | ** of an [sqlite3_io_methods] object. |
626 | */ |
627 | #define SQLITE_LOCK_NONE 0 |
628 | #define SQLITE_LOCK_SHARED 1 |
629 | #define SQLITE_LOCK_RESERVED 2 |
630 | #define SQLITE_LOCK_PENDING 3 |
631 | #define SQLITE_LOCK_EXCLUSIVE 4 |
632 | |
633 | /* |
634 | ** CAPI3REF: Synchronization Type Flags |
635 | ** |
636 | ** When SQLite invokes the xSync() method of an |
637 | ** [sqlite3_io_methods] object it uses a combination of |
638 | ** these integer values as the second argument. |
639 | ** |
640 | ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the |
641 | ** sync operation only needs to flush data to mass storage. Inode |
642 | ** information need not be flushed. If the lower four bits of the flag |
643 | ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. |
644 | ** If the lower four bits equal SQLITE_SYNC_FULL, that means |
645 | ** to use Mac OS X style fullsync instead of fsync(). |
646 | ** |
647 | ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags |
648 | ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL |
649 | ** settings. The [synchronous pragma] determines when calls to the |
650 | ** xSync VFS method occur and applies uniformly across all platforms. |
651 | ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how |
652 | ** energetic or rigorous or forceful the sync operations are and |
653 | ** only make a difference on Mac OSX for the default SQLite code. |
654 | ** (Third-party VFS implementations might also make the distinction |
655 | ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the |
656 | ** operating systems natively supported by SQLite, only Mac OSX |
657 | ** cares about the difference.) |
658 | */ |
659 | #define SQLITE_SYNC_NORMAL 0x00002 |
660 | #define SQLITE_SYNC_FULL 0x00003 |
661 | #define SQLITE_SYNC_DATAONLY 0x00010 |
662 | |
663 | /* |
664 | ** CAPI3REF: OS Interface Open File Handle |
665 | ** |
666 | ** An [sqlite3_file] object represents an open file in the |
667 | ** [sqlite3_vfs | OS interface layer]. Individual OS interface |
668 | ** implementations will |
669 | ** want to subclass this object by appending additional fields |
670 | ** for their own use. The pMethods entry is a pointer to an |
671 | ** [sqlite3_io_methods] object that defines methods for performing |
672 | ** I/O operations on the open file. |
673 | */ |
674 | typedef struct sqlite3_file sqlite3_file; |
675 | struct sqlite3_file { |
676 | const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ |
677 | }; |
678 | |
679 | /* |
680 | ** CAPI3REF: OS Interface File Virtual Methods Object |
681 | ** |
682 | ** Every file opened by the [sqlite3_vfs.xOpen] method populates an |
683 | ** [sqlite3_file] object (or, more commonly, a subclass of the |
684 | ** [sqlite3_file] object) with a pointer to an instance of this object. |
685 | ** This object defines the methods used to perform various operations |
686 | ** against the open file represented by the [sqlite3_file] object. |
687 | ** |
688 | ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element |
689 | ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method |
690 | ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The |
691 | ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen] |
692 | ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element |
693 | ** to NULL. |
694 | ** |
695 | ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or |
696 | ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). |
697 | ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] |
698 | ** flag may be ORed in to indicate that only the data of the file |
699 | ** and not its inode needs to be synced. |
700 | ** |
701 | ** The integer values to xLock() and xUnlock() are one of |
702 | ** <ul> |
703 | ** <li> [SQLITE_LOCK_NONE], |
704 | ** <li> [SQLITE_LOCK_SHARED], |
705 | ** <li> [SQLITE_LOCK_RESERVED], |
706 | ** <li> [SQLITE_LOCK_PENDING], or |
707 | ** <li> [SQLITE_LOCK_EXCLUSIVE]. |
708 | ** </ul> |
709 | ** xLock() increases the lock. xUnlock() decreases the lock. |
710 | ** The xCheckReservedLock() method checks whether any database connection, |
711 | ** either in this process or in some other process, is holding a RESERVED, |
712 | ** PENDING, or EXCLUSIVE lock on the file. It returns true |
713 | ** if such a lock exists and false otherwise. |
714 | ** |
715 | ** The xFileControl() method is a generic interface that allows custom |
716 | ** VFS implementations to directly control an open file using the |
717 | ** [sqlite3_file_control()] interface. The second "op" argument is an |
718 | ** integer opcode. The third argument is a generic pointer intended to |
719 | ** point to a structure that may contain arguments or space in which to |
720 | ** write return values. Potential uses for xFileControl() might be |
721 | ** functions to enable blocking locks with timeouts, to change the |
722 | ** locking strategy (for example to use dot-file locks), to inquire |
723 | ** about the status of a lock, or to break stale locks. The SQLite |
724 | ** core reserves all opcodes less than 100 for its own use. |
725 | ** A [file control opcodes | list of opcodes] less than 100 is available. |
726 | ** Applications that define a custom xFileControl method should use opcodes |
727 | ** greater than 100 to avoid conflicts. VFS implementations should |
728 | ** return [SQLITE_NOTFOUND] for file control opcodes that they do not |
729 | ** recognize. |
730 | ** |
731 | ** The xSectorSize() method returns the sector size of the |
732 | ** device that underlies the file. The sector size is the |
733 | ** minimum write that can be performed without disturbing |
734 | ** other bytes in the file. The xDeviceCharacteristics() |
735 | ** method returns a bit vector describing behaviors of the |
736 | ** underlying device: |
737 | ** |
738 | ** <ul> |
739 | ** <li> [SQLITE_IOCAP_ATOMIC] |
740 | ** <li> [SQLITE_IOCAP_ATOMIC512] |
741 | ** <li> [SQLITE_IOCAP_ATOMIC1K] |
742 | ** <li> [SQLITE_IOCAP_ATOMIC2K] |
743 | ** <li> [SQLITE_IOCAP_ATOMIC4K] |
744 | ** <li> [SQLITE_IOCAP_ATOMIC8K] |
745 | ** <li> [SQLITE_IOCAP_ATOMIC16K] |
746 | ** <li> [SQLITE_IOCAP_ATOMIC32K] |
747 | ** <li> [SQLITE_IOCAP_ATOMIC64K] |
748 | ** <li> [SQLITE_IOCAP_SAFE_APPEND] |
749 | ** <li> [SQLITE_IOCAP_SEQUENTIAL] |
750 | ** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN] |
751 | ** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE] |
752 | ** <li> [SQLITE_IOCAP_IMMUTABLE] |
753 | ** <li> [SQLITE_IOCAP_BATCH_ATOMIC] |
754 | ** </ul> |
755 | ** |
756 | ** The SQLITE_IOCAP_ATOMIC property means that all writes of |
757 | ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values |
758 | ** mean that writes of blocks that are nnn bytes in size and |
759 | ** are aligned to an address which is an integer multiple of |
760 | ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means |
761 | ** that when data is appended to a file, the data is appended |
762 | ** first then the size of the file is extended, never the other |
763 | ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that |
764 | ** information is written to disk in the same order as calls |
765 | ** to xWrite(). |
766 | ** |
767 | ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill |
768 | ** in the unread portions of the buffer with zeros. A VFS that |
769 | ** fails to zero-fill short reads might seem to work. However, |
770 | ** failure to zero-fill short reads will eventually lead to |
771 | ** database corruption. |
772 | */ |
773 | typedef struct sqlite3_io_methods sqlite3_io_methods; |
774 | struct sqlite3_io_methods { |
775 | int iVersion; |
776 | int (*xClose)(sqlite3_file*); |
777 | int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); |
778 | int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); |
779 | int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); |
780 | int (*xSync)(sqlite3_file*, int flags); |
781 | int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); |
782 | int (*xLock)(sqlite3_file*, int); |
783 | int (*xUnlock)(sqlite3_file*, int); |
784 | int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); |
785 | int (*xFileControl)(sqlite3_file*, int op, void *pArg); |
786 | int (*xSectorSize)(sqlite3_file*); |
787 | int (*xDeviceCharacteristics)(sqlite3_file*); |
788 | /* Methods above are valid for version 1 */ |
789 | int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**); |
790 | int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); |
791 | void (*xShmBarrier)(sqlite3_file*); |
792 | int (*xShmUnmap)(sqlite3_file*, int deleteFlag); |
793 | /* Methods above are valid for version 2 */ |
794 | int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp); |
795 | int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p); |
796 | /* Methods above are valid for version 3 */ |
797 | /* Additional methods may be added in future releases */ |
798 | }; |
799 | |
800 | /* |
801 | ** CAPI3REF: Standard File Control Opcodes |
802 | ** KEYWORDS: {file control opcodes} {file control opcode} |
803 | ** |
804 | ** These integer constants are opcodes for the xFileControl method |
805 | ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] |
806 | ** interface. |
807 | ** |
808 | ** <ul> |
809 | ** <li>[[SQLITE_FCNTL_LOCKSTATE]] |
810 | ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This |
811 | ** opcode causes the xFileControl method to write the current state of |
812 | ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], |
813 | ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) |
814 | ** into an integer that the pArg argument points to. This capability |
815 | ** is used during testing and is only available when the SQLITE_TEST |
816 | ** compile-time option is used. |
817 | ** |
818 | ** <li>[[SQLITE_FCNTL_SIZE_HINT]] |
819 | ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS |
820 | ** layer a hint of how large the database file will grow to be during the |
821 | ** current transaction. This hint is not guaranteed to be accurate but it |
822 | ** is often close. The underlying VFS might choose to preallocate database |
823 | ** file space based on this hint in order to help writes to the database |
824 | ** file run faster. |
825 | ** |
826 | ** <li>[[SQLITE_FCNTL_CHUNK_SIZE]] |
827 | ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS |
828 | ** extends and truncates the database file in chunks of a size specified |
829 | ** by the user. The fourth argument to [sqlite3_file_control()] should |
830 | ** point to an integer (type int) containing the new chunk-size to use |
831 | ** for the nominated database. Allocating database file space in large |
832 | ** chunks (say 1MB at a time), may reduce file-system fragmentation and |
833 | ** improve performance on some systems. |
834 | ** |
835 | ** <li>[[SQLITE_FCNTL_FILE_POINTER]] |
836 | ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer |
837 | ** to the [sqlite3_file] object associated with a particular database |
838 | ** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER]. |
839 | ** |
840 | ** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]] |
841 | ** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer |
842 | ** to the [sqlite3_file] object associated with the journal file (either |
843 | ** the [rollback journal] or the [write-ahead log]) for a particular database |
844 | ** connection. See also [SQLITE_FCNTL_FILE_POINTER]. |
845 | ** |
846 | ** <li>[[SQLITE_FCNTL_SYNC_OMITTED]] |
847 | ** No longer in use. |
848 | ** |
849 | ** <li>[[SQLITE_FCNTL_SYNC]] |
850 | ** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and |
851 | ** sent to the VFS immediately before the xSync method is invoked on a |
852 | ** database file descriptor. Or, if the xSync method is not invoked |
853 | ** because the user has configured SQLite with |
854 | ** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place |
855 | ** of the xSync method. In most cases, the pointer argument passed with |
856 | ** this file-control is NULL. However, if the database file is being synced |
857 | ** as part of a multi-database commit, the argument points to a nul-terminated |
858 | ** string containing the transactions master-journal file name. VFSes that |
859 | ** do not need this signal should silently ignore this opcode. Applications |
860 | ** should not call [sqlite3_file_control()] with this opcode as doing so may |
861 | ** disrupt the operation of the specialized VFSes that do require it. |
862 | ** |
863 | ** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]] |
864 | ** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite |
865 | ** and sent to the VFS after a transaction has been committed immediately |
866 | ** but before the database is unlocked. VFSes that do not need this signal |
867 | ** should silently ignore this opcode. Applications should not call |
868 | ** [sqlite3_file_control()] with this opcode as doing so may disrupt the |
869 | ** operation of the specialized VFSes that do require it. |
870 | ** |
871 | ** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]] |
872 | ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic |
873 | ** retry counts and intervals for certain disk I/O operations for the |
874 | ** windows [VFS] in order to provide robustness in the presence of |
875 | ** anti-virus programs. By default, the windows VFS will retry file read, |
876 | ** file write, and file delete operations up to 10 times, with a delay |
877 | ** of 25 milliseconds before the first retry and with the delay increasing |
878 | ** by an additional 25 milliseconds with each subsequent retry. This |
879 | ** opcode allows these two values (10 retries and 25 milliseconds of delay) |
880 | ** to be adjusted. The values are changed for all database connections |
881 | ** within the same process. The argument is a pointer to an array of two |
882 | ** integers where the first integer is the new retry count and the second |
883 | ** integer is the delay. If either integer is negative, then the setting |
884 | ** is not changed but instead the prior value of that setting is written |
885 | ** into the array entry, allowing the current retry settings to be |
886 | ** interrogated. The zDbName parameter is ignored. |
887 | ** |
888 | ** <li>[[SQLITE_FCNTL_PERSIST_WAL]] |
889 | ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the |
890 | ** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary |
891 | ** write ahead log ([WAL file]) and shared memory |
892 | ** files used for transaction control |
893 | ** are automatically deleted when the latest connection to the database |
894 | ** closes. Setting persistent WAL mode causes those files to persist after |
895 | ** close. Persisting the files is useful when other processes that do not |
896 | ** have write permission on the directory containing the database file want |
897 | ** to read the database file, as the WAL and shared memory files must exist |
898 | ** in order for the database to be readable. The fourth parameter to |
899 | ** [sqlite3_file_control()] for this opcode should be a pointer to an integer. |
900 | ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent |
901 | ** WAL mode. If the integer is -1, then it is overwritten with the current |
902 | ** WAL persistence setting. |
903 | ** |
904 | ** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]] |
905 | ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the |
906 | ** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting |
907 | ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the |
908 | ** xDeviceCharacteristics methods. The fourth parameter to |
909 | ** [sqlite3_file_control()] for this opcode should be a pointer to an integer. |
910 | ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage |
911 | ** mode. If the integer is -1, then it is overwritten with the current |
912 | ** zero-damage mode setting. |
913 | ** |
914 | ** <li>[[SQLITE_FCNTL_OVERWRITE]] |
915 | ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening |
916 | ** a write transaction to indicate that, unless it is rolled back for some |
917 | ** reason, the entire database file will be overwritten by the current |
918 | ** transaction. This is used by VACUUM operations. |
919 | ** |
920 | ** <li>[[SQLITE_FCNTL_VFSNAME]] |
921 | ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of |
922 | ** all [VFSes] in the VFS stack. The names are of all VFS shims and the |
923 | ** final bottom-level VFS are written into memory obtained from |
924 | ** [sqlite3_malloc()] and the result is stored in the char* variable |
925 | ** that the fourth parameter of [sqlite3_file_control()] points to. |
926 | ** The caller is responsible for freeing the memory when done. As with |
927 | ** all file-control actions, there is no guarantee that this will actually |
928 | ** do anything. Callers should initialize the char* variable to a NULL |
929 | ** pointer in case this file-control is not implemented. This file-control |
930 | ** is intended for diagnostic use only. |
931 | ** |
932 | ** <li>[[SQLITE_FCNTL_VFS_POINTER]] |
933 | ** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level |
934 | ** [VFSes] currently in use. ^(The argument X in |
935 | ** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be |
936 | ** of type "[sqlite3_vfs] **". This opcodes will set *X |
937 | ** to a pointer to the top-level VFS.)^ |
938 | ** ^When there are multiple VFS shims in the stack, this opcode finds the |
939 | ** upper-most shim only. |
940 | ** |
941 | ** <li>[[SQLITE_FCNTL_PRAGMA]] |
942 | ** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] |
943 | ** file control is sent to the open [sqlite3_file] object corresponding |
944 | ** to the database file to which the pragma statement refers. ^The argument |
945 | ** to the [SQLITE_FCNTL_PRAGMA] file control is an array of |
946 | ** pointers to strings (char**) in which the second element of the array |
947 | ** is the name of the pragma and the third element is the argument to the |
948 | ** pragma or NULL if the pragma has no argument. ^The handler for an |
949 | ** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element |
950 | ** of the char** argument point to a string obtained from [sqlite3_mprintf()] |
951 | ** or the equivalent and that string will become the result of the pragma or |
952 | ** the error message if the pragma fails. ^If the |
953 | ** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal |
954 | ** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA] |
955 | ** file control returns [SQLITE_OK], then the parser assumes that the |
956 | ** VFS has handled the PRAGMA itself and the parser generates a no-op |
957 | ** prepared statement if result string is NULL, or that returns a copy |
958 | ** of the result string if the string is non-NULL. |
959 | ** ^If the [SQLITE_FCNTL_PRAGMA] file control returns |
960 | ** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means |
961 | ** that the VFS encountered an error while handling the [PRAGMA] and the |
962 | ** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA] |
963 | ** file control occurs at the beginning of pragma statement analysis and so |
964 | ** it is able to override built-in [PRAGMA] statements. |
965 | ** |
966 | ** <li>[[SQLITE_FCNTL_BUSYHANDLER]] |
967 | ** ^The [SQLITE_FCNTL_BUSYHANDLER] |
968 | ** file-control may be invoked by SQLite on the database file handle |
969 | ** shortly after it is opened in order to provide a custom VFS with access |
970 | ** to the connections busy-handler callback. The argument is of type (void **) |
971 | ** - an array of two (void *) values. The first (void *) actually points |
972 | ** to a function of type (int (*)(void *)). In order to invoke the connections |
973 | ** busy-handler, this function should be invoked with the second (void *) in |
974 | ** the array as the only argument. If it returns non-zero, then the operation |
975 | ** should be retried. If it returns zero, the custom VFS should abandon the |
976 | ** current operation. |
977 | ** |
978 | ** <li>[[SQLITE_FCNTL_TEMPFILENAME]] |
979 | ** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control |
980 | ** to have SQLite generate a |
981 | ** temporary filename using the same algorithm that is followed to generate |
982 | ** temporary filenames for TEMP tables and other internal uses. The |
983 | ** argument should be a char** which will be filled with the filename |
984 | ** written into memory obtained from [sqlite3_malloc()]. The caller should |
985 | ** invoke [sqlite3_free()] on the result to avoid a memory leak. |
986 | ** |
987 | ** <li>[[SQLITE_FCNTL_MMAP_SIZE]] |
988 | ** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the |
989 | ** maximum number of bytes that will be used for memory-mapped I/O. |
990 | ** The argument is a pointer to a value of type sqlite3_int64 that |
991 | ** is an advisory maximum number of bytes in the file to memory map. The |
992 | ** pointer is overwritten with the old value. The limit is not changed if |
993 | ** the value originally pointed to is negative, and so the current limit |
994 | ** can be queried by passing in a pointer to a negative number. This |
995 | ** file-control is used internally to implement [PRAGMA mmap_size]. |
996 | ** |
997 | ** <li>[[SQLITE_FCNTL_TRACE]] |
998 | ** The [SQLITE_FCNTL_TRACE] file control provides advisory information |
999 | ** to the VFS about what the higher layers of the SQLite stack are doing. |
1000 | ** This file control is used by some VFS activity tracing [shims]. |
1001 | ** The argument is a zero-terminated string. Higher layers in the |
1002 | ** SQLite stack may generate instances of this file control if |
1003 | ** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled. |
1004 | ** |
1005 | ** <li>[[SQLITE_FCNTL_HAS_MOVED]] |
1006 | ** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a |
1007 | ** pointer to an integer and it writes a boolean into that integer depending |
1008 | ** on whether or not the file has been renamed, moved, or deleted since it |
1009 | ** was first opened. |
1010 | ** |
1011 | ** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]] |
1012 | ** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the |
1013 | ** underlying native file handle associated with a file handle. This file |
1014 | ** control interprets its argument as a pointer to a native file handle and |
1015 | ** writes the resulting value there. |
1016 | ** |
1017 | ** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]] |
1018 | ** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This |
1019 | ** opcode causes the xFileControl method to swap the file handle with the one |
1020 | ** pointed to by the pArg argument. This capability is used during testing |
1021 | ** and only needs to be supported when SQLITE_TEST is defined. |
1022 | ** |
1023 | ** <li>[[SQLITE_FCNTL_WAL_BLOCK]] |
1024 | ** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might |
1025 | ** be advantageous to block on the next WAL lock if the lock is not immediately |
1026 | ** available. The WAL subsystem issues this signal during rare |
1027 | ** circumstances in order to fix a problem with priority inversion. |
1028 | ** Applications should <em>not</em> use this file-control. |
1029 | ** |
1030 | ** <li>[[SQLITE_FCNTL_ZIPVFS]] |
1031 | ** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other |
1032 | ** VFS should return SQLITE_NOTFOUND for this opcode. |
1033 | ** |
1034 | ** <li>[[SQLITE_FCNTL_RBU]] |
1035 | ** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by |
1036 | ** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for |
1037 | ** this opcode. |
1038 | ** |
1039 | ** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]] |
1040 | ** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then |
1041 | ** the file descriptor is placed in "batch write mode", which |
1042 | ** means all subsequent write operations will be deferred and done |
1043 | ** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. Systems |
1044 | ** that do not support batch atomic writes will return SQLITE_NOTFOUND. |
1045 | ** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to |
1046 | ** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or |
1047 | ** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make |
1048 | ** no VFS interface calls on the same [sqlite3_file] file descriptor |
1049 | ** except for calls to the xWrite method and the xFileControl method |
1050 | ** with [SQLITE_FCNTL_SIZE_HINT]. |
1051 | ** |
1052 | ** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]] |
1053 | ** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write |
1054 | ** operations since the previous successful call to |
1055 | ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically. |
1056 | ** This file control returns [SQLITE_OK] if and only if the writes were |
1057 | ** all performed successfully and have been committed to persistent storage. |
1058 | ** ^Regardless of whether or not it is successful, this file control takes |
1059 | ** the file descriptor out of batch write mode so that all subsequent |
1060 | ** write operations are independent. |
1061 | ** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without |
1062 | ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. |
1063 | ** |
1064 | ** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]] |
1065 | ** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write |
1066 | ** operations since the previous successful call to |
1067 | ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back. |
1068 | ** ^This file control takes the file descriptor out of batch write mode |
1069 | ** so that all subsequent write operations are independent. |
1070 | ** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without |
1071 | ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. |
1072 | ** |
1073 | ** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]] |
1074 | ** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode causes attempts to obtain |
1075 | ** a file lock using the xLock or xShmLock methods of the VFS to wait |
1076 | ** for up to M milliseconds before failing, where M is the single |
1077 | ** unsigned integer parameter. |
1078 | ** |
1079 | ** <li>[[SQLITE_FCNTL_DATA_VERSION]] |
1080 | ** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to |
1081 | ** a database file. The argument is a pointer to a 32-bit unsigned integer. |
1082 | ** The "data version" for the pager is written into the pointer. The |
1083 | ** "data version" changes whenever any change occurs to the corresponding |
1084 | ** database file, either through SQL statements on the same database |
1085 | ** connection or through transactions committed by separate database |
1086 | ** connections possibly in other processes. The [sqlite3_total_changes()] |
1087 | ** interface can be used to find if any database on the connection has changed, |
1088 | ** but that interface responds to changes on TEMP as well as MAIN and does |
1089 | ** not provide a mechanism to detect changes to MAIN only. Also, the |
1090 | ** [sqlite3_total_changes()] interface responds to internal changes only and |
1091 | ** omits changes made by other database connections. The |
1092 | ** [PRAGMA data_version] command provide a mechanism to detect changes to |
1093 | ** a single attached database that occur due to other database connections, |
1094 | ** but omits changes implemented by the database connection on which it is |
1095 | ** called. This file control is the only mechanism to detect changes that |
1096 | ** happen either internally or externally and that are associated with |
1097 | ** a particular attached database. |
1098 | ** </ul> |
1099 | */ |
1100 | #define SQLITE_FCNTL_LOCKSTATE 1 |
1101 | #define SQLITE_FCNTL_GET_LOCKPROXYFILE 2 |
1102 | #define SQLITE_FCNTL_SET_LOCKPROXYFILE 3 |
1103 | #define SQLITE_FCNTL_LAST_ERRNO 4 |
1104 | #define SQLITE_FCNTL_SIZE_HINT 5 |
1105 | #define SQLITE_FCNTL_CHUNK_SIZE 6 |
1106 | #define SQLITE_FCNTL_FILE_POINTER 7 |
1107 | #define SQLITE_FCNTL_SYNC_OMITTED 8 |
1108 | #define SQLITE_FCNTL_WIN32_AV_RETRY 9 |
1109 | #define SQLITE_FCNTL_PERSIST_WAL 10 |
1110 | #define SQLITE_FCNTL_OVERWRITE 11 |
1111 | #define SQLITE_FCNTL_VFSNAME 12 |
1112 | #define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13 |
1113 | #define SQLITE_FCNTL_PRAGMA 14 |
1114 | #define SQLITE_FCNTL_BUSYHANDLER 15 |
1115 | #define SQLITE_FCNTL_TEMPFILENAME 16 |
1116 | #define SQLITE_FCNTL_MMAP_SIZE 18 |
1117 | #define SQLITE_FCNTL_TRACE 19 |
1118 | #define SQLITE_FCNTL_HAS_MOVED 20 |
1119 | #define SQLITE_FCNTL_SYNC 21 |
1120 | #define SQLITE_FCNTL_COMMIT_PHASETWO 22 |
1121 | #define SQLITE_FCNTL_WIN32_SET_HANDLE 23 |
1122 | #define SQLITE_FCNTL_WAL_BLOCK 24 |
1123 | #define SQLITE_FCNTL_ZIPVFS 25 |
1124 | #define SQLITE_FCNTL_RBU 26 |
1125 | #define SQLITE_FCNTL_VFS_POINTER 27 |
1126 | #define SQLITE_FCNTL_JOURNAL_POINTER 28 |
1127 | #define SQLITE_FCNTL_WIN32_GET_HANDLE 29 |
1128 | #define SQLITE_FCNTL_PDB 30 |
1129 | #define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31 |
1130 | #define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32 |
1131 | #define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33 |
1132 | #define SQLITE_FCNTL_LOCK_TIMEOUT 34 |
1133 | #define SQLITE_FCNTL_DATA_VERSION 35 |
1134 | |
1135 | /* deprecated names */ |
1136 | #define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE |
1137 | #define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE |
1138 | #define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO |
1139 | |
1140 | |
1141 | /* |
1142 | ** CAPI3REF: Mutex Handle |
1143 | ** |
1144 | ** The mutex module within SQLite defines [sqlite3_mutex] to be an |
1145 | ** abstract type for a mutex object. The SQLite core never looks |
1146 | ** at the internal representation of an [sqlite3_mutex]. It only |
1147 | ** deals with pointers to the [sqlite3_mutex] object. |
1148 | ** |
1149 | ** Mutexes are created using [sqlite3_mutex_alloc()]. |
1150 | */ |
1151 | typedef struct sqlite3_mutex sqlite3_mutex; |
1152 | |
1153 | /* |
1154 | ** CAPI3REF: Loadable Extension Thunk |
1155 | ** |
1156 | ** A pointer to the opaque sqlite3_api_routines structure is passed as |
1157 | ** the third parameter to entry points of [loadable extensions]. This |
1158 | ** structure must be typedefed in order to work around compiler warnings |
1159 | ** on some platforms. |
1160 | */ |
1161 | typedef struct sqlite3_api_routines sqlite3_api_routines; |
1162 | |
1163 | /* |
1164 | ** CAPI3REF: OS Interface Object |
1165 | ** |
1166 | ** An instance of the sqlite3_vfs object defines the interface between |
1167 | ** the SQLite core and the underlying operating system. The "vfs" |
1168 | ** in the name of the object stands for "virtual file system". See |
1169 | ** the [VFS | VFS documentation] for further information. |
1170 | ** |
1171 | ** The VFS interface is sometimes extended by adding new methods onto |
1172 | ** the end. Each time such an extension occurs, the iVersion field |
1173 | ** is incremented. The iVersion value started out as 1 in |
1174 | ** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2 |
1175 | ** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased |
1176 | ** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields |
1177 | ** may be appended to the sqlite3_vfs object and the iVersion value |
1178 | ** may increase again in future versions of SQLite. |
1179 | ** Note that the structure |
1180 | ** of the sqlite3_vfs object changes in the transition from |
1181 | ** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0] |
1182 | ** and yet the iVersion field was not modified. |
1183 | ** |
1184 | ** The szOsFile field is the size of the subclassed [sqlite3_file] |
1185 | ** structure used by this VFS. mxPathname is the maximum length of |
1186 | ** a pathname in this VFS. |
1187 | ** |
1188 | ** Registered sqlite3_vfs objects are kept on a linked list formed by |
1189 | ** the pNext pointer. The [sqlite3_vfs_register()] |
1190 | ** and [sqlite3_vfs_unregister()] interfaces manage this list |
1191 | ** in a thread-safe way. The [sqlite3_vfs_find()] interface |
1192 | ** searches the list. Neither the application code nor the VFS |
1193 | ** implementation should use the pNext pointer. |
1194 | ** |
1195 | ** The pNext field is the only field in the sqlite3_vfs |
1196 | ** structure that SQLite will ever modify. SQLite will only access |
1197 | ** or modify this field while holding a particular static mutex. |
1198 | ** The application should never modify anything within the sqlite3_vfs |
1199 | ** object once the object has been registered. |
1200 | ** |
1201 | ** The zName field holds the name of the VFS module. The name must |
1202 | ** be unique across all VFS modules. |
1203 | ** |
1204 | ** [[sqlite3_vfs.xOpen]] |
1205 | ** ^SQLite guarantees that the zFilename parameter to xOpen |
1206 | ** is either a NULL pointer or string obtained |
1207 | ** from xFullPathname() with an optional suffix added. |
1208 | ** ^If a suffix is added to the zFilename parameter, it will |
1209 | ** consist of a single "-" character followed by no more than |
1210 | ** 11 alphanumeric and/or "-" characters. |
1211 | ** ^SQLite further guarantees that |
1212 | ** the string will be valid and unchanged until xClose() is |
1213 | ** called. Because of the previous sentence, |
1214 | ** the [sqlite3_file] can safely store a pointer to the |
1215 | ** filename if it needs to remember the filename for some reason. |
1216 | ** If the zFilename parameter to xOpen is a NULL pointer then xOpen |
1217 | ** must invent its own temporary name for the file. ^Whenever the |
1218 | ** xFilename parameter is NULL it will also be the case that the |
1219 | ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. |
1220 | ** |
1221 | ** The flags argument to xOpen() includes all bits set in |
1222 | ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] |
1223 | ** or [sqlite3_open16()] is used, then flags includes at least |
1224 | ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. |
1225 | ** If xOpen() opens a file read-only then it sets *pOutFlags to |
1226 | ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. |
1227 | ** |
1228 | ** ^(SQLite will also add one of the following flags to the xOpen() |
1229 | ** call, depending on the object being opened: |
1230 | ** |
1231 | ** <ul> |
1232 | ** <li> [SQLITE_OPEN_MAIN_DB] |
1233 | ** <li> [SQLITE_OPEN_MAIN_JOURNAL] |
1234 | ** <li> [SQLITE_OPEN_TEMP_DB] |
1235 | ** <li> [SQLITE_OPEN_TEMP_JOURNAL] |
1236 | ** <li> [SQLITE_OPEN_TRANSIENT_DB] |
1237 | ** <li> [SQLITE_OPEN_SUBJOURNAL] |
1238 | ** <li> [SQLITE_OPEN_MASTER_JOURNAL] |
1239 | ** <li> [SQLITE_OPEN_WAL] |
1240 | ** </ul>)^ |
1241 | ** |
1242 | ** The file I/O implementation can use the object type flags to |
1243 | ** change the way it deals with files. For example, an application |
1244 | ** that does not care about crash recovery or rollback might make |
1245 | ** the open of a journal file a no-op. Writes to this journal would |
1246 | ** also be no-ops, and any attempt to read the journal would return |
1247 | ** SQLITE_IOERR. Or the implementation might recognize that a database |
1248 | ** file will be doing page-aligned sector reads and writes in a random |
1249 | ** order and set up its I/O subsystem accordingly. |
1250 | ** |
1251 | ** SQLite might also add one of the following flags to the xOpen method: |
1252 | ** |
1253 | ** <ul> |
1254 | ** <li> [SQLITE_OPEN_DELETEONCLOSE] |
1255 | ** <li> [SQLITE_OPEN_EXCLUSIVE] |
1256 | ** </ul> |
1257 | ** |
1258 | ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be |
1259 | ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] |
1260 | ** will be set for TEMP databases and their journals, transient |
1261 | ** databases, and subjournals. |
1262 | ** |
1263 | ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction |
1264 | ** with the [SQLITE_OPEN_CREATE] flag, which are both directly |
1265 | ** analogous to the O_EXCL and O_CREAT flags of the POSIX open() |
1266 | ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the |
1267 | ** SQLITE_OPEN_CREATE, is used to indicate that file should always |
1268 | ** be created, and that it is an error if it already exists. |
1269 | ** It is <i>not</i> used to indicate the file should be opened |
1270 | ** for exclusive access. |
1271 | ** |
1272 | ** ^At least szOsFile bytes of memory are allocated by SQLite |
1273 | ** to hold the [sqlite3_file] structure passed as the third |
1274 | ** argument to xOpen. The xOpen method does not have to |
1275 | ** allocate the structure; it should just fill it in. Note that |
1276 | ** the xOpen method must set the sqlite3_file.pMethods to either |
1277 | ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do |
1278 | ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods |
1279 | ** element will be valid after xOpen returns regardless of the success |
1280 | ** or failure of the xOpen call. |
1281 | ** |
1282 | ** [[sqlite3_vfs.xAccess]] |
1283 | ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] |
1284 | ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to |
1285 | ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] |
1286 | ** to test whether a file is at least readable. The file can be a |
1287 | ** directory. |
1288 | ** |
1289 | ** ^SQLite will always allocate at least mxPathname+1 bytes for the |
1290 | ** output buffer xFullPathname. The exact size of the output buffer |
1291 | ** is also passed as a parameter to both methods. If the output buffer |
1292 | ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is |
1293 | ** handled as a fatal error by SQLite, vfs implementations should endeavor |
1294 | ** to prevent this by setting mxPathname to a sufficiently large value. |
1295 | ** |
1296 | ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() |
1297 | ** interfaces are not strictly a part of the filesystem, but they are |
1298 | ** included in the VFS structure for completeness. |
1299 | ** The xRandomness() function attempts to return nBytes bytes |
1300 | ** of good-quality randomness into zOut. The return value is |
1301 | ** the actual number of bytes of randomness obtained. |
1302 | ** The xSleep() method causes the calling thread to sleep for at |
1303 | ** least the number of microseconds given. ^The xCurrentTime() |
1304 | ** method returns a Julian Day Number for the current date and time as |
1305 | ** a floating point value. |
1306 | ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian |
1307 | ** Day Number multiplied by 86400000 (the number of milliseconds in |
1308 | ** a 24-hour day). |
1309 | ** ^SQLite will use the xCurrentTimeInt64() method to get the current |
1310 | ** date and time if that method is available (if iVersion is 2 or |
1311 | ** greater and the function pointer is not NULL) and will fall back |
1312 | ** to xCurrentTime() if xCurrentTimeInt64() is unavailable. |
1313 | ** |
1314 | ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces |
1315 | ** are not used by the SQLite core. These optional interfaces are provided |
1316 | ** by some VFSes to facilitate testing of the VFS code. By overriding |
1317 | ** system calls with functions under its control, a test program can |
1318 | ** simulate faults and error conditions that would otherwise be difficult |
1319 | ** or impossible to induce. The set of system calls that can be overridden |
1320 | ** varies from one VFS to another, and from one version of the same VFS to the |
1321 | ** next. Applications that use these interfaces must be prepared for any |
1322 | ** or all of these interfaces to be NULL or for their behavior to change |
1323 | ** from one release to the next. Applications must not attempt to access |
1324 | ** any of these methods if the iVersion of the VFS is less than 3. |
1325 | */ |
1326 | typedef struct sqlite3_vfs sqlite3_vfs; |
1327 | typedef void (*sqlite3_syscall_ptr)(void); |
1328 | struct sqlite3_vfs { |
1329 | int iVersion; /* Structure version number (currently 3) */ |
1330 | int szOsFile; /* Size of subclassed sqlite3_file */ |
1331 | int mxPathname; /* Maximum file pathname length */ |
1332 | sqlite3_vfs *pNext; /* Next registered VFS */ |
1333 | const char *zName; /* Name of this virtual file system */ |
1334 | void *pAppData; /* Pointer to application-specific data */ |
1335 | int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*, |
1336 | int flags, int *pOutFlags); |
1337 | int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); |
1338 | int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); |
1339 | int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); |
1340 | void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); |
1341 | void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); |
1342 | void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); |
1343 | void (*xDlClose)(sqlite3_vfs*, void*); |
1344 | int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); |
1345 | int (*xSleep)(sqlite3_vfs*, int microseconds); |
1346 | int (*xCurrentTime)(sqlite3_vfs*, double*); |
1347 | int (*xGetLastError)(sqlite3_vfs*, int, char *); |
1348 | /* |
1349 | ** The methods above are in version 1 of the sqlite_vfs object |
1350 | ** definition. Those that follow are added in version 2 or later |
1351 | */ |
1352 | int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*); |
1353 | /* |
1354 | ** The methods above are in versions 1 and 2 of the sqlite_vfs object. |
1355 | ** Those below are for version 3 and greater. |
1356 | */ |
1357 | int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr); |
1358 | sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName); |
1359 | const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName); |
1360 | /* |
1361 | ** The methods above are in versions 1 through 3 of the sqlite_vfs object. |
1362 | ** New fields may be appended in future versions. The iVersion |
1363 | ** value will increment whenever this happens. |
1364 | */ |
1365 | }; |
1366 | |
1367 | /* |
1368 | ** CAPI3REF: Flags for the xAccess VFS method |
1369 | ** |
1370 | ** These integer constants can be used as the third parameter to |
1371 | ** the xAccess method of an [sqlite3_vfs] object. They determine |
1372 | ** what kind of permissions the xAccess method is looking for. |
1373 | ** With SQLITE_ACCESS_EXISTS, the xAccess method |
1374 | ** simply checks whether the file exists. |
1375 | ** With SQLITE_ACCESS_READWRITE, the xAccess method |
1376 | ** checks whether the named directory is both readable and writable |
1377 | ** (in other words, if files can be added, removed, and renamed within |
1378 | ** the directory). |
1379 | ** The SQLITE_ACCESS_READWRITE constant is currently used only by the |
1380 | ** [temp_store_directory pragma], though this could change in a future |
1381 | ** release of SQLite. |
1382 | ** With SQLITE_ACCESS_READ, the xAccess method |
1383 | ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is |
1384 | ** currently unused, though it might be used in a future release of |
1385 | ** SQLite. |
1386 | */ |
1387 | #define SQLITE_ACCESS_EXISTS 0 |
1388 | #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */ |
1389 | #define SQLITE_ACCESS_READ 2 /* Unused */ |
1390 | |
1391 | /* |
1392 | ** CAPI3REF: Flags for the xShmLock VFS method |
1393 | ** |
1394 | ** These integer constants define the various locking operations |
1395 | ** allowed by the xShmLock method of [sqlite3_io_methods]. The |
1396 | ** following are the only legal combinations of flags to the |
1397 | ** xShmLock method: |
1398 | ** |
1399 | ** <ul> |
1400 | ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED |
1401 | ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE |
1402 | ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED |
1403 | ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE |
1404 | ** </ul> |
1405 | ** |
1406 | ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as |
1407 | ** was given on the corresponding lock. |
1408 | ** |
1409 | ** The xShmLock method can transition between unlocked and SHARED or |
1410 | ** between unlocked and EXCLUSIVE. It cannot transition between SHARED |
1411 | ** and EXCLUSIVE. |
1412 | */ |
1413 | #define SQLITE_SHM_UNLOCK 1 |
1414 | #define SQLITE_SHM_LOCK 2 |
1415 | #define SQLITE_SHM_SHARED 4 |
1416 | #define SQLITE_SHM_EXCLUSIVE 8 |
1417 | |
1418 | /* |
1419 | ** CAPI3REF: Maximum xShmLock index |
1420 | ** |
1421 | ** The xShmLock method on [sqlite3_io_methods] may use values |
1422 | ** between 0 and this upper bound as its "offset" argument. |
1423 | ** The SQLite core will never attempt to acquire or release a |
1424 | ** lock outside of this range |
1425 | */ |
1426 | #define SQLITE_SHM_NLOCK 8 |
1427 | |
1428 | |
1429 | /* |
1430 | ** CAPI3REF: Initialize The SQLite Library |
1431 | ** |
1432 | ** ^The sqlite3_initialize() routine initializes the |
1433 | ** SQLite library. ^The sqlite3_shutdown() routine |
1434 | ** deallocates any resources that were allocated by sqlite3_initialize(). |
1435 | ** These routines are designed to aid in process initialization and |
1436 | ** shutdown on embedded systems. Workstation applications using |
1437 | ** SQLite normally do not need to invoke either of these routines. |
1438 | ** |
1439 | ** A call to sqlite3_initialize() is an "effective" call if it is |
1440 | ** the first time sqlite3_initialize() is invoked during the lifetime of |
1441 | ** the process, or if it is the first time sqlite3_initialize() is invoked |
1442 | ** following a call to sqlite3_shutdown(). ^(Only an effective call |
1443 | ** of sqlite3_initialize() does any initialization. All other calls |
1444 | ** are harmless no-ops.)^ |
1445 | ** |
1446 | ** A call to sqlite3_shutdown() is an "effective" call if it is the first |
1447 | ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only |
1448 | ** an effective call to sqlite3_shutdown() does any deinitialization. |
1449 | ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^ |
1450 | ** |
1451 | ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown() |
1452 | ** is not. The sqlite3_shutdown() interface must only be called from a |
1453 | ** single thread. All open [database connections] must be closed and all |
1454 | ** other SQLite resources must be deallocated prior to invoking |
1455 | ** sqlite3_shutdown(). |
1456 | ** |
1457 | ** Among other things, ^sqlite3_initialize() will invoke |
1458 | ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown() |
1459 | ** will invoke sqlite3_os_end(). |
1460 | ** |
1461 | ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success. |
1462 | ** ^If for some reason, sqlite3_initialize() is unable to initialize |
1463 | ** the library (perhaps it is unable to allocate a needed resource such |
1464 | ** as a mutex) it returns an [error code] other than [SQLITE_OK]. |
1465 | ** |
1466 | ** ^The sqlite3_initialize() routine is called internally by many other |
1467 | ** SQLite interfaces so that an application usually does not need to |
1468 | ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] |
1469 | ** calls sqlite3_initialize() so the SQLite library will be automatically |
1470 | ** initialized when [sqlite3_open()] is called if it has not be initialized |
1471 | ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] |
1472 | ** compile-time option, then the automatic calls to sqlite3_initialize() |
1473 | ** are omitted and the application must call sqlite3_initialize() directly |
1474 | ** prior to using any other SQLite interface. For maximum portability, |
1475 | ** it is recommended that applications always invoke sqlite3_initialize() |
1476 | ** directly prior to using any other SQLite interface. Future releases |
1477 | ** of SQLite may require this. In other words, the behavior exhibited |
1478 | ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the |
1479 | ** default behavior in some future release of SQLite. |
1480 | ** |
1481 | ** The sqlite3_os_init() routine does operating-system specific |
1482 | ** initialization of the SQLite library. The sqlite3_os_end() |
1483 | ** routine undoes the effect of sqlite3_os_init(). Typical tasks |
1484 | ** performed by these routines include allocation or deallocation |
1485 | ** of static resources, initialization of global variables, |
1486 | ** setting up a default [sqlite3_vfs] module, or setting up |
1487 | ** a default configuration using [sqlite3_config()]. |
1488 | ** |
1489 | ** The application should never invoke either sqlite3_os_init() |
1490 | ** or sqlite3_os_end() directly. The application should only invoke |
1491 | ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() |
1492 | ** interface is called automatically by sqlite3_initialize() and |
1493 | ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate |
1494 | ** implementations for sqlite3_os_init() and sqlite3_os_end() |
1495 | ** are built into SQLite when it is compiled for Unix, Windows, or OS/2. |
1496 | ** When [custom builds | built for other platforms] |
1497 | ** (using the [SQLITE_OS_OTHER=1] compile-time |
1498 | ** option) the application must supply a suitable implementation for |
1499 | ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied |
1500 | ** implementation of sqlite3_os_init() or sqlite3_os_end() |
1501 | ** must return [SQLITE_OK] on success and some other [error code] upon |
1502 | ** failure. |
1503 | */ |
1504 | SQLITE_API int sqlite3_initialize(void); |
1505 | SQLITE_API int sqlite3_shutdown(void); |
1506 | SQLITE_API int sqlite3_os_init(void); |
1507 | SQLITE_API int sqlite3_os_end(void); |
1508 | |
1509 | /* |
1510 | ** CAPI3REF: Configuring The SQLite Library |
1511 | ** |
1512 | ** The sqlite3_config() interface is used to make global configuration |
1513 | ** changes to SQLite in order to tune SQLite to the specific needs of |
1514 | ** the application. The default configuration is recommended for most |
1515 | ** applications and so this routine is usually not necessary. It is |
1516 | ** provided to support rare applications with unusual needs. |
1517 | ** |
1518 | ** <b>The sqlite3_config() interface is not threadsafe. The application |
1519 | ** must ensure that no other SQLite interfaces are invoked by other |
1520 | ** threads while sqlite3_config() is running.</b> |
1521 | ** |
1522 | ** The sqlite3_config() interface |
1523 | ** may only be invoked prior to library initialization using |
1524 | ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. |
1525 | ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before |
1526 | ** [sqlite3_shutdown()] then it will return SQLITE_MISUSE. |
1527 | ** Note, however, that ^sqlite3_config() can be called as part of the |
1528 | ** implementation of an application-defined [sqlite3_os_init()]. |
1529 | ** |
1530 | ** The first argument to sqlite3_config() is an integer |
1531 | ** [configuration option] that determines |
1532 | ** what property of SQLite is to be configured. Subsequent arguments |
1533 | ** vary depending on the [configuration option] |
1534 | ** in the first argument. |
1535 | ** |
1536 | ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. |
1537 | ** ^If the option is unknown or SQLite is unable to set the option |
1538 | ** then this routine returns a non-zero [error code]. |
1539 | */ |
1540 | SQLITE_API int sqlite3_config(int, ...); |
1541 | |
1542 | /* |
1543 | ** CAPI3REF: Configure database connections |
1544 | ** METHOD: sqlite3 |
1545 | ** |
1546 | ** The sqlite3_db_config() interface is used to make configuration |
1547 | ** changes to a [database connection]. The interface is similar to |
1548 | ** [sqlite3_config()] except that the changes apply to a single |
1549 | ** [database connection] (specified in the first argument). |
1550 | ** |
1551 | ** The second argument to sqlite3_db_config(D,V,...) is the |
1552 | ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code |
1553 | ** that indicates what aspect of the [database connection] is being configured. |
1554 | ** Subsequent arguments vary depending on the configuration verb. |
1555 | ** |
1556 | ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if |
1557 | ** the call is considered successful. |
1558 | */ |
1559 | SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...); |
1560 | |
1561 | /* |
1562 | ** CAPI3REF: Memory Allocation Routines |
1563 | ** |
1564 | ** An instance of this object defines the interface between SQLite |
1565 | ** and low-level memory allocation routines. |
1566 | ** |
1567 | ** This object is used in only one place in the SQLite interface. |
1568 | ** A pointer to an instance of this object is the argument to |
1569 | ** [sqlite3_config()] when the configuration option is |
1570 | ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. |
1571 | ** By creating an instance of this object |
1572 | ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) |
1573 | ** during configuration, an application can specify an alternative |
1574 | ** memory allocation subsystem for SQLite to use for all of its |
1575 | ** dynamic memory needs. |
1576 | ** |
1577 | ** Note that SQLite comes with several [built-in memory allocators] |
1578 | ** that are perfectly adequate for the overwhelming majority of applications |
1579 | ** and that this object is only useful to a tiny minority of applications |
1580 | ** with specialized memory allocation requirements. This object is |
1581 | ** also used during testing of SQLite in order to specify an alternative |
1582 | ** memory allocator that simulates memory out-of-memory conditions in |
1583 | ** order to verify that SQLite recovers gracefully from such |
1584 | ** conditions. |
1585 | ** |
1586 | ** The xMalloc, xRealloc, and xFree methods must work like the |
1587 | ** malloc(), realloc() and free() functions from the standard C library. |
1588 | ** ^SQLite guarantees that the second argument to |
1589 | ** xRealloc is always a value returned by a prior call to xRoundup. |
1590 | ** |
1591 | ** xSize should return the allocated size of a memory allocation |
1592 | ** previously obtained from xMalloc or xRealloc. The allocated size |
1593 | ** is always at least as big as the requested size but may be larger. |
1594 | ** |
1595 | ** The xRoundup method returns what would be the allocated size of |
1596 | ** a memory allocation given a particular requested size. Most memory |
1597 | ** allocators round up memory allocations at least to the next multiple |
1598 | ** of 8. Some allocators round up to a larger multiple or to a power of 2. |
1599 | ** Every memory allocation request coming in through [sqlite3_malloc()] |
1600 | ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, |
1601 | ** that causes the corresponding memory allocation to fail. |
1602 | ** |
1603 | ** The xInit method initializes the memory allocator. For example, |
1604 | ** it might allocate any require mutexes or initialize internal data |
1605 | ** structures. The xShutdown method is invoked (indirectly) by |
1606 | ** [sqlite3_shutdown()] and should deallocate any resources acquired |
1607 | ** by xInit. The pAppData pointer is used as the only parameter to |
1608 | ** xInit and xShutdown. |
1609 | ** |
1610 | ** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes |
1611 | ** the xInit method, so the xInit method need not be threadsafe. The |
1612 | ** xShutdown method is only called from [sqlite3_shutdown()] so it does |
1613 | ** not need to be threadsafe either. For all other methods, SQLite |
1614 | ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the |
1615 | ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which |
1616 | ** it is by default) and so the methods are automatically serialized. |
1617 | ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other |
1618 | ** methods must be threadsafe or else make their own arrangements for |
1619 | ** serialization. |
1620 | ** |
1621 | ** SQLite will never invoke xInit() more than once without an intervening |
1622 | ** call to xShutdown(). |
1623 | */ |
1624 | typedef struct sqlite3_mem_methods sqlite3_mem_methods; |
1625 | struct sqlite3_mem_methods { |
1626 | void *(*xMalloc)(int); /* Memory allocation function */ |
1627 | void (*xFree)(void*); /* Free a prior allocation */ |
1628 | void *(*xRealloc)(void*,int); /* Resize an allocation */ |
1629 | int (*xSize)(void*); /* Return the size of an allocation */ |
1630 | int (*xRoundup)(int); /* Round up request size to allocation size */ |
1631 | int (*xInit)(void*); /* Initialize the memory allocator */ |
1632 | void (*xShutdown)(void*); /* Deinitialize the memory allocator */ |
1633 | void *pAppData; /* Argument to xInit() and xShutdown() */ |
1634 | }; |
1635 | |
1636 | /* |
1637 | ** CAPI3REF: Configuration Options |
1638 | ** KEYWORDS: {configuration option} |
1639 | ** |
1640 | ** These constants are the available integer configuration options that |
1641 | ** can be passed as the first argument to the [sqlite3_config()] interface. |
1642 | ** |
1643 | ** New configuration options may be added in future releases of SQLite. |
1644 | ** Existing configuration options might be discontinued. Applications |
1645 | ** should check the return code from [sqlite3_config()] to make sure that |
1646 | ** the call worked. The [sqlite3_config()] interface will return a |
1647 | ** non-zero [error code] if a discontinued or unsupported configuration option |
1648 | ** is invoked. |
1649 | ** |
1650 | ** <dl> |
1651 | ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt> |
1652 | ** <dd>There are no arguments to this option. ^This option sets the |
1653 | ** [threading mode] to Single-thread. In other words, it disables |
1654 | ** all mutexing and puts SQLite into a mode where it can only be used |
1655 | ** by a single thread. ^If SQLite is compiled with |
1656 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
1657 | ** it is not possible to change the [threading mode] from its default |
1658 | ** value of Single-thread and so [sqlite3_config()] will return |
1659 | ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD |
1660 | ** configuration option.</dd> |
1661 | ** |
1662 | ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt> |
1663 | ** <dd>There are no arguments to this option. ^This option sets the |
1664 | ** [threading mode] to Multi-thread. In other words, it disables |
1665 | ** mutexing on [database connection] and [prepared statement] objects. |
1666 | ** The application is responsible for serializing access to |
1667 | ** [database connections] and [prepared statements]. But other mutexes |
1668 | ** are enabled so that SQLite will be safe to use in a multi-threaded |
1669 | ** environment as long as no two threads attempt to use the same |
1670 | ** [database connection] at the same time. ^If SQLite is compiled with |
1671 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
1672 | ** it is not possible to set the Multi-thread [threading mode] and |
1673 | ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the |
1674 | ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd> |
1675 | ** |
1676 | ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt> |
1677 | ** <dd>There are no arguments to this option. ^This option sets the |
1678 | ** [threading mode] to Serialized. In other words, this option enables |
1679 | ** all mutexes including the recursive |
1680 | ** mutexes on [database connection] and [prepared statement] objects. |
1681 | ** In this mode (which is the default when SQLite is compiled with |
1682 | ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access |
1683 | ** to [database connections] and [prepared statements] so that the |
1684 | ** application is free to use the same [database connection] or the |
1685 | ** same [prepared statement] in different threads at the same time. |
1686 | ** ^If SQLite is compiled with |
1687 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
1688 | ** it is not possible to set the Serialized [threading mode] and |
1689 | ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the |
1690 | ** SQLITE_CONFIG_SERIALIZED configuration option.</dd> |
1691 | ** |
1692 | ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt> |
1693 | ** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is |
1694 | ** a pointer to an instance of the [sqlite3_mem_methods] structure. |
1695 | ** The argument specifies |
1696 | ** alternative low-level memory allocation routines to be used in place of |
1697 | ** the memory allocation routines built into SQLite.)^ ^SQLite makes |
1698 | ** its own private copy of the content of the [sqlite3_mem_methods] structure |
1699 | ** before the [sqlite3_config()] call returns.</dd> |
1700 | ** |
1701 | ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt> |
1702 | ** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which |
1703 | ** is a pointer to an instance of the [sqlite3_mem_methods] structure. |
1704 | ** The [sqlite3_mem_methods] |
1705 | ** structure is filled with the currently defined memory allocation routines.)^ |
1706 | ** This option can be used to overload the default memory allocation |
1707 | ** routines with a wrapper that simulations memory allocation failure or |
1708 | ** tracks memory usage, for example. </dd> |
1709 | ** |
1710 | ** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt> |
1711 | ** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of |
1712 | ** type int, interpreted as a boolean, which if true provides a hint to |
1713 | ** SQLite that it should avoid large memory allocations if possible. |
1714 | ** SQLite will run faster if it is free to make large memory allocations, |
1715 | ** but some application might prefer to run slower in exchange for |
1716 | ** guarantees about memory fragmentation that are possible if large |
1717 | ** allocations are avoided. This hint is normally off. |
1718 | ** </dd> |
1719 | ** |
1720 | ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt> |
1721 | ** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int, |
1722 | ** interpreted as a boolean, which enables or disables the collection of |
1723 | ** memory allocation statistics. ^(When memory allocation statistics are |
1724 | ** disabled, the following SQLite interfaces become non-operational: |
1725 | ** <ul> |
1726 | ** <li> [sqlite3_memory_used()] |
1727 | ** <li> [sqlite3_memory_highwater()] |
1728 | ** <li> [sqlite3_soft_heap_limit64()] |
1729 | ** <li> [sqlite3_status64()] |
1730 | ** </ul>)^ |
1731 | ** ^Memory allocation statistics are enabled by default unless SQLite is |
1732 | ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory |
1733 | ** allocation statistics are disabled by default. |
1734 | ** </dd> |
1735 | ** |
1736 | ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt> |
1737 | ** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used. |
1738 | ** </dd> |
1739 | ** |
1740 | ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt> |
1741 | ** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool |
1742 | ** that SQLite can use for the database page cache with the default page |
1743 | ** cache implementation. |
1744 | ** This configuration option is a no-op if an application-define page |
1745 | ** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2]. |
1746 | ** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to |
1747 | ** 8-byte aligned memory (pMem), the size of each page cache line (sz), |
1748 | ** and the number of cache lines (N). |
1749 | ** The sz argument should be the size of the largest database page |
1750 | ** (a power of two between 512 and 65536) plus some extra bytes for each |
1751 | ** page header. ^The number of extra bytes needed by the page header |
1752 | ** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ]. |
1753 | ** ^It is harmless, apart from the wasted memory, |
1754 | ** for the sz parameter to be larger than necessary. The pMem |
1755 | ** argument must be either a NULL pointer or a pointer to an 8-byte |
1756 | ** aligned block of memory of at least sz*N bytes, otherwise |
1757 | ** subsequent behavior is undefined. |
1758 | ** ^When pMem is not NULL, SQLite will strive to use the memory provided |
1759 | ** to satisfy page cache needs, falling back to [sqlite3_malloc()] if |
1760 | ** a page cache line is larger than sz bytes or if all of the pMem buffer |
1761 | ** is exhausted. |
1762 | ** ^If pMem is NULL and N is non-zero, then each database connection |
1763 | ** does an initial bulk allocation for page cache memory |
1764 | ** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or |
1765 | ** of -1024*N bytes if N is negative, . ^If additional |
1766 | ** page cache memory is needed beyond what is provided by the initial |
1767 | ** allocation, then SQLite goes to [sqlite3_malloc()] separately for each |
1768 | ** additional cache line. </dd> |
1769 | ** |
1770 | ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt> |
1771 | ** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer |
1772 | ** that SQLite will use for all of its dynamic memory allocation needs |
1773 | ** beyond those provided for by [SQLITE_CONFIG_PAGECACHE]. |
1774 | ** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled |
1775 | ** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns |
1776 | ** [SQLITE_ERROR] if invoked otherwise. |
1777 | ** ^There are three arguments to SQLITE_CONFIG_HEAP: |
1778 | ** An 8-byte aligned pointer to the memory, |
1779 | ** the number of bytes in the memory buffer, and the minimum allocation size. |
1780 | ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts |
1781 | ** to using its default memory allocator (the system malloc() implementation), |
1782 | ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the |
1783 | ** memory pointer is not NULL then the alternative memory |
1784 | ** allocator is engaged to handle all of SQLites memory allocation needs. |
1785 | ** The first pointer (the memory pointer) must be aligned to an 8-byte |
1786 | ** boundary or subsequent behavior of SQLite will be undefined. |
1787 | ** The minimum allocation size is capped at 2**12. Reasonable values |
1788 | ** for the minimum allocation size are 2**5 through 2**8.</dd> |
1789 | ** |
1790 | ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt> |
1791 | ** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a |
1792 | ** pointer to an instance of the [sqlite3_mutex_methods] structure. |
1793 | ** The argument specifies alternative low-level mutex routines to be used |
1794 | ** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of |
1795 | ** the content of the [sqlite3_mutex_methods] structure before the call to |
1796 | ** [sqlite3_config()] returns. ^If SQLite is compiled with |
1797 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
1798 | ** the entire mutexing subsystem is omitted from the build and hence calls to |
1799 | ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will |
1800 | ** return [SQLITE_ERROR].</dd> |
1801 | ** |
1802 | ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt> |
1803 | ** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which |
1804 | ** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The |
1805 | ** [sqlite3_mutex_methods] |
1806 | ** structure is filled with the currently defined mutex routines.)^ |
1807 | ** This option can be used to overload the default mutex allocation |
1808 | ** routines with a wrapper used to track mutex usage for performance |
1809 | ** profiling or testing, for example. ^If SQLite is compiled with |
1810 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
1811 | ** the entire mutexing subsystem is omitted from the build and hence calls to |
1812 | ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will |
1813 | ** return [SQLITE_ERROR].</dd> |
1814 | ** |
1815 | ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt> |
1816 | ** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine |
1817 | ** the default size of lookaside memory on each [database connection]. |
1818 | ** The first argument is the |
1819 | ** size of each lookaside buffer slot and the second is the number of |
1820 | ** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE |
1821 | ** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] |
1822 | ** option to [sqlite3_db_config()] can be used to change the lookaside |
1823 | ** configuration on individual connections.)^ </dd> |
1824 | ** |
1825 | ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt> |
1826 | ** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is |
1827 | ** a pointer to an [sqlite3_pcache_methods2] object. This object specifies |
1828 | ** the interface to a custom page cache implementation.)^ |
1829 | ** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd> |
1830 | ** |
1831 | ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt> |
1832 | ** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which |
1833 | ** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of |
1834 | ** the current page cache implementation into that object.)^ </dd> |
1835 | ** |
1836 | ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt> |
1837 | ** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite |
1838 | ** global [error log]. |
1839 | ** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a |
1840 | ** function with a call signature of void(*)(void*,int,const char*), |
1841 | ** and a pointer to void. ^If the function pointer is not NULL, it is |
1842 | ** invoked by [sqlite3_log()] to process each logging event. ^If the |
1843 | ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op. |
1844 | ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is |
1845 | ** passed through as the first parameter to the application-defined logger |
1846 | ** function whenever that function is invoked. ^The second parameter to |
1847 | ** the logger function is a copy of the first parameter to the corresponding |
1848 | ** [sqlite3_log()] call and is intended to be a [result code] or an |
1849 | ** [extended result code]. ^The third parameter passed to the logger is |
1850 | ** log message after formatting via [sqlite3_snprintf()]. |
1851 | ** The SQLite logging interface is not reentrant; the logger function |
1852 | ** supplied by the application must not invoke any SQLite interface. |
1853 | ** In a multi-threaded application, the application-defined logger |
1854 | ** function must be threadsafe. </dd> |
1855 | ** |
1856 | ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI |
1857 | ** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int. |
1858 | ** If non-zero, then URI handling is globally enabled. If the parameter is zero, |
1859 | ** then URI handling is globally disabled.)^ ^If URI handling is globally |
1860 | ** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()], |
1861 | ** [sqlite3_open16()] or |
1862 | ** specified as part of [ATTACH] commands are interpreted as URIs, regardless |
1863 | ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database |
1864 | ** connection is opened. ^If it is globally disabled, filenames are |
1865 | ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the |
1866 | ** database connection is opened. ^(By default, URI handling is globally |
1867 | ** disabled. The default value may be changed by compiling with the |
1868 | ** [SQLITE_USE_URI] symbol defined.)^ |
1869 | ** |
1870 | ** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN |
1871 | ** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer |
1872 | ** argument which is interpreted as a boolean in order to enable or disable |
1873 | ** the use of covering indices for full table scans in the query optimizer. |
1874 | ** ^The default setting is determined |
1875 | ** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on" |
1876 | ** if that compile-time option is omitted. |
1877 | ** The ability to disable the use of covering indices for full table scans |
1878 | ** is because some incorrectly coded legacy applications might malfunction |
1879 | ** when the optimization is enabled. Providing the ability to |
1880 | ** disable the optimization allows the older, buggy application code to work |
1881 | ** without change even with newer versions of SQLite. |
1882 | ** |
1883 | ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]] |
1884 | ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE |
1885 | ** <dd> These options are obsolete and should not be used by new code. |
1886 | ** They are retained for backwards compatibility but are now no-ops. |
1887 | ** </dd> |
1888 | ** |
1889 | ** [[SQLITE_CONFIG_SQLLOG]] |
1890 | ** <dt>SQLITE_CONFIG_SQLLOG |
1891 | ** <dd>This option is only available if sqlite is compiled with the |
1892 | ** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should |
1893 | ** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int). |
1894 | ** The second should be of type (void*). The callback is invoked by the library |
1895 | ** in three separate circumstances, identified by the value passed as the |
1896 | ** fourth parameter. If the fourth parameter is 0, then the database connection |
1897 | ** passed as the second argument has just been opened. The third argument |
1898 | ** points to a buffer containing the name of the main database file. If the |
1899 | ** fourth parameter is 1, then the SQL statement that the third parameter |
1900 | ** points to has just been executed. Or, if the fourth parameter is 2, then |
1901 | ** the connection being passed as the second parameter is being closed. The |
1902 | ** third parameter is passed NULL In this case. An example of using this |
1903 | ** configuration option can be seen in the "test_sqllog.c" source file in |
1904 | ** the canonical SQLite source tree.</dd> |
1905 | ** |
1906 | ** [[SQLITE_CONFIG_MMAP_SIZE]] |
1907 | ** <dt>SQLITE_CONFIG_MMAP_SIZE |
1908 | ** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values |
1909 | ** that are the default mmap size limit (the default setting for |
1910 | ** [PRAGMA mmap_size]) and the maximum allowed mmap size limit. |
1911 | ** ^The default setting can be overridden by each database connection using |
1912 | ** either the [PRAGMA mmap_size] command, or by using the |
1913 | ** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size |
1914 | ** will be silently truncated if necessary so that it does not exceed the |
1915 | ** compile-time maximum mmap size set by the |
1916 | ** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^ |
1917 | ** ^If either argument to this option is negative, then that argument is |
1918 | ** changed to its compile-time default. |
1919 | ** |
1920 | ** [[SQLITE_CONFIG_WIN32_HEAPSIZE]] |
1921 | ** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE |
1922 | ** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is |
1923 | ** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro |
1924 | ** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value |
1925 | ** that specifies the maximum size of the created heap. |
1926 | ** |
1927 | ** [[SQLITE_CONFIG_PCACHE_HDRSZ]] |
1928 | ** <dt>SQLITE_CONFIG_PCACHE_HDRSZ |
1929 | ** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which |
1930 | ** is a pointer to an integer and writes into that integer the number of extra |
1931 | ** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE]. |
1932 | ** The amount of extra space required can change depending on the compiler, |
1933 | ** target platform, and SQLite version. |
1934 | ** |
1935 | ** [[SQLITE_CONFIG_PMASZ]] |
1936 | ** <dt>SQLITE_CONFIG_PMASZ |
1937 | ** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which |
1938 | ** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded |
1939 | ** sorter to that integer. The default minimum PMA Size is set by the |
1940 | ** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched |
1941 | ** to help with sort operations when multithreaded sorting |
1942 | ** is enabled (using the [PRAGMA threads] command) and the amount of content |
1943 | ** to be sorted exceeds the page size times the minimum of the |
1944 | ** [PRAGMA cache_size] setting and this value. |
1945 | ** |
1946 | ** [[SQLITE_CONFIG_STMTJRNL_SPILL]] |
1947 | ** <dt>SQLITE_CONFIG_STMTJRNL_SPILL |
1948 | ** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which |
1949 | ** becomes the [statement journal] spill-to-disk threshold. |
1950 | ** [Statement journals] are held in memory until their size (in bytes) |
1951 | ** exceeds this threshold, at which point they are written to disk. |
1952 | ** Or if the threshold is -1, statement journals are always held |
1953 | ** exclusively in memory. |
1954 | ** Since many statement journals never become large, setting the spill |
1955 | ** threshold to a value such as 64KiB can greatly reduce the amount of |
1956 | ** I/O required to support statement rollback. |
1957 | ** The default value for this setting is controlled by the |
1958 | ** [SQLITE_STMTJRNL_SPILL] compile-time option. |
1959 | ** |
1960 | ** [[SQLITE_CONFIG_SORTERREF_SIZE]] |
1961 | ** <dt>SQLITE_CONFIG_SORTERREF_SIZE |
1962 | ** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter |
1963 | ** of type (int) - the new value of the sorter-reference size threshold. |
1964 | ** Usually, when SQLite uses an external sort to order records according |
1965 | ** to an ORDER BY clause, all fields required by the caller are present in the |
1966 | ** sorted records. However, if SQLite determines based on the declared type |
1967 | ** of a table column that its values are likely to be very large - larger |
1968 | ** than the configured sorter-reference size threshold - then a reference |
1969 | ** is stored in each sorted record and the required column values loaded |
1970 | ** from the database as records are returned in sorted order. The default |
1971 | ** value for this option is to never use this optimization. Specifying a |
1972 | ** negative value for this option restores the default behaviour. |
1973 | ** This option is only available if SQLite is compiled with the |
1974 | ** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option. |
1975 | ** </dl> |
1976 | */ |
1977 | #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ |
1978 | #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ |
1979 | #define SQLITE_CONFIG_SERIALIZED 3 /* nil */ |
1980 | #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ |
1981 | #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ |
1982 | #define SQLITE_CONFIG_SCRATCH 6 /* No longer used */ |
1983 | #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ |
1984 | #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ |
1985 | #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ |
1986 | #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ |
1987 | #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ |
1988 | /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ |
1989 | #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ |
1990 | #define SQLITE_CONFIG_PCACHE 14 /* no-op */ |
1991 | #define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ |
1992 | #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ |
1993 | #define SQLITE_CONFIG_URI 17 /* int */ |
1994 | #define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ |
1995 | #define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ |
1996 | #define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */ |
1997 | #define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */ |
1998 | #define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */ |
1999 | #define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */ |
2000 | #define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */ |
2001 | #define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */ |
2002 | #define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */ |
2003 | #define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */ |
2004 | #define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */ |
2005 | |
2006 | /* |
2007 | ** CAPI3REF: Database Connection Configuration Options |
2008 | ** |
2009 | ** These constants are the available integer configuration options that |
2010 | ** can be passed as the second argument to the [sqlite3_db_config()] interface. |
2011 | ** |
2012 | ** New configuration options may be added in future releases of SQLite. |
2013 | ** Existing configuration options might be discontinued. Applications |
2014 | ** should check the return code from [sqlite3_db_config()] to make sure that |
2015 | ** the call worked. ^The [sqlite3_db_config()] interface will return a |
2016 | ** non-zero [error code] if a discontinued or unsupported configuration option |
2017 | ** is invoked. |
2018 | ** |
2019 | ** <dl> |
2020 | ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt> |
2021 | ** <dd> ^This option takes three additional arguments that determine the |
2022 | ** [lookaside memory allocator] configuration for the [database connection]. |
2023 | ** ^The first argument (the third parameter to [sqlite3_db_config()] is a |
2024 | ** pointer to a memory buffer to use for lookaside memory. |
2025 | ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb |
2026 | ** may be NULL in which case SQLite will allocate the |
2027 | ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the |
2028 | ** size of each lookaside buffer slot. ^The third argument is the number of |
2029 | ** slots. The size of the buffer in the first argument must be greater than |
2030 | ** or equal to the product of the second and third arguments. The buffer |
2031 | ** must be aligned to an 8-byte boundary. ^If the second argument to |
2032 | ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally |
2033 | ** rounded down to the next smaller multiple of 8. ^(The lookaside memory |
2034 | ** configuration for a database connection can only be changed when that |
2035 | ** connection is not currently using lookaside memory, or in other words |
2036 | ** when the "current value" returned by |
2037 | ** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero. |
2038 | ** Any attempt to change the lookaside memory configuration when lookaside |
2039 | ** memory is in use leaves the configuration unchanged and returns |
2040 | ** [SQLITE_BUSY].)^</dd> |
2041 | ** |
2042 | ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt> |
2043 | ** <dd> ^This option is used to enable or disable the enforcement of |
2044 | ** [foreign key constraints]. There should be two additional arguments. |
2045 | ** The first argument is an integer which is 0 to disable FK enforcement, |
2046 | ** positive to enable FK enforcement or negative to leave FK enforcement |
2047 | ** unchanged. The second parameter is a pointer to an integer into which |
2048 | ** is written 0 or 1 to indicate whether FK enforcement is off or on |
2049 | ** following this call. The second parameter may be a NULL pointer, in |
2050 | ** which case the FK enforcement setting is not reported back. </dd> |
2051 | ** |
2052 | ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt> |
2053 | ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers]. |
2054 | ** There should be two additional arguments. |
2055 | ** The first argument is an integer which is 0 to disable triggers, |
2056 | ** positive to enable triggers or negative to leave the setting unchanged. |
2057 | ** The second parameter is a pointer to an integer into which |
2058 | ** is written 0 or 1 to indicate whether triggers are disabled or enabled |
2059 | ** following this call. The second parameter may be a NULL pointer, in |
2060 | ** which case the trigger setting is not reported back. </dd> |
2061 | ** |
2062 | ** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt> |
2063 | ** <dd> ^This option is used to enable or disable the two-argument |
2064 | ** version of the [fts3_tokenizer()] function which is part of the |
2065 | ** [FTS3] full-text search engine extension. |
2066 | ** There should be two additional arguments. |
2067 | ** The first argument is an integer which is 0 to disable fts3_tokenizer() or |
2068 | ** positive to enable fts3_tokenizer() or negative to leave the setting |
2069 | ** unchanged. |
2070 | ** The second parameter is a pointer to an integer into which |
2071 | ** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled |
2072 | ** following this call. The second parameter may be a NULL pointer, in |
2073 | ** which case the new setting is not reported back. </dd> |
2074 | ** |
2075 | ** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt> |
2076 | ** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()] |
2077 | ** interface independently of the [load_extension()] SQL function. |
2078 | ** The [sqlite3_enable_load_extension()] API enables or disables both the |
2079 | ** C-API [sqlite3_load_extension()] and the SQL function [load_extension()]. |
2080 | ** There should be two additional arguments. |
2081 | ** When the first argument to this interface is 1, then only the C-API is |
2082 | ** enabled and the SQL function remains disabled. If the first argument to |
2083 | ** this interface is 0, then both the C-API and the SQL function are disabled. |
2084 | ** If the first argument is -1, then no changes are made to state of either the |
2085 | ** C-API or the SQL function. |
2086 | ** The second parameter is a pointer to an integer into which |
2087 | ** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface |
2088 | ** is disabled or enabled following this call. The second parameter may |
2089 | ** be a NULL pointer, in which case the new setting is not reported back. |
2090 | ** </dd> |
2091 | ** |
2092 | ** <dt>SQLITE_DBCONFIG_MAINDBNAME</dt> |
2093 | ** <dd> ^This option is used to change the name of the "main" database |
2094 | ** schema. ^The sole argument is a pointer to a constant UTF8 string |
2095 | ** which will become the new schema name in place of "main". ^SQLite |
2096 | ** does not make a copy of the new main schema name string, so the application |
2097 | ** must ensure that the argument passed into this DBCONFIG option is unchanged |
2098 | ** until after the database connection closes. |
2099 | ** </dd> |
2100 | ** |
2101 | ** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt> |
2102 | ** <dd> Usually, when a database in wal mode is closed or detached from a |
2103 | ** database handle, SQLite checks if this will mean that there are now no |
2104 | ** connections at all to the database. If so, it performs a checkpoint |
2105 | ** operation before closing the connection. This option may be used to |
2106 | ** override this behaviour. The first parameter passed to this operation |
2107 | ** is an integer - positive to disable checkpoints-on-close, or zero (the |
2108 | ** default) to enable them, and negative to leave the setting unchanged. |
2109 | ** The second parameter is a pointer to an integer |
2110 | ** into which is written 0 or 1 to indicate whether checkpoints-on-close |
2111 | ** have been disabled - 0 if they are not disabled, 1 if they are. |
2112 | ** </dd> |
2113 | ** |
2114 | ** <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt> |
2115 | ** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates |
2116 | ** the [query planner stability guarantee] (QPSG). When the QPSG is active, |
2117 | ** a single SQL query statement will always use the same algorithm regardless |
2118 | ** of values of [bound parameters].)^ The QPSG disables some query optimizations |
2119 | ** that look at the values of bound parameters, which can make some queries |
2120 | ** slower. But the QPSG has the advantage of more predictable behavior. With |
2121 | ** the QPSG active, SQLite will always use the same query plan in the field as |
2122 | ** was used during testing in the lab. |
2123 | ** The first argument to this setting is an integer which is 0 to disable |
2124 | ** the QPSG, positive to enable QPSG, or negative to leave the setting |
2125 | ** unchanged. The second parameter is a pointer to an integer into which |
2126 | ** is written 0 or 1 to indicate whether the QPSG is disabled or enabled |
2127 | ** following this call. |
2128 | ** </dd> |
2129 | ** |
2130 | ** <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt> |
2131 | ** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not |
2132 | ** include output for any operations performed by trigger programs. This |
2133 | ** option is used to set or clear (the default) a flag that governs this |
2134 | ** behavior. The first parameter passed to this operation is an integer - |
2135 | ** positive to enable output for trigger programs, or zero to disable it, |
2136 | ** or negative to leave the setting unchanged. |
2137 | ** The second parameter is a pointer to an integer into which is written |
2138 | ** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if |
2139 | ** it is not disabled, 1 if it is. |
2140 | ** </dd> |
2141 | ** |
2142 | ** <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt> |
2143 | ** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run |
2144 | ** [VACUUM] in order to reset a database back to an empty database |
2145 | ** with no schema and no content. The following process works even for |
2146 | ** a badly corrupted database file: |
2147 | ** <ol> |
2148 | ** <li> If the database connection is newly opened, make sure it has read the |
2149 | ** database schema by preparing then discarding some query against the |
2150 | ** database, or calling sqlite3_table_column_metadata(), ignoring any |
2151 | ** errors. This step is only necessary if the application desires to keep |
2152 | ** the database in WAL mode after the reset if it was in WAL mode before |
2153 | ** the reset. |
2154 | ** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0); |
2155 | ** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0); |
2156 | ** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0); |
2157 | ** </ol> |
2158 | ** Because resetting a database is destructive and irreversible, the |
2159 | ** process requires the use of this obscure API and multiple steps to help |
2160 | ** ensure that it does not happen by accident. |
2161 | ** </dd> |
2162 | ** </dl> |
2163 | */ |
2164 | #define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */ |
2165 | #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ |
2166 | #define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */ |
2167 | #define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */ |
2168 | #define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */ |
2169 | #define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */ |
2170 | #define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */ |
2171 | #define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */ |
2172 | #define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */ |
2173 | #define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */ |
2174 | #define SQLITE_DBCONFIG_MAX 1009 /* Largest DBCONFIG */ |
2175 | |
2176 | /* |
2177 | ** CAPI3REF: Enable Or Disable Extended Result Codes |
2178 | ** METHOD: sqlite3 |
2179 | ** |
2180 | ** ^The sqlite3_extended_result_codes() routine enables or disables the |
2181 | ** [extended result codes] feature of SQLite. ^The extended result |
2182 | ** codes are disabled by default for historical compatibility. |
2183 | */ |
2184 | SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff); |
2185 | |
2186 | /* |
2187 | ** CAPI3REF: Last Insert Rowid |
2188 | ** METHOD: sqlite3 |
2189 | ** |
2190 | ** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables) |
2191 | ** has a unique 64-bit signed |
2192 | ** integer key called the [ROWID | "rowid"]. ^The rowid is always available |
2193 | ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those |
2194 | ** names are not also used by explicitly declared columns. ^If |
2195 | ** the table has a column of type [INTEGER PRIMARY KEY] then that column |
2196 | ** is another alias for the rowid. |
2197 | ** |
2198 | ** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of |
2199 | ** the most recent successful [INSERT] into a rowid table or [virtual table] |
2200 | ** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not |
2201 | ** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred |
2202 | ** on the database connection D, then sqlite3_last_insert_rowid(D) returns |
2203 | ** zero. |
2204 | ** |
2205 | ** As well as being set automatically as rows are inserted into database |
2206 | ** tables, the value returned by this function may be set explicitly by |
2207 | ** [sqlite3_set_last_insert_rowid()] |
2208 | ** |
2209 | ** Some virtual table implementations may INSERT rows into rowid tables as |
2210 | ** part of committing a transaction (e.g. to flush data accumulated in memory |
2211 | ** to disk). In this case subsequent calls to this function return the rowid |
2212 | ** associated with these internal INSERT operations, which leads to |
2213 | ** unintuitive results. Virtual table implementations that do write to rowid |
2214 | ** tables in this way can avoid this problem by restoring the original |
2215 | ** rowid value using [sqlite3_set_last_insert_rowid()] before returning |
2216 | ** control to the user. |
2217 | ** |
2218 | ** ^(If an [INSERT] occurs within a trigger then this routine will |
2219 | ** return the [rowid] of the inserted row as long as the trigger is |
2220 | ** running. Once the trigger program ends, the value returned |
2221 | ** by this routine reverts to what it was before the trigger was fired.)^ |
2222 | ** |
2223 | ** ^An [INSERT] that fails due to a constraint violation is not a |
2224 | ** successful [INSERT] and does not change the value returned by this |
2225 | ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, |
2226 | ** and INSERT OR ABORT make no changes to the return value of this |
2227 | ** routine when their insertion fails. ^(When INSERT OR REPLACE |
2228 | ** encounters a constraint violation, it does not fail. The |
2229 | ** INSERT continues to completion after deleting rows that caused |
2230 | ** the constraint problem so INSERT OR REPLACE will always change |
2231 | ** the return value of this interface.)^ |
2232 | ** |
2233 | ** ^For the purposes of this routine, an [INSERT] is considered to |
2234 | ** be successful even if it is subsequently rolled back. |
2235 | ** |
2236 | ** This function is accessible to SQL statements via the |
2237 | ** [last_insert_rowid() SQL function]. |
2238 | ** |
2239 | ** If a separate thread performs a new [INSERT] on the same |
2240 | ** database connection while the [sqlite3_last_insert_rowid()] |
2241 | ** function is running and thus changes the last insert [rowid], |
2242 | ** then the value returned by [sqlite3_last_insert_rowid()] is |
2243 | ** unpredictable and might not equal either the old or the new |
2244 | ** last insert [rowid]. |
2245 | */ |
2246 | SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); |
2247 | |
2248 | /* |
2249 | ** CAPI3REF: Set the Last Insert Rowid value. |
2250 | ** METHOD: sqlite3 |
2251 | ** |
2252 | ** The sqlite3_set_last_insert_rowid(D, R) method allows the application to |
2253 | ** set the value returned by calling sqlite3_last_insert_rowid(D) to R |
2254 | ** without inserting a row into the database. |
2255 | */ |
2256 | SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64); |
2257 | |
2258 | /* |
2259 | ** CAPI3REF: Count The Number Of Rows Modified |
2260 | ** METHOD: sqlite3 |
2261 | ** |
2262 | ** ^This function returns the number of rows modified, inserted or |
2263 | ** deleted by the most recently completed INSERT, UPDATE or DELETE |
2264 | ** statement on the database connection specified by the only parameter. |
2265 | ** ^Executing any other type of SQL statement does not modify the value |
2266 | ** returned by this function. |
2267 | ** |
2268 | ** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are |
2269 | ** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], |
2270 | ** [foreign key actions] or [REPLACE] constraint resolution are not counted. |
2271 | ** |
2272 | ** Changes to a view that are intercepted by |
2273 | ** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value |
2274 | ** returned by sqlite3_changes() immediately after an INSERT, UPDATE or |
2275 | ** DELETE statement run on a view is always zero. Only changes made to real |
2276 | ** tables are counted. |
2277 | ** |
2278 | ** Things are more complicated if the sqlite3_changes() function is |
2279 | ** executed while a trigger program is running. This may happen if the |
2280 | ** program uses the [changes() SQL function], or if some other callback |
2281 | ** function invokes sqlite3_changes() directly. Essentially: |
2282 | ** |
2283 | ** <ul> |
2284 | ** <li> ^(Before entering a trigger program the value returned by |
2285 | ** sqlite3_changes() function is saved. After the trigger program |
2286 | ** has finished, the original value is restored.)^ |
2287 | ** |
2288 | ** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE |
2289 | ** statement sets the value returned by sqlite3_changes() |
2290 | ** upon completion as normal. Of course, this value will not include |
2291 | ** any changes performed by sub-triggers, as the sqlite3_changes() |
2292 | ** value will be saved and restored after each sub-trigger has run.)^ |
2293 | ** </ul> |
2294 | ** |
2295 | ** ^This means that if the changes() SQL function (or similar) is used |
2296 | ** by the first INSERT, UPDATE or DELETE statement within a trigger, it |
2297 | ** returns the value as set when the calling statement began executing. |
2298 | ** ^If it is used by the second or subsequent such statement within a trigger |
2299 | ** program, the value returned reflects the number of rows modified by the |
2300 | ** previous INSERT, UPDATE or DELETE statement within the same trigger. |
2301 | ** |
2302 | ** If a separate thread makes changes on the same database connection |
2303 | ** while [sqlite3_changes()] is running then the value returned |
2304 | ** is unpredictable and not meaningful. |
2305 | ** |
2306 | ** See also: |
2307 | ** <ul> |
2308 | ** <li> the [sqlite3_total_changes()] interface |
2309 | ** <li> the [count_changes pragma] |
2310 | ** <li> the [changes() SQL function] |
2311 | ** <li> the [data_version pragma] |
2312 | ** </ul> |
2313 | */ |
2314 | SQLITE_API int sqlite3_changes(sqlite3*); |
2315 | |
2316 | /* |
2317 | ** CAPI3REF: Total Number Of Rows Modified |
2318 | ** METHOD: sqlite3 |
2319 | ** |
2320 | ** ^This function returns the total number of rows inserted, modified or |
2321 | ** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed |
2322 | ** since the database connection was opened, including those executed as |
2323 | ** part of trigger programs. ^Executing any other type of SQL statement |
2324 | ** does not affect the value returned by sqlite3_total_changes(). |
2325 | ** |
2326 | ** ^Changes made as part of [foreign key actions] are included in the |
2327 | ** count, but those made as part of REPLACE constraint resolution are |
2328 | ** not. ^Changes to a view that are intercepted by INSTEAD OF triggers |
2329 | ** are not counted. |
2330 | ** |
2331 | ** This the [sqlite3_total_changes(D)] interface only reports the number |
2332 | ** of rows that changed due to SQL statement run against database |
2333 | ** connection D. Any changes by other database connections are ignored. |
2334 | ** To detect changes against a database file from other database |
2335 | ** connections use the [PRAGMA data_version] command or the |
2336 | ** [SQLITE_FCNTL_DATA_VERSION] [file control]. |
2337 | ** |
2338 | ** If a separate thread makes changes on the same database connection |
2339 | ** while [sqlite3_total_changes()] is running then the value |
2340 | ** returned is unpredictable and not meaningful. |
2341 | ** |
2342 | ** See also: |
2343 | ** <ul> |
2344 | ** <li> the [sqlite3_changes()] interface |
2345 | ** <li> the [count_changes pragma] |
2346 | ** <li> the [changes() SQL function] |
2347 | ** <li> the [data_version pragma] |
2348 | ** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control] |
2349 | ** </ul> |
2350 | */ |
2351 | SQLITE_API int sqlite3_total_changes(sqlite3*); |
2352 | |
2353 | /* |
2354 | ** CAPI3REF: Interrupt A Long-Running Query |
2355 | ** METHOD: sqlite3 |
2356 | ** |
2357 | ** ^This function causes any pending database operation to abort and |
2358 | ** return at its earliest opportunity. This routine is typically |
2359 | ** called in response to a user action such as pressing "Cancel" |
2360 | ** or Ctrl-C where the user wants a long query operation to halt |
2361 | ** immediately. |
2362 | ** |
2363 | ** ^It is safe to call this routine from a thread different from the |
2364 | ** thread that is currently running the database operation. But it |
2365 | ** is not safe to call this routine with a [database connection] that |
2366 | ** is closed or might close before sqlite3_interrupt() returns. |
2367 | ** |
2368 | ** ^If an SQL operation is very nearly finished at the time when |
2369 | ** sqlite3_interrupt() is called, then it might not have an opportunity |
2370 | ** to be interrupted and might continue to completion. |
2371 | ** |
2372 | ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. |
2373 | ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE |
2374 | ** that is inside an explicit transaction, then the entire transaction |
2375 | ** will be rolled back automatically. |
2376 | ** |
2377 | ** ^The sqlite3_interrupt(D) call is in effect until all currently running |
2378 | ** SQL statements on [database connection] D complete. ^Any new SQL statements |
2379 | ** that are started after the sqlite3_interrupt() call and before the |
2380 | ** running statements reaches zero are interrupted as if they had been |
2381 | ** running prior to the sqlite3_interrupt() call. ^New SQL statements |
2382 | ** that are started after the running statement count reaches zero are |
2383 | ** not effected by the sqlite3_interrupt(). |
2384 | ** ^A call to sqlite3_interrupt(D) that occurs when there are no running |
2385 | ** SQL statements is a no-op and has no effect on SQL statements |
2386 | ** that are started after the sqlite3_interrupt() call returns. |
2387 | */ |
2388 | SQLITE_API void sqlite3_interrupt(sqlite3*); |
2389 | |
2390 | /* |
2391 | ** CAPI3REF: Determine If An SQL Statement Is Complete |
2392 | ** |
2393 | ** These routines are useful during command-line input to determine if the |
2394 | ** currently entered text seems to form a complete SQL statement or |
2395 | ** if additional input is needed before sending the text into |
2396 | ** SQLite for parsing. ^These routines return 1 if the input string |
2397 | ** appears to be a complete SQL statement. ^A statement is judged to be |
2398 | ** complete if it ends with a semicolon token and is not a prefix of a |
2399 | ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within |
2400 | ** string literals or quoted identifier names or comments are not |
2401 | ** independent tokens (they are part of the token in which they are |
2402 | ** embedded) and thus do not count as a statement terminator. ^Whitespace |
2403 | ** and comments that follow the final semicolon are ignored. |
2404 | ** |
2405 | ** ^These routines return 0 if the statement is incomplete. ^If a |
2406 | ** memory allocation fails, then SQLITE_NOMEM is returned. |
2407 | ** |
2408 | ** ^These routines do not parse the SQL statements thus |
2409 | ** will not detect syntactically incorrect SQL. |
2410 | ** |
2411 | ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior |
2412 | ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked |
2413 | ** automatically by sqlite3_complete16(). If that initialization fails, |
2414 | ** then the return value from sqlite3_complete16() will be non-zero |
2415 | ** regardless of whether or not the input SQL is complete.)^ |
2416 | ** |
2417 | ** The input to [sqlite3_complete()] must be a zero-terminated |
2418 | ** UTF-8 string. |
2419 | ** |
2420 | ** The input to [sqlite3_complete16()] must be a zero-terminated |
2421 | ** UTF-16 string in native byte order. |
2422 | */ |
2423 | SQLITE_API int sqlite3_complete(const char *sql); |
2424 | SQLITE_API int sqlite3_complete16(const void *sql); |
2425 | |
2426 | /* |
2427 | ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors |
2428 | ** KEYWORDS: {busy-handler callback} {busy handler} |
2429 | ** METHOD: sqlite3 |
2430 | ** |
2431 | ** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X |
2432 | ** that might be invoked with argument P whenever |
2433 | ** an attempt is made to access a database table associated with |
2434 | ** [database connection] D when another thread |
2435 | ** or process has the table locked. |
2436 | ** The sqlite3_busy_handler() interface is used to implement |
2437 | ** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout]. |
2438 | ** |
2439 | ** ^If the busy callback is NULL, then [SQLITE_BUSY] |
2440 | ** is returned immediately upon encountering the lock. ^If the busy callback |
2441 | ** is not NULL, then the callback might be invoked with two arguments. |
2442 | ** |
2443 | ** ^The first argument to the busy handler is a copy of the void* pointer which |
2444 | ** is the third argument to sqlite3_busy_handler(). ^The second argument to |
2445 | ** the busy handler callback is the number of times that the busy handler has |
2446 | ** been invoked previously for the same locking event. ^If the |
2447 | ** busy callback returns 0, then no additional attempts are made to |
2448 | ** access the database and [SQLITE_BUSY] is returned |
2449 | ** to the application. |
2450 | ** ^If the callback returns non-zero, then another attempt |
2451 | ** is made to access the database and the cycle repeats. |
2452 | ** |
2453 | ** The presence of a busy handler does not guarantee that it will be invoked |
2454 | ** when there is lock contention. ^If SQLite determines that invoking the busy |
2455 | ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] |
2456 | ** to the application instead of invoking the |
2457 | ** busy handler. |
2458 | ** Consider a scenario where one process is holding a read lock that |
2459 | ** it is trying to promote to a reserved lock and |
2460 | ** a second process is holding a reserved lock that it is trying |
2461 | ** to promote to an exclusive lock. The first process cannot proceed |
2462 | ** because it is blocked by the second and the second process cannot |
2463 | ** proceed because it is blocked by the first. If both processes |
2464 | ** invoke the busy handlers, neither will make any progress. Therefore, |
2465 | ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this |
2466 | ** will induce the first process to release its read lock and allow |
2467 | ** the second process to proceed. |
2468 | ** |
2469 | ** ^The default busy callback is NULL. |
2470 | ** |
2471 | ** ^(There can only be a single busy handler defined for each |
2472 | ** [database connection]. Setting a new busy handler clears any |
2473 | ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()] |
2474 | ** or evaluating [PRAGMA busy_timeout=N] will change the |
2475 | ** busy handler and thus clear any previously set busy handler. |
2476 | ** |
2477 | ** The busy callback should not take any actions which modify the |
2478 | ** database connection that invoked the busy handler. In other words, |
2479 | ** the busy handler is not reentrant. Any such actions |
2480 | ** result in undefined behavior. |
2481 | ** |
2482 | ** A busy handler must not close the database connection |
2483 | ** or [prepared statement] that invoked the busy handler. |
2484 | */ |
2485 | SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*); |
2486 | |
2487 | /* |
2488 | ** CAPI3REF: Set A Busy Timeout |
2489 | ** METHOD: sqlite3 |
2490 | ** |
2491 | ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps |
2492 | ** for a specified amount of time when a table is locked. ^The handler |
2493 | ** will sleep multiple times until at least "ms" milliseconds of sleeping |
2494 | ** have accumulated. ^After at least "ms" milliseconds of sleeping, |
2495 | ** the handler returns 0 which causes [sqlite3_step()] to return |
2496 | ** [SQLITE_BUSY]. |
2497 | ** |
2498 | ** ^Calling this routine with an argument less than or equal to zero |
2499 | ** turns off all busy handlers. |
2500 | ** |
2501 | ** ^(There can only be a single busy handler for a particular |
2502 | ** [database connection] at any given moment. If another busy handler |
2503 | ** was defined (using [sqlite3_busy_handler()]) prior to calling |
2504 | ** this routine, that other busy handler is cleared.)^ |
2505 | ** |
2506 | ** See also: [PRAGMA busy_timeout] |
2507 | */ |
2508 | SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); |
2509 | |
2510 | /* |
2511 | ** CAPI3REF: Convenience Routines For Running Queries |
2512 | ** METHOD: sqlite3 |
2513 | ** |
2514 | ** This is a legacy interface that is preserved for backwards compatibility. |
2515 | ** Use of this interface is not recommended. |
2516 | ** |
2517 | ** Definition: A <b>result table</b> is memory data structure created by the |
2518 | ** [sqlite3_get_table()] interface. A result table records the |
2519 | ** complete query results from one or more queries. |
2520 | ** |
2521 | ** The table conceptually has a number of rows and columns. But |
2522 | ** these numbers are not part of the result table itself. These |
2523 | ** numbers are obtained separately. Let N be the number of rows |
2524 | ** and M be the number of columns. |
2525 | ** |
2526 | ** A result table is an array of pointers to zero-terminated UTF-8 strings. |
2527 | ** There are (N+1)*M elements in the array. The first M pointers point |
2528 | ** to zero-terminated strings that contain the names of the columns. |
2529 | ** The remaining entries all point to query results. NULL values result |
2530 | ** in NULL pointers. All other values are in their UTF-8 zero-terminated |
2531 | ** string representation as returned by [sqlite3_column_text()]. |
2532 | ** |
2533 | ** A result table might consist of one or more memory allocations. |
2534 | ** It is not safe to pass a result table directly to [sqlite3_free()]. |
2535 | ** A result table should be deallocated using [sqlite3_free_table()]. |
2536 | ** |
2537 | ** ^(As an example of the result table format, suppose a query result |
2538 | ** is as follows: |
2539 | ** |
2540 | ** <blockquote><pre> |
2541 | ** Name | Age |
2542 | ** ----------------------- |
2543 | ** Alice | 43 |
2544 | ** Bob | 28 |
2545 | ** Cindy | 21 |
2546 | ** </pre></blockquote> |
2547 | ** |
2548 | ** There are two column (M==2) and three rows (N==3). Thus the |
2549 | ** result table has 8 entries. Suppose the result table is stored |
2550 | ** in an array names azResult. Then azResult holds this content: |
2551 | ** |
2552 | ** <blockquote><pre> |
2553 | ** azResult[0] = "Name"; |
2554 | ** azResult[1] = "Age"; |
2555 | ** azResult[2] = "Alice"; |
2556 | ** azResult[3] = "43"; |
2557 | ** azResult[4] = "Bob"; |
2558 | ** azResult[5] = "28"; |
2559 | ** azResult[6] = "Cindy"; |
2560 | ** azResult[7] = "21"; |
2561 | ** </pre></blockquote>)^ |
2562 | ** |
2563 | ** ^The sqlite3_get_table() function evaluates one or more |
2564 | ** semicolon-separated SQL statements in the zero-terminated UTF-8 |
2565 | ** string of its 2nd parameter and returns a result table to the |
2566 | ** pointer given in its 3rd parameter. |
2567 | ** |
2568 | ** After the application has finished with the result from sqlite3_get_table(), |
2569 | ** it must pass the result table pointer to sqlite3_free_table() in order to |
2570 | ** release the memory that was malloced. Because of the way the |
2571 | ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling |
2572 | ** function must not try to call [sqlite3_free()] directly. Only |
2573 | ** [sqlite3_free_table()] is able to release the memory properly and safely. |
2574 | ** |
2575 | ** The sqlite3_get_table() interface is implemented as a wrapper around |
2576 | ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access |
2577 | ** to any internal data structures of SQLite. It uses only the public |
2578 | ** interface defined here. As a consequence, errors that occur in the |
2579 | ** wrapper layer outside of the internal [sqlite3_exec()] call are not |
2580 | ** reflected in subsequent calls to [sqlite3_errcode()] or |
2581 | ** [sqlite3_errmsg()]. |
2582 | */ |
2583 | SQLITE_API int sqlite3_get_table( |
2584 | sqlite3 *db, /* An open database */ |
2585 | const char *zSql, /* SQL to be evaluated */ |
2586 | char ***pazResult, /* Results of the query */ |
2587 | int *pnRow, /* Number of result rows written here */ |
2588 | int *pnColumn, /* Number of result columns written here */ |
2589 | char **pzErrmsg /* Error msg written here */ |
2590 | ); |
2591 | SQLITE_API void sqlite3_free_table(char **result); |
2592 | |
2593 | /* |
2594 | ** CAPI3REF: Formatted String Printing Functions |
2595 | ** |
2596 | ** These routines are work-alikes of the "printf()" family of functions |
2597 | ** from the standard C library. |
2598 | ** These routines understand most of the common formatting options from |
2599 | ** the standard library printf() |
2600 | ** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]). |
2601 | ** See the [built-in printf()] documentation for details. |
2602 | ** |
2603 | ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their |
2604 | ** results into memory obtained from [sqlite3_malloc64()]. |
2605 | ** The strings returned by these two routines should be |
2606 | ** released by [sqlite3_free()]. ^Both routines return a |
2607 | ** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough |
2608 | ** memory to hold the resulting string. |
2609 | ** |
2610 | ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from |
2611 | ** the standard C library. The result is written into the |
2612 | ** buffer supplied as the second parameter whose size is given by |
2613 | ** the first parameter. Note that the order of the |
2614 | ** first two parameters is reversed from snprintf().)^ This is an |
2615 | ** historical accident that cannot be fixed without breaking |
2616 | ** backwards compatibility. ^(Note also that sqlite3_snprintf() |
2617 | ** returns a pointer to its buffer instead of the number of |
2618 | ** characters actually written into the buffer.)^ We admit that |
2619 | ** the number of characters written would be a more useful return |
2620 | ** value but we cannot change the implementation of sqlite3_snprintf() |
2621 | ** now without breaking compatibility. |
2622 | ** |
2623 | ** ^As long as the buffer size is greater than zero, sqlite3_snprintf() |
2624 | ** guarantees that the buffer is always zero-terminated. ^The first |
2625 | ** parameter "n" is the total size of the buffer, including space for |
2626 | ** the zero terminator. So the longest string that can be completely |
2627 | ** written will be n-1 characters. |
2628 | ** |
2629 | ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf(). |
2630 | ** |
2631 | ** See also: [built-in printf()], [printf() SQL function] |
2632 | */ |
2633 | SQLITE_API char *sqlite3_mprintf(const char*,...); |
2634 | SQLITE_API char *sqlite3_vmprintf(const char*, va_list); |
2635 | SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...); |
2636 | SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list); |
2637 | |
2638 | /* |
2639 | ** CAPI3REF: Memory Allocation Subsystem |
2640 | ** |
2641 | ** The SQLite core uses these three routines for all of its own |
2642 | ** internal memory allocation needs. "Core" in the previous sentence |
2643 | ** does not include operating-system specific VFS implementation. The |
2644 | ** Windows VFS uses native malloc() and free() for some operations. |
2645 | ** |
2646 | ** ^The sqlite3_malloc() routine returns a pointer to a block |
2647 | ** of memory at least N bytes in length, where N is the parameter. |
2648 | ** ^If sqlite3_malloc() is unable to obtain sufficient free |
2649 | ** memory, it returns a NULL pointer. ^If the parameter N to |
2650 | ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns |
2651 | ** a NULL pointer. |
2652 | ** |
2653 | ** ^The sqlite3_malloc64(N) routine works just like |
2654 | ** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead |
2655 | ** of a signed 32-bit integer. |
2656 | ** |
2657 | ** ^Calling sqlite3_free() with a pointer previously returned |
2658 | ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so |
2659 | ** that it might be reused. ^The sqlite3_free() routine is |
2660 | ** a no-op if is called with a NULL pointer. Passing a NULL pointer |
2661 | ** to sqlite3_free() is harmless. After being freed, memory |
2662 | ** should neither be read nor written. Even reading previously freed |
2663 | ** memory might result in a segmentation fault or other severe error. |
2664 | ** Memory corruption, a segmentation fault, or other severe error |
2665 | ** might result if sqlite3_free() is called with a non-NULL pointer that |
2666 | ** was not obtained from sqlite3_malloc() or sqlite3_realloc(). |
2667 | ** |
2668 | ** ^The sqlite3_realloc(X,N) interface attempts to resize a |
2669 | ** prior memory allocation X to be at least N bytes. |
2670 | ** ^If the X parameter to sqlite3_realloc(X,N) |
2671 | ** is a NULL pointer then its behavior is identical to calling |
2672 | ** sqlite3_malloc(N). |
2673 | ** ^If the N parameter to sqlite3_realloc(X,N) is zero or |
2674 | ** negative then the behavior is exactly the same as calling |
2675 | ** sqlite3_free(X). |
2676 | ** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation |
2677 | ** of at least N bytes in size or NULL if insufficient memory is available. |
2678 | ** ^If M is the size of the prior allocation, then min(N,M) bytes |
2679 | ** of the prior allocation are copied into the beginning of buffer returned |
2680 | ** by sqlite3_realloc(X,N) and the prior allocation is freed. |
2681 | ** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the |
2682 | ** prior allocation is not freed. |
2683 | ** |
2684 | ** ^The sqlite3_realloc64(X,N) interfaces works the same as |
2685 | ** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead |
2686 | ** of a 32-bit signed integer. |
2687 | ** |
2688 | ** ^If X is a memory allocation previously obtained from sqlite3_malloc(), |
2689 | ** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then |
2690 | ** sqlite3_msize(X) returns the size of that memory allocation in bytes. |
2691 | ** ^The value returned by sqlite3_msize(X) might be larger than the number |
2692 | ** of bytes requested when X was allocated. ^If X is a NULL pointer then |
2693 | ** sqlite3_msize(X) returns zero. If X points to something that is not |
2694 | ** the beginning of memory allocation, or if it points to a formerly |
2695 | ** valid memory allocation that has now been freed, then the behavior |
2696 | ** of sqlite3_msize(X) is undefined and possibly harmful. |
2697 | ** |
2698 | ** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(), |
2699 | ** sqlite3_malloc64(), and sqlite3_realloc64() |
2700 | ** is always aligned to at least an 8 byte boundary, or to a |
2701 | ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time |
2702 | ** option is used. |
2703 | ** |
2704 | ** In SQLite version 3.5.0 and 3.5.1, it was possible to define |
2705 | ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in |
2706 | ** implementation of these routines to be omitted. That capability |
2707 | ** is no longer provided. Only built-in memory allocators can be used. |
2708 | ** |
2709 | ** Prior to SQLite version 3.7.10, the Windows OS interface layer called |
2710 | ** the system malloc() and free() directly when converting |
2711 | ** filenames between the UTF-8 encoding used by SQLite |
2712 | ** and whatever filename encoding is used by the particular Windows |
2713 | ** installation. Memory allocation errors were detected, but |
2714 | ** they were reported back as [SQLITE_CANTOPEN] or |
2715 | ** [SQLITE_IOERR] rather than [SQLITE_NOMEM]. |
2716 | ** |
2717 | ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] |
2718 | ** must be either NULL or else pointers obtained from a prior |
2719 | ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have |
2720 | ** not yet been released. |
2721 | ** |
2722 | ** The application must not read or write any part of |
2723 | ** a block of memory after it has been released using |
2724 | ** [sqlite3_free()] or [sqlite3_realloc()]. |
2725 | */ |
2726 | SQLITE_API void *sqlite3_malloc(int); |
2727 | SQLITE_API void *sqlite3_malloc64(sqlite3_uint64); |
2728 | SQLITE_API void *sqlite3_realloc(void*, int); |
2729 | SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64); |
2730 | SQLITE_API void sqlite3_free(void*); |
2731 | SQLITE_API sqlite3_uint64 sqlite3_msize(void*); |
2732 | |
2733 | /* |
2734 | ** CAPI3REF: Memory Allocator Statistics |
2735 | ** |
2736 | ** SQLite provides these two interfaces for reporting on the status |
2737 | ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] |
2738 | ** routines, which form the built-in memory allocation subsystem. |
2739 | ** |
2740 | ** ^The [sqlite3_memory_used()] routine returns the number of bytes |
2741 | ** of memory currently outstanding (malloced but not freed). |
2742 | ** ^The [sqlite3_memory_highwater()] routine returns the maximum |
2743 | ** value of [sqlite3_memory_used()] since the high-water mark |
2744 | ** was last reset. ^The values returned by [sqlite3_memory_used()] and |
2745 | ** [sqlite3_memory_highwater()] include any overhead |
2746 | ** added by SQLite in its implementation of [sqlite3_malloc()], |
2747 | ** but not overhead added by the any underlying system library |
2748 | ** routines that [sqlite3_malloc()] may call. |
2749 | ** |
2750 | ** ^The memory high-water mark is reset to the current value of |
2751 | ** [sqlite3_memory_used()] if and only if the parameter to |
2752 | ** [sqlite3_memory_highwater()] is true. ^The value returned |
2753 | ** by [sqlite3_memory_highwater(1)] is the high-water mark |
2754 | ** prior to the reset. |
2755 | */ |
2756 | SQLITE_API sqlite3_int64 sqlite3_memory_used(void); |
2757 | SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag); |
2758 | |
2759 | /* |
2760 | ** CAPI3REF: Pseudo-Random Number Generator |
2761 | ** |
2762 | ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to |
2763 | ** select random [ROWID | ROWIDs] when inserting new records into a table that |
2764 | ** already uses the largest possible [ROWID]. The PRNG is also used for |
2765 | ** the build-in random() and randomblob() SQL functions. This interface allows |
2766 | ** applications to access the same PRNG for other purposes. |
2767 | ** |
2768 | ** ^A call to this routine stores N bytes of randomness into buffer P. |
2769 | ** ^The P parameter can be a NULL pointer. |
2770 | ** |
2771 | ** ^If this routine has not been previously called or if the previous |
2772 | ** call had N less than one or a NULL pointer for P, then the PRNG is |
2773 | ** seeded using randomness obtained from the xRandomness method of |
2774 | ** the default [sqlite3_vfs] object. |
2775 | ** ^If the previous call to this routine had an N of 1 or more and a |
2776 | ** non-NULL P then the pseudo-randomness is generated |
2777 | ** internally and without recourse to the [sqlite3_vfs] xRandomness |
2778 | ** method. |
2779 | */ |
2780 | SQLITE_API void sqlite3_randomness(int N, void *P); |
2781 | |
2782 | /* |
2783 | ** CAPI3REF: Compile-Time Authorization Callbacks |
2784 | ** METHOD: sqlite3 |
2785 | ** KEYWORDS: {authorizer callback} |
2786 | ** |
2787 | ** ^This routine registers an authorizer callback with a particular |
2788 | ** [database connection], supplied in the first argument. |
2789 | ** ^The authorizer callback is invoked as SQL statements are being compiled |
2790 | ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], |
2791 | ** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()], |
2792 | ** and [sqlite3_prepare16_v3()]. ^At various |
2793 | ** points during the compilation process, as logic is being created |
2794 | ** to perform various actions, the authorizer callback is invoked to |
2795 | ** see if those actions are allowed. ^The authorizer callback should |
2796 | ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the |
2797 | ** specific action but allow the SQL statement to continue to be |
2798 | ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be |
2799 | ** rejected with an error. ^If the authorizer callback returns |
2800 | ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] |
2801 | ** then the [sqlite3_prepare_v2()] or equivalent call that triggered |
2802 | ** the authorizer will fail with an error message. |
2803 | ** |
2804 | ** When the callback returns [SQLITE_OK], that means the operation |
2805 | ** requested is ok. ^When the callback returns [SQLITE_DENY], the |
2806 | ** [sqlite3_prepare_v2()] or equivalent call that triggered the |
2807 | ** authorizer will fail with an error message explaining that |
2808 | ** access is denied. |
2809 | ** |
2810 | ** ^The first parameter to the authorizer callback is a copy of the third |
2811 | ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter |
2812 | ** to the callback is an integer [SQLITE_COPY | action code] that specifies |
2813 | ** the particular action to be authorized. ^The third through sixth parameters |
2814 | ** to the callback are either NULL pointers or zero-terminated strings |
2815 | ** that contain additional details about the action to be authorized. |
2816 | ** Applications must always be prepared to encounter a NULL pointer in any |
2817 | ** of the third through the sixth parameters of the authorization callback. |
2818 | ** |
2819 | ** ^If the action code is [SQLITE_READ] |
2820 | ** and the callback returns [SQLITE_IGNORE] then the |
2821 | ** [prepared statement] statement is constructed to substitute |
2822 | ** a NULL value in place of the table column that would have |
2823 | ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] |
2824 | ** return can be used to deny an untrusted user access to individual |
2825 | ** columns of a table. |
2826 | ** ^When a table is referenced by a [SELECT] but no column values are |
2827 | ** extracted from that table (for example in a query like |
2828 | ** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback |
2829 | ** is invoked once for that table with a column name that is an empty string. |
2830 | ** ^If the action code is [SQLITE_DELETE] and the callback returns |
2831 | ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the |
2832 | ** [truncate optimization] is disabled and all rows are deleted individually. |
2833 | ** |
2834 | ** An authorizer is used when [sqlite3_prepare | preparing] |
2835 | ** SQL statements from an untrusted source, to ensure that the SQL statements |
2836 | ** do not try to access data they are not allowed to see, or that they do not |
2837 | ** try to execute malicious statements that damage the database. For |
2838 | ** example, an application may allow a user to enter arbitrary |
2839 | ** SQL queries for evaluation by a database. But the application does |
2840 | ** not want the user to be able to make arbitrary changes to the |
2841 | ** database. An authorizer could then be put in place while the |
2842 | ** user-entered SQL is being [sqlite3_prepare | prepared] that |
2843 | ** disallows everything except [SELECT] statements. |
2844 | ** |
2845 | ** Applications that need to process SQL from untrusted sources |
2846 | ** might also consider lowering resource limits using [sqlite3_limit()] |
2847 | ** and limiting database size using the [max_page_count] [PRAGMA] |
2848 | ** in addition to using an authorizer. |
2849 | ** |
2850 | ** ^(Only a single authorizer can be in place on a database connection |
2851 | ** at a time. Each call to sqlite3_set_authorizer overrides the |
2852 | ** previous call.)^ ^Disable the authorizer by installing a NULL callback. |
2853 | ** The authorizer is disabled by default. |
2854 | ** |
2855 | ** The authorizer callback must not do anything that will modify |
2856 | ** the database connection that invoked the authorizer callback. |
2857 | ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their |
2858 | ** database connections for the meaning of "modify" in this paragraph. |
2859 | ** |
2860 | ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the |
2861 | ** statement might be re-prepared during [sqlite3_step()] due to a |
2862 | ** schema change. Hence, the application should ensure that the |
2863 | ** correct authorizer callback remains in place during the [sqlite3_step()]. |
2864 | ** |
2865 | ** ^Note that the authorizer callback is invoked only during |
2866 | ** [sqlite3_prepare()] or its variants. Authorization is not |
2867 | ** performed during statement evaluation in [sqlite3_step()], unless |
2868 | ** as stated in the previous paragraph, sqlite3_step() invokes |
2869 | ** sqlite3_prepare_v2() to reprepare a statement after a schema change. |
2870 | */ |
2871 | SQLITE_API int sqlite3_set_authorizer( |
2872 | sqlite3*, |
2873 | int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), |
2874 | void *pUserData |
2875 | ); |
2876 | |
2877 | /* |
2878 | ** CAPI3REF: Authorizer Return Codes |
2879 | ** |
2880 | ** The [sqlite3_set_authorizer | authorizer callback function] must |
2881 | ** return either [SQLITE_OK] or one of these two constants in order |
2882 | ** to signal SQLite whether or not the action is permitted. See the |
2883 | ** [sqlite3_set_authorizer | authorizer documentation] for additional |
2884 | ** information. |
2885 | ** |
2886 | ** Note that SQLITE_IGNORE is also used as a [conflict resolution mode] |
2887 | ** returned from the [sqlite3_vtab_on_conflict()] interface. |
2888 | */ |
2889 | #define SQLITE_DENY 1 /* Abort the SQL statement with an error */ |
2890 | #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ |
2891 | |
2892 | /* |
2893 | ** CAPI3REF: Authorizer Action Codes |
2894 | ** |
2895 | ** The [sqlite3_set_authorizer()] interface registers a callback function |
2896 | ** that is invoked to authorize certain SQL statement actions. The |
2897 | ** second parameter to the callback is an integer code that specifies |
2898 | ** what action is being authorized. These are the integer action codes that |
2899 | ** the authorizer callback may be passed. |
2900 | ** |
2901 | ** These action code values signify what kind of operation is to be |
2902 | ** authorized. The 3rd and 4th parameters to the authorization |
2903 | ** callback function will be parameters or NULL depending on which of these |
2904 | ** codes is used as the second parameter. ^(The 5th parameter to the |
2905 | ** authorizer callback is the name of the database ("main", "temp", |
2906 | ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback |
2907 | ** is the name of the inner-most trigger or view that is responsible for |
2908 | ** the access attempt or NULL if this access attempt is directly from |
2909 | ** top-level SQL code. |
2910 | */ |
2911 | /******************************************* 3rd ************ 4th ***********/ |
2912 | #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ |
2913 | #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ |
2914 | #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ |
2915 | #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ |
2916 | #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ |
2917 | #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ |
2918 | #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ |
2919 | #define SQLITE_CREATE_VIEW 8 /* View Name NULL */ |
2920 | #define SQLITE_DELETE 9 /* Table Name NULL */ |
2921 | #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ |
2922 | #define SQLITE_DROP_TABLE 11 /* Table Name NULL */ |
2923 | #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ |
2924 | #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ |
2925 | #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ |
2926 | #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ |
2927 | #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ |
2928 | #define SQLITE_DROP_VIEW 17 /* View Name NULL */ |
2929 | #define SQLITE_INSERT 18 /* Table Name NULL */ |
2930 | #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ |
2931 | #define SQLITE_READ 20 /* Table Name Column Name */ |
2932 | #define SQLITE_SELECT 21 /* NULL NULL */ |
2933 | #define SQLITE_TRANSACTION 22 /* Operation NULL */ |
2934 | #define SQLITE_UPDATE 23 /* Table Name Column Name */ |
2935 | #define SQLITE_ATTACH 24 /* Filename NULL */ |
2936 | #define SQLITE_DETACH 25 /* Database Name NULL */ |
2937 | #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ |
2938 | #define SQLITE_REINDEX 27 /* Index Name NULL */ |
2939 | #define SQLITE_ANALYZE 28 /* Table Name NULL */ |
2940 | #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ |
2941 | #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ |
2942 | #define SQLITE_FUNCTION 31 /* NULL Function Name */ |
2943 | #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ |
2944 | #define SQLITE_COPY 0 /* No longer used */ |
2945 | #define SQLITE_RECURSIVE 33 /* NULL NULL */ |
2946 | |
2947 | /* |
2948 | ** CAPI3REF: Tracing And Profiling Functions |
2949 | ** METHOD: sqlite3 |
2950 | ** |
2951 | ** These routines are deprecated. Use the [sqlite3_trace_v2()] interface |
2952 | ** instead of the routines described here. |
2953 | ** |
2954 | ** These routines register callback functions that can be used for |
2955 | ** tracing and profiling the execution of SQL statements. |
2956 | ** |
2957 | ** ^The callback function registered by sqlite3_trace() is invoked at |
2958 | ** various times when an SQL statement is being run by [sqlite3_step()]. |
2959 | ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the |
2960 | ** SQL statement text as the statement first begins executing. |
2961 | ** ^(Additional sqlite3_trace() callbacks might occur |
2962 | ** as each triggered subprogram is entered. The callbacks for triggers |
2963 | ** contain a UTF-8 SQL comment that identifies the trigger.)^ |
2964 | ** |
2965 | ** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit |
2966 | ** the length of [bound parameter] expansion in the output of sqlite3_trace(). |
2967 | ** |
2968 | ** ^The callback function registered by sqlite3_profile() is invoked |
2969 | ** as each SQL statement finishes. ^The profile callback contains |
2970 | ** the original statement text and an estimate of wall-clock time |
2971 | ** of how long that statement took to run. ^The profile callback |
2972 | ** time is in units of nanoseconds, however the current implementation |
2973 | ** is only capable of millisecond resolution so the six least significant |
2974 | ** digits in the time are meaningless. Future versions of SQLite |
2975 | ** might provide greater resolution on the profiler callback. The |
2976 | ** sqlite3_profile() function is considered experimental and is |
2977 | ** subject to change in future versions of SQLite. |
2978 | */ |
2979 | SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*, |
2980 | void(*xTrace)(void*,const char*), void*); |
2981 | SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*, |
2982 | void(*xProfile)(void*,const char*,sqlite3_uint64), void*); |
2983 | |
2984 | /* |
2985 | ** CAPI3REF: SQL Trace Event Codes |
2986 | ** KEYWORDS: SQLITE_TRACE |
2987 | ** |
2988 | ** These constants identify classes of events that can be monitored |
2989 | ** using the [sqlite3_trace_v2()] tracing logic. The M argument |
2990 | ** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of |
2991 | ** the following constants. ^The first argument to the trace callback |
2992 | ** is one of the following constants. |
2993 | ** |
2994 | ** New tracing constants may be added in future releases. |
2995 | ** |
2996 | ** ^A trace callback has four arguments: xCallback(T,C,P,X). |
2997 | ** ^The T argument is one of the integer type codes above. |
2998 | ** ^The C argument is a copy of the context pointer passed in as the |
2999 | ** fourth argument to [sqlite3_trace_v2()]. |
3000 | ** The P and X arguments are pointers whose meanings depend on T. |
3001 | ** |
3002 | ** <dl> |
3003 | ** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt> |
3004 | ** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement |
3005 | ** first begins running and possibly at other times during the |
3006 | ** execution of the prepared statement, such as at the start of each |
3007 | ** trigger subprogram. ^The P argument is a pointer to the |
3008 | ** [prepared statement]. ^The X argument is a pointer to a string which |
3009 | ** is the unexpanded SQL text of the prepared statement or an SQL comment |
3010 | ** that indicates the invocation of a trigger. ^The callback can compute |
3011 | ** the same text that would have been returned by the legacy [sqlite3_trace()] |
3012 | ** interface by using the X argument when X begins with "--" and invoking |
3013 | ** [sqlite3_expanded_sql(P)] otherwise. |
3014 | ** |
3015 | ** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt> |
3016 | ** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same |
3017 | ** information as is provided by the [sqlite3_profile()] callback. |
3018 | ** ^The P argument is a pointer to the [prepared statement] and the |
3019 | ** X argument points to a 64-bit integer which is the estimated of |
3020 | ** the number of nanosecond that the prepared statement took to run. |
3021 | ** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes. |
3022 | ** |
3023 | ** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt> |
3024 | ** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared |
3025 | ** statement generates a single row of result. |
3026 | ** ^The P argument is a pointer to the [prepared statement] and the |
3027 | ** X argument is unused. |
3028 | ** |
3029 | ** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt> |
3030 | ** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database |
3031 | ** connection closes. |
3032 | ** ^The P argument is a pointer to the [database connection] object |
3033 | ** and the X argument is unused. |
3034 | ** </dl> |
3035 | */ |
3036 | #define SQLITE_TRACE_STMT 0x01 |
3037 | #define SQLITE_TRACE_PROFILE 0x02 |
3038 | #define SQLITE_TRACE_ROW 0x04 |
3039 | #define SQLITE_TRACE_CLOSE 0x08 |
3040 | |
3041 | /* |
3042 | ** CAPI3REF: SQL Trace Hook |
3043 | ** METHOD: sqlite3 |
3044 | ** |
3045 | ** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback |
3046 | ** function X against [database connection] D, using property mask M |
3047 | ** and context pointer P. ^If the X callback is |
3048 | ** NULL or if the M mask is zero, then tracing is disabled. The |
3049 | ** M argument should be the bitwise OR-ed combination of |
3050 | ** zero or more [SQLITE_TRACE] constants. |
3051 | ** |
3052 | ** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides |
3053 | ** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2(). |
3054 | ** |
3055 | ** ^The X callback is invoked whenever any of the events identified by |
3056 | ** mask M occur. ^The integer return value from the callback is currently |
3057 | ** ignored, though this may change in future releases. Callback |
3058 | ** implementations should return zero to ensure future compatibility. |
3059 | ** |
3060 | ** ^A trace callback is invoked with four arguments: callback(T,C,P,X). |
3061 | ** ^The T argument is one of the [SQLITE_TRACE] |
3062 | ** constants to indicate why the callback was invoked. |
3063 | ** ^The C argument is a copy of the context pointer. |
3064 | ** The P and X arguments are pointers whose meanings depend on T. |
3065 | ** |
3066 | ** The sqlite3_trace_v2() interface is intended to replace the legacy |
3067 | ** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which |
3068 | ** are deprecated. |
3069 | */ |
3070 | SQLITE_API int sqlite3_trace_v2( |
3071 | sqlite3*, |
3072 | unsigned uMask, |
3073 | int(*xCallback)(unsigned,void*,void*,void*), |
3074 | void *pCtx |
3075 | ); |
3076 | |
3077 | /* |
3078 | ** CAPI3REF: Query Progress Callbacks |
3079 | ** METHOD: sqlite3 |
3080 | ** |
3081 | ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback |
3082 | ** function X to be invoked periodically during long running calls to |
3083 | ** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for |
3084 | ** database connection D. An example use for this |
3085 | ** interface is to keep a GUI updated during a large query. |
3086 | ** |
3087 | ** ^The parameter P is passed through as the only parameter to the |
3088 | ** callback function X. ^The parameter N is the approximate number of |
3089 | ** [virtual machine instructions] that are evaluated between successive |
3090 | ** invocations of the callback X. ^If N is less than one then the progress |
3091 | ** handler is disabled. |
3092 | ** |
3093 | ** ^Only a single progress handler may be defined at one time per |
3094 | ** [database connection]; setting a new progress handler cancels the |
3095 | ** old one. ^Setting parameter X to NULL disables the progress handler. |
3096 | ** ^The progress handler is also disabled by setting N to a value less |
3097 | ** than 1. |
3098 | ** |
3099 | ** ^If the progress callback returns non-zero, the operation is |
3100 | ** interrupted. This feature can be used to implement a |
3101 | ** "Cancel" button on a GUI progress dialog box. |
3102 | ** |
3103 | ** The progress handler callback must not do anything that will modify |
3104 | ** the database connection that invoked the progress handler. |
3105 | ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their |
3106 | ** database connections for the meaning of "modify" in this paragraph. |
3107 | ** |
3108 | */ |
3109 | SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); |
3110 | |
3111 | /* |
3112 | ** CAPI3REF: Opening A New Database Connection |
3113 | ** CONSTRUCTOR: sqlite3 |
3114 | ** |
3115 | ** ^These routines open an SQLite database file as specified by the |
3116 | ** filename argument. ^The filename argument is interpreted as UTF-8 for |
3117 | ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte |
3118 | ** order for sqlite3_open16(). ^(A [database connection] handle is usually |
3119 | ** returned in *ppDb, even if an error occurs. The only exception is that |
3120 | ** if SQLite is unable to allocate memory to hold the [sqlite3] object, |
3121 | ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] |
3122 | ** object.)^ ^(If the database is opened (and/or created) successfully, then |
3123 | ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The |
3124 | ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain |
3125 | ** an English language description of the error following a failure of any |
3126 | ** of the sqlite3_open() routines. |
3127 | ** |
3128 | ** ^The default encoding will be UTF-8 for databases created using |
3129 | ** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases |
3130 | ** created using sqlite3_open16() will be UTF-16 in the native byte order. |
3131 | ** |
3132 | ** Whether or not an error occurs when it is opened, resources |
3133 | ** associated with the [database connection] handle should be released by |
3134 | ** passing it to [sqlite3_close()] when it is no longer required. |
3135 | ** |
3136 | ** The sqlite3_open_v2() interface works like sqlite3_open() |
3137 | ** except that it accepts two additional parameters for additional control |
3138 | ** over the new database connection. ^(The flags parameter to |
3139 | ** sqlite3_open_v2() can take one of |
3140 | ** the following three values, optionally combined with the |
3141 | ** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE], |
3142 | ** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^ |
3143 | ** |
3144 | ** <dl> |
3145 | ** ^(<dt>[SQLITE_OPEN_READONLY]</dt> |
3146 | ** <dd>The database is opened in read-only mode. If the database does not |
3147 | ** already exist, an error is returned.</dd>)^ |
3148 | ** |
3149 | ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt> |
3150 | ** <dd>The database is opened for reading and writing if possible, or reading |
3151 | ** only if the file is write protected by the operating system. In either |
3152 | ** case the database must already exist, otherwise an error is returned.</dd>)^ |
3153 | ** |
3154 | ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt> |
3155 | ** <dd>The database is opened for reading and writing, and is created if |
3156 | ** it does not already exist. This is the behavior that is always used for |
3157 | ** sqlite3_open() and sqlite3_open16().</dd>)^ |
3158 | ** </dl> |
3159 | ** |
3160 | ** If the 3rd parameter to sqlite3_open_v2() is not one of the |
3161 | ** combinations shown above optionally combined with other |
3162 | ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] |
3163 | ** then the behavior is undefined. |
3164 | ** |
3165 | ** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection |
3166 | ** opens in the multi-thread [threading mode] as long as the single-thread |
3167 | ** mode has not been set at compile-time or start-time. ^If the |
3168 | ** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens |
3169 | ** in the serialized [threading mode] unless single-thread was |
3170 | ** previously selected at compile-time or start-time. |
3171 | ** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be |
3172 | ** eligible to use [shared cache mode], regardless of whether or not shared |
3173 | ** cache is enabled using [sqlite3_enable_shared_cache()]. ^The |
3174 | ** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not |
3175 | ** participate in [shared cache mode] even if it is enabled. |
3176 | ** |
3177 | ** ^The fourth parameter to sqlite3_open_v2() is the name of the |
3178 | ** [sqlite3_vfs] object that defines the operating system interface that |
3179 | ** the new database connection should use. ^If the fourth parameter is |
3180 | ** a NULL pointer then the default [sqlite3_vfs] object is used. |
3181 | ** |
3182 | ** ^If the filename is ":memory:", then a private, temporary in-memory database |
3183 | ** is created for the connection. ^This in-memory database will vanish when |
3184 | ** the database connection is closed. Future versions of SQLite might |
3185 | ** make use of additional special filenames that begin with the ":" character. |
3186 | ** It is recommended that when a database filename actually does begin with |
3187 | ** a ":" character you should prefix the filename with a pathname such as |
3188 | ** "./" to avoid ambiguity. |
3189 | ** |
3190 | ** ^If the filename is an empty string, then a private, temporary |
3191 | ** on-disk database will be created. ^This private database will be |
3192 | ** automatically deleted as soon as the database connection is closed. |
3193 | ** |
3194 | ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3> |
3195 | ** |
3196 | ** ^If [URI filename] interpretation is enabled, and the filename argument |
3197 | ** begins with "file:", then the filename is interpreted as a URI. ^URI |
3198 | ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is |
3199 | ** set in the third argument to sqlite3_open_v2(), or if it has |
3200 | ** been enabled globally using the [SQLITE_CONFIG_URI] option with the |
3201 | ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option. |
3202 | ** URI filename interpretation is turned off |
3203 | ** by default, but future releases of SQLite might enable URI filename |
3204 | ** interpretation by default. See "[URI filenames]" for additional |
3205 | ** information. |
3206 | ** |
3207 | ** URI filenames are parsed according to RFC 3986. ^If the URI contains an |
3208 | ** authority, then it must be either an empty string or the string |
3209 | ** "localhost". ^If the authority is not an empty string or "localhost", an |
3210 | ** error is returned to the caller. ^The fragment component of a URI, if |
3211 | ** present, is ignored. |
3212 | ** |
3213 | ** ^SQLite uses the path component of the URI as the name of the disk file |
3214 | ** which contains the database. ^If the path begins with a '/' character, |
3215 | ** then it is interpreted as an absolute path. ^If the path does not begin |
3216 | ** with a '/' (meaning that the authority section is omitted from the URI) |
3217 | ** then the path is interpreted as a relative path. |
3218 | ** ^(On windows, the first component of an absolute path |
3219 | ** is a drive specification (e.g. "C:").)^ |
3220 | ** |
3221 | ** [[core URI query parameters]] |
3222 | ** The query component of a URI may contain parameters that are interpreted |
3223 | ** either by SQLite itself, or by a [VFS | custom VFS implementation]. |
3224 | ** SQLite and its built-in [VFSes] interpret the |
3225 | ** following query parameters: |
3226 | ** |
3227 | ** <ul> |
3228 | ** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of |
3229 | ** a VFS object that provides the operating system interface that should |
3230 | ** be used to access the database file on disk. ^If this option is set to |
3231 | ** an empty string the default VFS object is used. ^Specifying an unknown |
3232 | ** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is |
3233 | ** present, then the VFS specified by the option takes precedence over |
3234 | ** the value passed as the fourth parameter to sqlite3_open_v2(). |
3235 | ** |
3236 | ** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw", |
3237 | ** "rwc", or "memory". Attempting to set it to any other value is |
3238 | ** an error)^. |
3239 | ** ^If "ro" is specified, then the database is opened for read-only |
3240 | ** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the |
3241 | ** third argument to sqlite3_open_v2(). ^If the mode option is set to |
3242 | ** "rw", then the database is opened for read-write (but not create) |
3243 | ** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had |
3244 | ** been set. ^Value "rwc" is equivalent to setting both |
3245 | ** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is |
3246 | ** set to "memory" then a pure [in-memory database] that never reads |
3247 | ** or writes from disk is used. ^It is an error to specify a value for |
3248 | ** the mode parameter that is less restrictive than that specified by |
3249 | ** the flags passed in the third parameter to sqlite3_open_v2(). |
3250 | ** |
3251 | ** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or |
3252 | ** "private". ^Setting it to "shared" is equivalent to setting the |
3253 | ** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to |
3254 | ** sqlite3_open_v2(). ^Setting the cache parameter to "private" is |
3255 | ** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit. |
3256 | ** ^If sqlite3_open_v2() is used and the "cache" parameter is present in |
3257 | ** a URI filename, its value overrides any behavior requested by setting |
3258 | ** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag. |
3259 | ** |
3260 | ** <li> <b>psow</b>: ^The psow parameter indicates whether or not the |
3261 | ** [powersafe overwrite] property does or does not apply to the |
3262 | ** storage media on which the database file resides. |
3263 | ** |
3264 | ** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter |
3265 | ** which if set disables file locking in rollback journal modes. This |
3266 | ** is useful for accessing a database on a filesystem that does not |
3267 | ** support locking. Caution: Database corruption might result if two |
3268 | ** or more processes write to the same database and any one of those |
3269 | ** processes uses nolock=1. |
3270 | ** |
3271 | ** <li> <b>immutable</b>: ^The immutable parameter is a boolean query |
3272 | ** parameter that indicates that the database file is stored on |
3273 | ** read-only media. ^When immutable is set, SQLite assumes that the |
3274 | ** database file cannot be changed, even by a process with higher |
3275 | ** privilege, and so the database is opened read-only and all locking |
3276 | ** and change detection is disabled. Caution: Setting the immutable |
3277 | ** property on a database file that does in fact change can result |
3278 | ** in incorrect query results and/or [SQLITE_CORRUPT] errors. |
3279 | ** See also: [SQLITE_IOCAP_IMMUTABLE]. |
3280 | ** |
3281 | ** </ul> |
3282 | ** |
3283 | ** ^Specifying an unknown parameter in the query component of a URI is not an |
3284 | ** error. Future versions of SQLite might understand additional query |
3285 | ** parameters. See "[query parameters with special meaning to SQLite]" for |
3286 | ** additional information. |
3287 | ** |
3288 | ** [[URI filename examples]] <h3>URI filename examples</h3> |
3289 | ** |
3290 | ** <table border="1" align=center cellpadding=5> |
3291 | ** <tr><th> URI filenames <th> Results |
3292 | ** <tr><td> file:data.db <td> |
3293 | ** Open the file "data.db" in the current directory. |
3294 | ** <tr><td> file:/home/fred/data.db<br> |
3295 | ** file:///home/fred/data.db <br> |
3296 | ** file://localhost/home/fred/data.db <br> <td> |
3297 | ** Open the database file "/home/fred/data.db". |
3298 | ** <tr><td> file://darkstar/home/fred/data.db <td> |
3299 | ** An error. "darkstar" is not a recognized authority. |
3300 | ** <tr><td style="white-space:nowrap"> |
3301 | ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db |
3302 | ** <td> Windows only: Open the file "data.db" on fred's desktop on drive |
3303 | ** C:. Note that the %20 escaping in this example is not strictly |
3304 | ** necessary - space characters can be used literally |
3305 | ** in URI filenames. |
3306 | ** <tr><td> file:data.db?mode=ro&cache=private <td> |
3307 | ** Open file "data.db" in the current directory for read-only access. |
3308 | ** Regardless of whether or not shared-cache mode is enabled by |
3309 | ** default, use a private cache. |
3310 | ** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td> |
3311 | ** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile" |
3312 | ** that uses dot-files in place of posix advisory locking. |
3313 | ** <tr><td> file:data.db?mode=readonly <td> |
3314 | ** An error. "readonly" is not a valid option for the "mode" parameter. |
3315 | ** </table> |
3316 | ** |
3317 | ** ^URI hexadecimal escape sequences (%HH) are supported within the path and |
3318 | ** query components of a URI. A hexadecimal escape sequence consists of a |
3319 | ** percent sign - "%" - followed by exactly two hexadecimal digits |
3320 | ** specifying an octet value. ^Before the path or query components of a |
3321 | ** URI filename are interpreted, they are encoded using UTF-8 and all |
3322 | ** hexadecimal escape sequences replaced by a single byte containing the |
3323 | ** corresponding octet. If this process generates an invalid UTF-8 encoding, |
3324 | ** the results are undefined. |
3325 | ** |
3326 | ** <b>Note to Windows users:</b> The encoding used for the filename argument |
3327 | ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever |
3328 | ** codepage is currently defined. Filenames containing international |
3329 | ** characters must be converted to UTF-8 prior to passing them into |
3330 | ** sqlite3_open() or sqlite3_open_v2(). |
3331 | ** |
3332 | ** <b>Note to Windows Runtime users:</b> The temporary directory must be set |
3333 | ** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various |
3334 | ** features that require the use of temporary files may fail. |
3335 | ** |
3336 | ** See also: [sqlite3_temp_directory] |
3337 | */ |
3338 | SQLITE_API int sqlite3_open( |
3339 | const char *filename, /* Database filename (UTF-8) */ |
3340 | sqlite3 **ppDb /* OUT: SQLite db handle */ |
3341 | ); |
3342 | SQLITE_API int sqlite3_open16( |
3343 | const void *filename, /* Database filename (UTF-16) */ |
3344 | sqlite3 **ppDb /* OUT: SQLite db handle */ |
3345 | ); |
3346 | SQLITE_API int sqlite3_open_v2( |
3347 | const char *filename, /* Database filename (UTF-8) */ |
3348 | sqlite3 **ppDb, /* OUT: SQLite db handle */ |
3349 | int flags, /* Flags */ |
3350 | const char *zVfs /* Name of VFS module to use */ |
3351 | ); |
3352 | |
3353 | /* |
3354 | ** CAPI3REF: Obtain Values For URI Parameters |
3355 | ** |
3356 | ** These are utility routines, useful to VFS implementations, that check |
3357 | ** to see if a database file was a URI that contained a specific query |
3358 | ** parameter, and if so obtains the value of that query parameter. |
3359 | ** |
3360 | ** If F is the database filename pointer passed into the xOpen() method of |
3361 | ** a VFS implementation when the flags parameter to xOpen() has one or |
3362 | ** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and |
3363 | ** P is the name of the query parameter, then |
3364 | ** sqlite3_uri_parameter(F,P) returns the value of the P |
3365 | ** parameter if it exists or a NULL pointer if P does not appear as a |
3366 | ** query parameter on F. If P is a query parameter of F |
3367 | ** has no explicit value, then sqlite3_uri_parameter(F,P) returns |
3368 | ** a pointer to an empty string. |
3369 | ** |
3370 | ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean |
3371 | ** parameter and returns true (1) or false (0) according to the value |
3372 | ** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the |
3373 | ** value of query parameter P is one of "yes", "true", or "on" in any |
3374 | ** case or if the value begins with a non-zero number. The |
3375 | ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of |
3376 | ** query parameter P is one of "no", "false", or "off" in any case or |
3377 | ** if the value begins with a numeric zero. If P is not a query |
3378 | ** parameter on F or if the value of P is does not match any of the |
3379 | ** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0). |
3380 | ** |
3381 | ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a |
3382 | ** 64-bit signed integer and returns that integer, or D if P does not |
3383 | ** exist. If the value of P is something other than an integer, then |
3384 | ** zero is returned. |
3385 | ** |
3386 | ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and |
3387 | ** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and |
3388 | ** is not a database file pathname pointer that SQLite passed into the xOpen |
3389 | ** VFS method, then the behavior of this routine is undefined and probably |
3390 | ** undesirable. |
3391 | */ |
3392 | SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam); |
3393 | SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault); |
3394 | SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64); |
3395 | |
3396 | |
3397 | /* |
3398 | ** CAPI3REF: Error Codes And Messages |
3399 | ** METHOD: sqlite3 |
3400 | ** |
3401 | ** ^If the most recent sqlite3_* API call associated with |
3402 | ** [database connection] D failed, then the sqlite3_errcode(D) interface |
3403 | ** returns the numeric [result code] or [extended result code] for that |
3404 | ** API call. |
3405 | ** ^The sqlite3_extended_errcode() |
3406 | ** interface is the same except that it always returns the |
3407 | ** [extended result code] even when extended result codes are |
3408 | ** disabled. |
3409 | ** |
3410 | ** The values returned by sqlite3_errcode() and/or |
3411 | ** sqlite3_extended_errcode() might change with each API call. |
3412 | ** Except, there are some interfaces that are guaranteed to never |
3413 | ** change the value of the error code. The error-code preserving |
3414 | ** interfaces are: |
3415 | ** |
3416 | ** <ul> |
3417 | ** <li> sqlite3_errcode() |
3418 | ** <li> sqlite3_extended_errcode() |
3419 | ** <li> sqlite3_errmsg() |
3420 | ** <li> sqlite3_errmsg16() |
3421 | ** </ul> |
3422 | ** |
3423 | ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language |
3424 | ** text that describes the error, as either UTF-8 or UTF-16 respectively. |
3425 | ** ^(Memory to hold the error message string is managed internally. |
3426 | ** The application does not need to worry about freeing the result. |
3427 | ** However, the error string might be overwritten or deallocated by |
3428 | ** subsequent calls to other SQLite interface functions.)^ |
3429 | ** |
3430 | ** ^The sqlite3_errstr() interface returns the English-language text |
3431 | ** that describes the [result code], as UTF-8. |
3432 | ** ^(Memory to hold the error message string is managed internally |
3433 | ** and must not be freed by the application)^. |
3434 | ** |
3435 | ** When the serialized [threading mode] is in use, it might be the |
3436 | ** case that a second error occurs on a separate thread in between |
3437 | ** the time of the first error and the call to these interfaces. |
3438 | ** When that happens, the second error will be reported since these |
3439 | ** interfaces always report the most recent result. To avoid |
3440 | ** this, each thread can obtain exclusive use of the [database connection] D |
3441 | ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning |
3442 | ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after |
3443 | ** all calls to the interfaces listed here are completed. |
3444 | ** |
3445 | ** If an interface fails with SQLITE_MISUSE, that means the interface |
3446 | ** was invoked incorrectly by the application. In that case, the |
3447 | ** error code and message may or may not be set. |
3448 | */ |
3449 | SQLITE_API int sqlite3_errcode(sqlite3 *db); |
3450 | SQLITE_API int sqlite3_extended_errcode(sqlite3 *db); |
3451 | SQLITE_API const char *sqlite3_errmsg(sqlite3*); |
3452 | SQLITE_API const void *sqlite3_errmsg16(sqlite3*); |
3453 | SQLITE_API const char *sqlite3_errstr(int); |
3454 | |
3455 | /* |
3456 | ** CAPI3REF: Prepared Statement Object |
3457 | ** KEYWORDS: {prepared statement} {prepared statements} |
3458 | ** |
3459 | ** An instance of this object represents a single SQL statement that |
3460 | ** has been compiled into binary form and is ready to be evaluated. |
3461 | ** |
3462 | ** Think of each SQL statement as a separate computer program. The |
3463 | ** original SQL text is source code. A prepared statement object |
3464 | ** is the compiled object code. All SQL must be converted into a |
3465 | ** prepared statement before it can be run. |
3466 | ** |
3467 | ** The life-cycle of a prepared statement object usually goes like this: |
3468 | ** |
3469 | ** <ol> |
3470 | ** <li> Create the prepared statement object using [sqlite3_prepare_v2()]. |
3471 | ** <li> Bind values to [parameters] using the sqlite3_bind_*() |
3472 | ** interfaces. |
3473 | ** <li> Run the SQL by calling [sqlite3_step()] one or more times. |
3474 | ** <li> Reset the prepared statement using [sqlite3_reset()] then go back |
3475 | ** to step 2. Do this zero or more times. |
3476 | ** <li> Destroy the object using [sqlite3_finalize()]. |
3477 | ** </ol> |
3478 | */ |
3479 | typedef struct sqlite3_stmt sqlite3_stmt; |
3480 | |
3481 | /* |
3482 | ** CAPI3REF: Run-time Limits |
3483 | ** METHOD: sqlite3 |
3484 | ** |
3485 | ** ^(This interface allows the size of various constructs to be limited |
3486 | ** on a connection by connection basis. The first parameter is the |
3487 | ** [database connection] whose limit is to be set or queried. The |
3488 | ** second parameter is one of the [limit categories] that define a |
3489 | ** class of constructs to be size limited. The third parameter is the |
3490 | ** new limit for that construct.)^ |
3491 | ** |
3492 | ** ^If the new limit is a negative number, the limit is unchanged. |
3493 | ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a |
3494 | ** [limits | hard upper bound] |
3495 | ** set at compile-time by a C preprocessor macro called |
3496 | ** [limits | SQLITE_MAX_<i>NAME</i>]. |
3497 | ** (The "_LIMIT_" in the name is changed to "_MAX_".))^ |
3498 | ** ^Attempts to increase a limit above its hard upper bound are |
3499 | ** silently truncated to the hard upper bound. |
3500 | ** |
3501 | ** ^Regardless of whether or not the limit was changed, the |
3502 | ** [sqlite3_limit()] interface returns the prior value of the limit. |
3503 | ** ^Hence, to find the current value of a limit without changing it, |
3504 | ** simply invoke this interface with the third parameter set to -1. |
3505 | ** |
3506 | ** Run-time limits are intended for use in applications that manage |
3507 | ** both their own internal database and also databases that are controlled |
3508 | ** by untrusted external sources. An example application might be a |
3509 | ** web browser that has its own databases for storing history and |
3510 | ** separate databases controlled by JavaScript applications downloaded |
3511 | ** off the Internet. The internal databases can be given the |
3512 | ** large, default limits. Databases managed by external sources can |
3513 | ** be given much smaller limits designed to prevent a denial of service |
3514 | ** attack. Developers might also want to use the [sqlite3_set_authorizer()] |
3515 | ** interface to further control untrusted SQL. The size of the database |
3516 | ** created by an untrusted script can be contained using the |
3517 | ** [max_page_count] [PRAGMA]. |
3518 | ** |
3519 | ** New run-time limit categories may be added in future releases. |
3520 | */ |
3521 | SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal); |
3522 | |
3523 | /* |
3524 | ** CAPI3REF: Run-Time Limit Categories |
3525 | ** KEYWORDS: {limit category} {*limit categories} |
3526 | ** |
3527 | ** These constants define various performance limits |
3528 | ** that can be lowered at run-time using [sqlite3_limit()]. |
3529 | ** The synopsis of the meanings of the various limits is shown below. |
3530 | ** Additional information is available at [limits | Limits in SQLite]. |
3531 | ** |
3532 | ** <dl> |
3533 | ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt> |
3534 | ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^ |
3535 | ** |
3536 | ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt> |
3537 | ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^ |
3538 | ** |
3539 | ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt> |
3540 | ** <dd>The maximum number of columns in a table definition or in the |
3541 | ** result set of a [SELECT] or the maximum number of columns in an index |
3542 | ** or in an ORDER BY or GROUP BY clause.</dd>)^ |
3543 | ** |
3544 | ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt> |
3545 | ** <dd>The maximum depth of the parse tree on any expression.</dd>)^ |
3546 | ** |
3547 | ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt> |
3548 | ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^ |
3549 | ** |
3550 | ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt> |
3551 | ** <dd>The maximum number of instructions in a virtual machine program |
3552 | ** used to implement an SQL statement. If [sqlite3_prepare_v2()] or |
3553 | ** the equivalent tries to allocate space for more than this many opcodes |
3554 | ** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^ |
3555 | ** |
3556 | ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt> |
3557 | ** <dd>The maximum number of arguments on a function.</dd>)^ |
3558 | ** |
3559 | ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt> |
3560 | ** <dd>The maximum number of [ATTACH | attached databases].)^</dd> |
3561 | ** |
3562 | ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] |
3563 | ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt> |
3564 | ** <dd>The maximum length of the pattern argument to the [LIKE] or |
3565 | ** [GLOB] operators.</dd>)^ |
3566 | ** |
3567 | ** [[SQLITE_LIMIT_VARIABLE_NUMBER]] |
3568 | ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt> |
3569 | ** <dd>The maximum index number of any [parameter] in an SQL statement.)^ |
3570 | ** |
3571 | ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt> |
3572 | ** <dd>The maximum depth of recursion for triggers.</dd>)^ |
3573 | ** |
3574 | ** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt> |
3575 | ** <dd>The maximum number of auxiliary worker threads that a single |
3576 | ** [prepared statement] may start.</dd>)^ |
3577 | ** </dl> |
3578 | */ |
3579 | #define SQLITE_LIMIT_LENGTH 0 |
3580 | #define SQLITE_LIMIT_SQL_LENGTH 1 |
3581 | #define SQLITE_LIMIT_COLUMN 2 |
3582 | #define SQLITE_LIMIT_EXPR_DEPTH 3 |
3583 | #define SQLITE_LIMIT_COMPOUND_SELECT 4 |
3584 | #define SQLITE_LIMIT_VDBE_OP 5 |
3585 | #define SQLITE_LIMIT_FUNCTION_ARG 6 |
3586 | #define SQLITE_LIMIT_ATTACHED 7 |
3587 | #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 |
3588 | #define SQLITE_LIMIT_VARIABLE_NUMBER 9 |
3589 | #define SQLITE_LIMIT_TRIGGER_DEPTH 10 |
3590 | #define SQLITE_LIMIT_WORKER_THREADS 11 |
3591 | |
3592 | /* |
3593 | ** CAPI3REF: Prepare Flags |
3594 | ** |
3595 | ** These constants define various flags that can be passed into |
3596 | ** "prepFlags" parameter of the [sqlite3_prepare_v3()] and |
3597 | ** [sqlite3_prepare16_v3()] interfaces. |
3598 | ** |
3599 | ** New flags may be added in future releases of SQLite. |
3600 | ** |
3601 | ** <dl> |
3602 | ** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt> |
3603 | ** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner |
3604 | ** that the prepared statement will be retained for a long time and |
3605 | ** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()] |
3606 | ** and [sqlite3_prepare16_v3()] assume that the prepared statement will |
3607 | ** be used just once or at most a few times and then destroyed using |
3608 | ** [sqlite3_finalize()] relatively soon. The current implementation acts |
3609 | ** on this hint by avoiding the use of [lookaside memory] so as not to |
3610 | ** deplete the limited store of lookaside memory. Future versions of |
3611 | ** SQLite may act on this hint differently. |
3612 | ** </dl> |
3613 | */ |
3614 | #define SQLITE_PREPARE_PERSISTENT 0x01 |
3615 | |
3616 | /* |
3617 | ** CAPI3REF: Compiling An SQL Statement |
3618 | ** KEYWORDS: {SQL statement compiler} |
3619 | ** METHOD: sqlite3 |
3620 | ** CONSTRUCTOR: sqlite3_stmt |
3621 | ** |
3622 | ** To execute an SQL statement, it must first be compiled into a byte-code |
3623 | ** program using one of these routines. Or, in other words, these routines |
3624 | ** are constructors for the [prepared statement] object. |
3625 | ** |
3626 | ** The preferred routine to use is [sqlite3_prepare_v2()]. The |
3627 | ** [sqlite3_prepare()] interface is legacy and should be avoided. |
3628 | ** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used |
3629 | ** for special purposes. |
3630 | ** |
3631 | ** The use of the UTF-8 interfaces is preferred, as SQLite currently |
3632 | ** does all parsing using UTF-8. The UTF-16 interfaces are provided |
3633 | ** as a convenience. The UTF-16 interfaces work by converting the |
3634 | ** input text into UTF-8, then invoking the corresponding UTF-8 interface. |
3635 | ** |
3636 | ** The first argument, "db", is a [database connection] obtained from a |
3637 | ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or |
3638 | ** [sqlite3_open16()]. The database connection must not have been closed. |
3639 | ** |
3640 | ** The second argument, "zSql", is the statement to be compiled, encoded |
3641 | ** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(), |
3642 | ** and sqlite3_prepare_v3() |
3643 | ** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(), |
3644 | ** and sqlite3_prepare16_v3() use UTF-16. |
3645 | ** |
3646 | ** ^If the nByte argument is negative, then zSql is read up to the |
3647 | ** first zero terminator. ^If nByte is positive, then it is the |
3648 | ** number of bytes read from zSql. ^If nByte is zero, then no prepared |
3649 | ** statement is generated. |
3650 | ** If the caller knows that the supplied string is nul-terminated, then |
3651 | ** there is a small performance advantage to passing an nByte parameter that |
3652 | ** is the number of bytes in the input string <i>including</i> |
3653 | ** the nul-terminator. |
3654 | ** |
3655 | ** ^If pzTail is not NULL then *pzTail is made to point to the first byte |
3656 | ** past the end of the first SQL statement in zSql. These routines only |
3657 | ** compile the first statement in zSql, so *pzTail is left pointing to |
3658 | ** what remains uncompiled. |
3659 | ** |
3660 | ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be |
3661 | ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set |
3662 | ** to NULL. ^If the input text contains no SQL (if the input is an empty |
3663 | ** string or a comment) then *ppStmt is set to NULL. |
3664 | ** The calling procedure is responsible for deleting the compiled |
3665 | ** SQL statement using [sqlite3_finalize()] after it has finished with it. |
3666 | ** ppStmt may not be NULL. |
3667 | ** |
3668 | ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK]; |
3669 | ** otherwise an [error code] is returned. |
3670 | ** |
3671 | ** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(), |
3672 | ** and sqlite3_prepare16_v3() interfaces are recommended for all new programs. |
3673 | ** The older interfaces (sqlite3_prepare() and sqlite3_prepare16()) |
3674 | ** are retained for backwards compatibility, but their use is discouraged. |
3675 | ** ^In the "vX" interfaces, the prepared statement |
3676 | ** that is returned (the [sqlite3_stmt] object) contains a copy of the |
3677 | ** original SQL text. This causes the [sqlite3_step()] interface to |
3678 | ** behave differently in three ways: |
3679 | ** |
3680 | ** <ol> |
3681 | ** <li> |
3682 | ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it |
3683 | ** always used to do, [sqlite3_step()] will automatically recompile the SQL |
3684 | ** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY] |
3685 | ** retries will occur before sqlite3_step() gives up and returns an error. |
3686 | ** </li> |
3687 | ** |
3688 | ** <li> |
3689 | ** ^When an error occurs, [sqlite3_step()] will return one of the detailed |
3690 | ** [error codes] or [extended error codes]. ^The legacy behavior was that |
3691 | ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code |
3692 | ** and the application would have to make a second call to [sqlite3_reset()] |
3693 | ** in order to find the underlying cause of the problem. With the "v2" prepare |
3694 | ** interfaces, the underlying reason for the error is returned immediately. |
3695 | ** </li> |
3696 | ** |
3697 | ** <li> |
3698 | ** ^If the specific value bound to [parameter | host parameter] in the |
3699 | ** WHERE clause might influence the choice of query plan for a statement, |
3700 | ** then the statement will be automatically recompiled, as if there had been |
3701 | ** a schema change, on the first [sqlite3_step()] call following any change |
3702 | ** to the [sqlite3_bind_text | bindings] of that [parameter]. |
3703 | ** ^The specific value of WHERE-clause [parameter] might influence the |
3704 | ** choice of query plan if the parameter is the left-hand side of a [LIKE] |
3705 | ** or [GLOB] operator or if the parameter is compared to an indexed column |
3706 | ** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled. |
3707 | ** </li> |
3708 | ** </ol> |
3709 | ** |
3710 | ** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having |
3711 | ** the extra prepFlags parameter, which is a bit array consisting of zero or |
3712 | ** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The |
3713 | ** sqlite3_prepare_v2() interface works exactly the same as |
3714 | ** sqlite3_prepare_v3() with a zero prepFlags parameter. |
3715 | */ |
3716 | SQLITE_API int sqlite3_prepare( |
3717 | sqlite3 *db, /* Database handle */ |
3718 | const char *zSql, /* SQL statement, UTF-8 encoded */ |
3719 | int nByte, /* Maximum length of zSql in bytes. */ |
3720 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
3721 | const char **pzTail /* OUT: Pointer to unused portion of zSql */ |
3722 | ); |
3723 | SQLITE_API int sqlite3_prepare_v2( |
3724 | sqlite3 *db, /* Database handle */ |
3725 | const char *zSql, /* SQL statement, UTF-8 encoded */ |
3726 | int nByte, /* Maximum length of zSql in bytes. */ |
3727 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
3728 | const char **pzTail /* OUT: Pointer to unused portion of zSql */ |
3729 | ); |
3730 | SQLITE_API int sqlite3_prepare_v3( |
3731 | sqlite3 *db, /* Database handle */ |
3732 | const char *zSql, /* SQL statement, UTF-8 encoded */ |
3733 | int nByte, /* Maximum length of zSql in bytes. */ |
3734 | unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ |
3735 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
3736 | const char **pzTail /* OUT: Pointer to unused portion of zSql */ |
3737 | ); |
3738 | SQLITE_API int sqlite3_prepare16( |
3739 | sqlite3 *db, /* Database handle */ |
3740 | const void *zSql, /* SQL statement, UTF-16 encoded */ |
3741 | int nByte, /* Maximum length of zSql in bytes. */ |
3742 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
3743 | const void **pzTail /* OUT: Pointer to unused portion of zSql */ |
3744 | ); |
3745 | SQLITE_API int sqlite3_prepare16_v2( |
3746 | sqlite3 *db, /* Database handle */ |
3747 | const void *zSql, /* SQL statement, UTF-16 encoded */ |
3748 | int nByte, /* Maximum length of zSql in bytes. */ |
3749 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
3750 | const void **pzTail /* OUT: Pointer to unused portion of zSql */ |
3751 | ); |
3752 | SQLITE_API int sqlite3_prepare16_v3( |
3753 | sqlite3 *db, /* Database handle */ |
3754 | const void *zSql, /* SQL statement, UTF-16 encoded */ |
3755 | int nByte, /* Maximum length of zSql in bytes. */ |
3756 | unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ |
3757 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
3758 | const void **pzTail /* OUT: Pointer to unused portion of zSql */ |
3759 | ); |
3760 | |
3761 | /* |
3762 | ** CAPI3REF: Retrieving Statement SQL |
3763 | ** METHOD: sqlite3_stmt |
3764 | ** |
3765 | ** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8 |
3766 | ** SQL text used to create [prepared statement] P if P was |
3767 | ** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], |
3768 | ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. |
3769 | ** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8 |
3770 | ** string containing the SQL text of prepared statement P with |
3771 | ** [bound parameters] expanded. |
3772 | ** |
3773 | ** ^(For example, if a prepared statement is created using the SQL |
3774 | ** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345 |
3775 | ** and parameter :xyz is unbound, then sqlite3_sql() will return |
3776 | ** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql() |
3777 | ** will return "SELECT 2345,NULL".)^ |
3778 | ** |
3779 | ** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory |
3780 | ** is available to hold the result, or if the result would exceed the |
3781 | ** the maximum string length determined by the [SQLITE_LIMIT_LENGTH]. |
3782 | ** |
3783 | ** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of |
3784 | ** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time |
3785 | ** option causes sqlite3_expanded_sql() to always return NULL. |
3786 | ** |
3787 | ** ^The string returned by sqlite3_sql(P) is managed by SQLite and is |
3788 | ** automatically freed when the prepared statement is finalized. |
3789 | ** ^The string returned by sqlite3_expanded_sql(P), on the other hand, |
3790 | ** is obtained from [sqlite3_malloc()] and must be free by the application |
3791 | ** by passing it to [sqlite3_free()]. |
3792 | */ |
3793 | SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt); |
3794 | SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt); |
3795 | |
3796 | /* |
3797 | ** CAPI3REF: Determine If An SQL Statement Writes The Database |
3798 | ** METHOD: sqlite3_stmt |
3799 | ** |
3800 | ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if |
3801 | ** and only if the [prepared statement] X makes no direct changes to |
3802 | ** the content of the database file. |
3803 | ** |
3804 | ** Note that [application-defined SQL functions] or |
3805 | ** [virtual tables] might change the database indirectly as a side effect. |
3806 | ** ^(For example, if an application defines a function "eval()" that |
3807 | ** calls [sqlite3_exec()], then the following SQL statement would |
3808 | ** change the database file through side-effects: |
3809 | ** |
3810 | ** <blockquote><pre> |
3811 | ** SELECT eval('DELETE FROM t1') FROM t2; |
3812 | ** </pre></blockquote> |
3813 | ** |
3814 | ** But because the [SELECT] statement does not change the database file |
3815 | ** directly, sqlite3_stmt_readonly() would still return true.)^ |
3816 | ** |
3817 | ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK], |
3818 | ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true, |
3819 | ** since the statements themselves do not actually modify the database but |
3820 | ** rather they control the timing of when other statements modify the |
3821 | ** database. ^The [ATTACH] and [DETACH] statements also cause |
3822 | ** sqlite3_stmt_readonly() to return true since, while those statements |
3823 | ** change the configuration of a database connection, they do not make |
3824 | ** changes to the content of the database files on disk. |
3825 | ** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since |
3826 | ** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and |
3827 | ** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so |
3828 | ** sqlite3_stmt_readonly() returns false for those commands. |
3829 | */ |
3830 | SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt); |
3831 | |
3832 | /* |
3833 | ** CAPI3REF: Determine If A Prepared Statement Has Been Reset |
3834 | ** METHOD: sqlite3_stmt |
3835 | ** |
3836 | ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the |
3837 | ** [prepared statement] S has been stepped at least once using |
3838 | ** [sqlite3_step(S)] but has neither run to completion (returned |
3839 | ** [SQLITE_DONE] from [sqlite3_step(S)]) nor |
3840 | ** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S) |
3841 | ** interface returns false if S is a NULL pointer. If S is not a |
3842 | ** NULL pointer and is not a pointer to a valid [prepared statement] |
3843 | ** object, then the behavior is undefined and probably undesirable. |
3844 | ** |
3845 | ** This interface can be used in combination [sqlite3_next_stmt()] |
3846 | ** to locate all prepared statements associated with a database |
3847 | ** connection that are in need of being reset. This can be used, |
3848 | ** for example, in diagnostic routines to search for prepared |
3849 | ** statements that are holding a transaction open. |
3850 | */ |
3851 | SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*); |
3852 | |
3853 | /* |
3854 | ** CAPI3REF: Dynamically Typed Value Object |
3855 | ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} |
3856 | ** |
3857 | ** SQLite uses the sqlite3_value object to represent all values |
3858 | ** that can be stored in a database table. SQLite uses dynamic typing |
3859 | ** for the values it stores. ^Values stored in sqlite3_value objects |
3860 | ** can be integers, floating point values, strings, BLOBs, or NULL. |
3861 | ** |
3862 | ** An sqlite3_value object may be either "protected" or "unprotected". |
3863 | ** Some interfaces require a protected sqlite3_value. Other interfaces |
3864 | ** will accept either a protected or an unprotected sqlite3_value. |
3865 | ** Every interface that accepts sqlite3_value arguments specifies |
3866 | ** whether or not it requires a protected sqlite3_value. The |
3867 | ** [sqlite3_value_dup()] interface can be used to construct a new |
3868 | ** protected sqlite3_value from an unprotected sqlite3_value. |
3869 | ** |
3870 | ** The terms "protected" and "unprotected" refer to whether or not |
3871 | ** a mutex is held. An internal mutex is held for a protected |
3872 | ** sqlite3_value object but no mutex is held for an unprotected |
3873 | ** sqlite3_value object. If SQLite is compiled to be single-threaded |
3874 | ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) |
3875 | ** or if SQLite is run in one of reduced mutex modes |
3876 | ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] |
3877 | ** then there is no distinction between protected and unprotected |
3878 | ** sqlite3_value objects and they can be used interchangeably. However, |
3879 | ** for maximum code portability it is recommended that applications |
3880 | ** still make the distinction between protected and unprotected |
3881 | ** sqlite3_value objects even when not strictly required. |
3882 | ** |
3883 | ** ^The sqlite3_value objects that are passed as parameters into the |
3884 | ** implementation of [application-defined SQL functions] are protected. |
3885 | ** ^The sqlite3_value object returned by |
3886 | ** [sqlite3_column_value()] is unprotected. |
3887 | ** Unprotected sqlite3_value objects may only be used as arguments |
3888 | ** to [sqlite3_result_value()], [sqlite3_bind_value()], and |
3889 | ** [sqlite3_value_dup()]. |
3890 | ** The [sqlite3_value_blob | sqlite3_value_type()] family of |
3891 | ** interfaces require protected sqlite3_value objects. |
3892 | */ |
3893 | typedef struct sqlite3_value sqlite3_value; |
3894 | |
3895 | /* |
3896 | ** CAPI3REF: SQL Function Context Object |
3897 | ** |
3898 | ** The context in which an SQL function executes is stored in an |
3899 | ** sqlite3_context object. ^A pointer to an sqlite3_context object |
3900 | ** is always first parameter to [application-defined SQL functions]. |
3901 | ** The application-defined SQL function implementation will pass this |
3902 | ** pointer through into calls to [sqlite3_result_int | sqlite3_result()], |
3903 | ** [sqlite3_aggregate_context()], [sqlite3_user_data()], |
3904 | ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], |
3905 | ** and/or [sqlite3_set_auxdata()]. |
3906 | */ |
3907 | typedef struct sqlite3_context sqlite3_context; |
3908 | |
3909 | /* |
3910 | ** CAPI3REF: Binding Values To Prepared Statements |
3911 | ** KEYWORDS: {host parameter} {host parameters} {host parameter name} |
3912 | ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} |
3913 | ** METHOD: sqlite3_stmt |
3914 | ** |
3915 | ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants, |
3916 | ** literals may be replaced by a [parameter] that matches one of following |
3917 | ** templates: |
3918 | ** |
3919 | ** <ul> |
3920 | ** <li> ? |
3921 | ** <li> ?NNN |
3922 | ** <li> :VVV |
3923 | ** <li> @VVV |
3924 | ** <li> $VVV |
3925 | ** </ul> |
3926 | ** |
3927 | ** In the templates above, NNN represents an integer literal, |
3928 | ** and VVV represents an alphanumeric identifier.)^ ^The values of these |
3929 | ** parameters (also called "host parameter names" or "SQL parameters") |
3930 | ** can be set using the sqlite3_bind_*() routines defined here. |
3931 | ** |
3932 | ** ^The first argument to the sqlite3_bind_*() routines is always |
3933 | ** a pointer to the [sqlite3_stmt] object returned from |
3934 | ** [sqlite3_prepare_v2()] or its variants. |
3935 | ** |
3936 | ** ^The second argument is the index of the SQL parameter to be set. |
3937 | ** ^The leftmost SQL parameter has an index of 1. ^When the same named |
3938 | ** SQL parameter is used more than once, second and subsequent |
3939 | ** occurrences have the same index as the first occurrence. |
3940 | ** ^The index for named parameters can be looked up using the |
3941 | ** [sqlite3_bind_parameter_index()] API if desired. ^The index |
3942 | ** for "?NNN" parameters is the value of NNN. |
3943 | ** ^The NNN value must be between 1 and the [sqlite3_limit()] |
3944 | ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999). |
3945 | ** |
3946 | ** ^The third argument is the value to bind to the parameter. |
3947 | ** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16() |
3948 | ** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter |
3949 | ** is ignored and the end result is the same as sqlite3_bind_null(). |
3950 | ** |
3951 | ** ^(In those routines that have a fourth argument, its value is the |
3952 | ** number of bytes in the parameter. To be clear: the value is the |
3953 | ** number of <u>bytes</u> in the value, not the number of characters.)^ |
3954 | ** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16() |
3955 | ** is negative, then the length of the string is |
3956 | ** the number of bytes up to the first zero terminator. |
3957 | ** If the fourth parameter to sqlite3_bind_blob() is negative, then |
3958 | ** the behavior is undefined. |
3959 | ** If a non-negative fourth parameter is provided to sqlite3_bind_text() |
3960 | ** or sqlite3_bind_text16() or sqlite3_bind_text64() then |
3961 | ** that parameter must be the byte offset |
3962 | ** where the NUL terminator would occur assuming the string were NUL |
3963 | ** terminated. If any NUL characters occur at byte offsets less than |
3964 | ** the value of the fourth parameter then the resulting string value will |
3965 | ** contain embedded NULs. The result of expressions involving strings |
3966 | ** with embedded NULs is undefined. |
3967 | ** |
3968 | ** ^The fifth argument to the BLOB and string binding interfaces |
3969 | ** is a destructor used to dispose of the BLOB or |
3970 | ** string after SQLite has finished with it. ^The destructor is called |
3971 | ** to dispose of the BLOB or string even if the call to bind API fails. |
3972 | ** ^If the fifth argument is |
3973 | ** the special value [SQLITE_STATIC], then SQLite assumes that the |
3974 | ** information is in static, unmanaged space and does not need to be freed. |
3975 | ** ^If the fifth argument has the value [SQLITE_TRANSIENT], then |
3976 | ** SQLite makes its own private copy of the data immediately, before |
3977 | ** the sqlite3_bind_*() routine returns. |
3978 | ** |
3979 | ** ^The sixth argument to sqlite3_bind_text64() must be one of |
3980 | ** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE] |
3981 | ** to specify the encoding of the text in the third parameter. If |
3982 | ** the sixth argument to sqlite3_bind_text64() is not one of the |
3983 | ** allowed values shown above, or if the text encoding is different |
3984 | ** from the encoding specified by the sixth parameter, then the behavior |
3985 | ** is undefined. |
3986 | ** |
3987 | ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that |
3988 | ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory |
3989 | ** (just an integer to hold its size) while it is being processed. |
3990 | ** Zeroblobs are intended to serve as placeholders for BLOBs whose |
3991 | ** content is later written using |
3992 | ** [sqlite3_blob_open | incremental BLOB I/O] routines. |
3993 | ** ^A negative value for the zeroblob results in a zero-length BLOB. |
3994 | ** |
3995 | ** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in |
3996 | ** [prepared statement] S to have an SQL value of NULL, but to also be |
3997 | ** associated with the pointer P of type T. ^D is either a NULL pointer or |
3998 | ** a pointer to a destructor function for P. ^SQLite will invoke the |
3999 | ** destructor D with a single argument of P when it is finished using |
4000 | ** P. The T parameter should be a static string, preferably a string |
4001 | ** literal. The sqlite3_bind_pointer() routine is part of the |
4002 | ** [pointer passing interface] added for SQLite 3.20.0. |
4003 | ** |
4004 | ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer |
4005 | ** for the [prepared statement] or with a prepared statement for which |
4006 | ** [sqlite3_step()] has been called more recently than [sqlite3_reset()], |
4007 | ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_() |
4008 | ** routine is passed a [prepared statement] that has been finalized, the |
4009 | ** result is undefined and probably harmful. |
4010 | ** |
4011 | ** ^Bindings are not cleared by the [sqlite3_reset()] routine. |
4012 | ** ^Unbound parameters are interpreted as NULL. |
4013 | ** |
4014 | ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an |
4015 | ** [error code] if anything goes wrong. |
4016 | ** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB |
4017 | ** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or |
4018 | ** [SQLITE_MAX_LENGTH]. |
4019 | ** ^[SQLITE_RANGE] is returned if the parameter |
4020 | ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails. |
4021 | ** |
4022 | ** See also: [sqlite3_bind_parameter_count()], |
4023 | ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. |
4024 | */ |
4025 | SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); |
4026 | SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64, |
4027 | void(*)(void*)); |
4028 | SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double); |
4029 | SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int); |
4030 | SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); |
4031 | SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int); |
4032 | SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*)); |
4033 | SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); |
4034 | SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64, |
4035 | void(*)(void*), unsigned char encoding); |
4036 | SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); |
4037 | SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*)); |
4038 | SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); |
4039 | SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64); |
4040 | |
4041 | /* |
4042 | ** CAPI3REF: Number Of SQL Parameters |
4043 | ** METHOD: sqlite3_stmt |
4044 | ** |
4045 | ** ^This routine can be used to find the number of [SQL parameters] |
4046 | ** in a [prepared statement]. SQL parameters are tokens of the |
4047 | ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as |
4048 | ** placeholders for values that are [sqlite3_bind_blob | bound] |
4049 | ** to the parameters at a later time. |
4050 | ** |
4051 | ** ^(This routine actually returns the index of the largest (rightmost) |
4052 | ** parameter. For all forms except ?NNN, this will correspond to the |
4053 | ** number of unique parameters. If parameters of the ?NNN form are used, |
4054 | ** there may be gaps in the list.)^ |
4055 | ** |
4056 | ** See also: [sqlite3_bind_blob|sqlite3_bind()], |
4057 | ** [sqlite3_bind_parameter_name()], and |
4058 | ** [sqlite3_bind_parameter_index()]. |
4059 | */ |
4060 | SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*); |
4061 | |
4062 | /* |
4063 | ** CAPI3REF: Name Of A Host Parameter |
4064 | ** METHOD: sqlite3_stmt |
4065 | ** |
4066 | ** ^The sqlite3_bind_parameter_name(P,N) interface returns |
4067 | ** the name of the N-th [SQL parameter] in the [prepared statement] P. |
4068 | ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" |
4069 | ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" |
4070 | ** respectively. |
4071 | ** In other words, the initial ":" or "$" or "@" or "?" |
4072 | ** is included as part of the name.)^ |
4073 | ** ^Parameters of the form "?" without a following integer have no name |
4074 | ** and are referred to as "nameless" or "anonymous parameters". |
4075 | ** |
4076 | ** ^The first host parameter has an index of 1, not 0. |
4077 | ** |
4078 | ** ^If the value N is out of range or if the N-th parameter is |
4079 | ** nameless, then NULL is returned. ^The returned string is |
4080 | ** always in UTF-8 encoding even if the named parameter was |
4081 | ** originally specified as UTF-16 in [sqlite3_prepare16()], |
4082 | ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. |
4083 | ** |
4084 | ** See also: [sqlite3_bind_blob|sqlite3_bind()], |
4085 | ** [sqlite3_bind_parameter_count()], and |
4086 | ** [sqlite3_bind_parameter_index()]. |
4087 | */ |
4088 | SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); |
4089 | |
4090 | /* |
4091 | ** CAPI3REF: Index Of A Parameter With A Given Name |
4092 | ** METHOD: sqlite3_stmt |
4093 | ** |
4094 | ** ^Return the index of an SQL parameter given its name. ^The |
4095 | ** index value returned is suitable for use as the second |
4096 | ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero |
4097 | ** is returned if no matching parameter is found. ^The parameter |
4098 | ** name must be given in UTF-8 even if the original statement |
4099 | ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or |
4100 | ** [sqlite3_prepare16_v3()]. |
4101 | ** |
4102 | ** See also: [sqlite3_bind_blob|sqlite3_bind()], |
4103 | ** [sqlite3_bind_parameter_count()], and |
4104 | ** [sqlite3_bind_parameter_name()]. |
4105 | */ |
4106 | SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); |
4107 | |
4108 | /* |
4109 | ** CAPI3REF: Reset All Bindings On A Prepared Statement |
4110 | ** METHOD: sqlite3_stmt |
4111 | ** |
4112 | ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset |
4113 | ** the [sqlite3_bind_blob | bindings] on a [prepared statement]. |
4114 | ** ^Use this routine to reset all host parameters to NULL. |
4115 | */ |
4116 | SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*); |
4117 | |
4118 | /* |
4119 | ** CAPI3REF: Number Of Columns In A Result Set |
4120 | ** METHOD: sqlite3_stmt |
4121 | ** |
4122 | ** ^Return the number of columns in the result set returned by the |
4123 | ** [prepared statement]. ^If this routine returns 0, that means the |
4124 | ** [prepared statement] returns no data (for example an [UPDATE]). |
4125 | ** ^However, just because this routine returns a positive number does not |
4126 | ** mean that one or more rows of data will be returned. ^A SELECT statement |
4127 | ** will always have a positive sqlite3_column_count() but depending on the |
4128 | ** WHERE clause constraints and the table content, it might return no rows. |
4129 | ** |
4130 | ** See also: [sqlite3_data_count()] |
4131 | */ |
4132 | SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt); |
4133 | |
4134 | /* |
4135 | ** CAPI3REF: Column Names In A Result Set |
4136 | ** METHOD: sqlite3_stmt |
4137 | ** |
4138 | ** ^These routines return the name assigned to a particular column |
4139 | ** in the result set of a [SELECT] statement. ^The sqlite3_column_name() |
4140 | ** interface returns a pointer to a zero-terminated UTF-8 string |
4141 | ** and sqlite3_column_name16() returns a pointer to a zero-terminated |
4142 | ** UTF-16 string. ^The first parameter is the [prepared statement] |
4143 | ** that implements the [SELECT] statement. ^The second parameter is the |
4144 | ** column number. ^The leftmost column is number 0. |
4145 | ** |
4146 | ** ^The returned string pointer is valid until either the [prepared statement] |
4147 | ** is destroyed by [sqlite3_finalize()] or until the statement is automatically |
4148 | ** reprepared by the first call to [sqlite3_step()] for a particular run |
4149 | ** or until the next call to |
4150 | ** sqlite3_column_name() or sqlite3_column_name16() on the same column. |
4151 | ** |
4152 | ** ^If sqlite3_malloc() fails during the processing of either routine |
4153 | ** (for example during a conversion from UTF-8 to UTF-16) then a |
4154 | ** NULL pointer is returned. |
4155 | ** |
4156 | ** ^The name of a result column is the value of the "AS" clause for |
4157 | ** that column, if there is an AS clause. If there is no AS clause |
4158 | ** then the name of the column is unspecified and may change from |
4159 | ** one release of SQLite to the next. |
4160 | */ |
4161 | SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N); |
4162 | SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N); |
4163 | |
4164 | /* |
4165 | ** CAPI3REF: Source Of Data In A Query Result |
4166 | ** METHOD: sqlite3_stmt |
4167 | ** |
4168 | ** ^These routines provide a means to determine the database, table, and |
4169 | ** table column that is the origin of a particular result column in |
4170 | ** [SELECT] statement. |
4171 | ** ^The name of the database or table or column can be returned as |
4172 | ** either a UTF-8 or UTF-16 string. ^The _database_ routines return |
4173 | ** the database name, the _table_ routines return the table name, and |
4174 | ** the origin_ routines return the column name. |
4175 | ** ^The returned string is valid until the [prepared statement] is destroyed |
4176 | ** using [sqlite3_finalize()] or until the statement is automatically |
4177 | ** reprepared by the first call to [sqlite3_step()] for a particular run |
4178 | ** or until the same information is requested |
4179 | ** again in a different encoding. |
4180 | ** |
4181 | ** ^The names returned are the original un-aliased names of the |
4182 | ** database, table, and column. |
4183 | ** |
4184 | ** ^The first argument to these interfaces is a [prepared statement]. |
4185 | ** ^These functions return information about the Nth result column returned by |
4186 | ** the statement, where N is the second function argument. |
4187 | ** ^The left-most column is column 0 for these routines. |
4188 | ** |
4189 | ** ^If the Nth column returned by the statement is an expression or |
4190 | ** subquery and is not a column value, then all of these functions return |
4191 | ** NULL. ^These routine might also return NULL if a memory allocation error |
4192 | ** occurs. ^Otherwise, they return the name of the attached database, table, |
4193 | ** or column that query result column was extracted from. |
4194 | ** |
4195 | ** ^As with all other SQLite APIs, those whose names end with "16" return |
4196 | ** UTF-16 encoded strings and the other functions return UTF-8. |
4197 | ** |
4198 | ** ^These APIs are only available if the library was compiled with the |
4199 | ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol. |
4200 | ** |
4201 | ** If two or more threads call one or more of these routines against the same |
4202 | ** prepared statement and column at the same time then the results are |
4203 | ** undefined. |
4204 | ** |
4205 | ** If two or more threads call one or more |
4206 | ** [sqlite3_column_database_name | column metadata interfaces] |
4207 | ** for the same [prepared statement] and result column |
4208 | ** at the same time then the results are undefined. |
4209 | */ |
4210 | SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int); |
4211 | SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int); |
4212 | SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int); |
4213 | SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int); |
4214 | SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int); |
4215 | SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); |
4216 | |
4217 | /* |
4218 | ** CAPI3REF: Declared Datatype Of A Query Result |
4219 | ** METHOD: sqlite3_stmt |
4220 | ** |
4221 | ** ^(The first parameter is a [prepared statement]. |
4222 | ** If this statement is a [SELECT] statement and the Nth column of the |
4223 | ** returned result set of that [SELECT] is a table column (not an |
4224 | ** expression or subquery) then the declared type of the table |
4225 | ** column is returned.)^ ^If the Nth column of the result set is an |
4226 | ** expression or subquery, then a NULL pointer is returned. |
4227 | ** ^The returned string is always UTF-8 encoded. |
4228 | ** |
4229 | ** ^(For example, given the database schema: |
4230 | ** |
4231 | ** CREATE TABLE t1(c1 VARIANT); |
4232 | ** |
4233 | ** and the following statement to be compiled: |
4234 | ** |
4235 | ** SELECT c1 + 1, c1 FROM t1; |
4236 | ** |
4237 | ** this routine would return the string "VARIANT" for the second result |
4238 | ** column (i==1), and a NULL pointer for the first result column (i==0).)^ |
4239 | ** |
4240 | ** ^SQLite uses dynamic run-time typing. ^So just because a column |
4241 | ** is declared to contain a particular type does not mean that the |
4242 | ** data stored in that column is of the declared type. SQLite is |
4243 | ** strongly typed, but the typing is dynamic not static. ^Type |
4244 | ** is associated with individual values, not with the containers |
4245 | ** used to hold those values. |
4246 | */ |
4247 | SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int); |
4248 | SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int); |
4249 | |
4250 | /* |
4251 | ** CAPI3REF: Evaluate An SQL Statement |
4252 | ** METHOD: sqlite3_stmt |
4253 | ** |
4254 | ** After a [prepared statement] has been prepared using any of |
4255 | ** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()], |
4256 | ** or [sqlite3_prepare16_v3()] or one of the legacy |
4257 | ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function |
4258 | ** must be called one or more times to evaluate the statement. |
4259 | ** |
4260 | ** The details of the behavior of the sqlite3_step() interface depend |
4261 | ** on whether the statement was prepared using the newer "vX" interfaces |
4262 | ** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()], |
4263 | ** [sqlite3_prepare16_v2()] or the older legacy |
4264 | ** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the |
4265 | ** new "vX" interface is recommended for new applications but the legacy |
4266 | ** interface will continue to be supported. |
4267 | ** |
4268 | ** ^In the legacy interface, the return value will be either [SQLITE_BUSY], |
4269 | ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. |
4270 | ** ^With the "v2" interface, any of the other [result codes] or |
4271 | ** [extended result codes] might be returned as well. |
4272 | ** |
4273 | ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the |
4274 | ** database locks it needs to do its job. ^If the statement is a [COMMIT] |
4275 | ** or occurs outside of an explicit transaction, then you can retry the |
4276 | ** statement. If the statement is not a [COMMIT] and occurs within an |
4277 | ** explicit transaction then you should rollback the transaction before |
4278 | ** continuing. |
4279 | ** |
4280 | ** ^[SQLITE_DONE] means that the statement has finished executing |
4281 | ** successfully. sqlite3_step() should not be called again on this virtual |
4282 | ** machine without first calling [sqlite3_reset()] to reset the virtual |
4283 | ** machine back to its initial state. |
4284 | ** |
4285 | ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW] |
4286 | ** is returned each time a new row of data is ready for processing by the |
4287 | ** caller. The values may be accessed using the [column access functions]. |
4288 | ** sqlite3_step() is called again to retrieve the next row of data. |
4289 | ** |
4290 | ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint |
4291 | ** violation) has occurred. sqlite3_step() should not be called again on |
4292 | ** the VM. More information may be found by calling [sqlite3_errmsg()]. |
4293 | ** ^With the legacy interface, a more specific error code (for example, |
4294 | ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) |
4295 | ** can be obtained by calling [sqlite3_reset()] on the |
4296 | ** [prepared statement]. ^In the "v2" interface, |
4297 | ** the more specific error code is returned directly by sqlite3_step(). |
4298 | ** |
4299 | ** [SQLITE_MISUSE] means that the this routine was called inappropriately. |
4300 | ** Perhaps it was called on a [prepared statement] that has |
4301 | ** already been [sqlite3_finalize | finalized] or on one that had |
4302 | ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could |
4303 | ** be the case that the same database connection is being used by two or |
4304 | ** more threads at the same moment in time. |
4305 | ** |
4306 | ** For all versions of SQLite up to and including 3.6.23.1, a call to |
4307 | ** [sqlite3_reset()] was required after sqlite3_step() returned anything |
4308 | ** other than [SQLITE_ROW] before any subsequent invocation of |
4309 | ** sqlite3_step(). Failure to reset the prepared statement using |
4310 | ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from |
4311 | ** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1], |
4312 | ** sqlite3_step() began |
4313 | ** calling [sqlite3_reset()] automatically in this circumstance rather |
4314 | ** than returning [SQLITE_MISUSE]. This is not considered a compatibility |
4315 | ** break because any application that ever receives an SQLITE_MISUSE error |
4316 | ** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option |
4317 | ** can be used to restore the legacy behavior. |
4318 | ** |
4319 | ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step() |
4320 | ** API always returns a generic error code, [SQLITE_ERROR], following any |
4321 | ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call |
4322 | ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the |
4323 | ** specific [error codes] that better describes the error. |
4324 | ** We admit that this is a goofy design. The problem has been fixed |
4325 | ** with the "v2" interface. If you prepare all of your SQL statements |
4326 | ** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()] |
4327 | ** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead |
4328 | ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, |
4329 | ** then the more specific [error codes] are returned directly |
4330 | ** by sqlite3_step(). The use of the "vX" interfaces is recommended. |
4331 | */ |
4332 | SQLITE_API int sqlite3_step(sqlite3_stmt*); |
4333 | |
4334 | /* |
4335 | ** CAPI3REF: Number of columns in a result set |
4336 | ** METHOD: sqlite3_stmt |
4337 | ** |
4338 | ** ^The sqlite3_data_count(P) interface returns the number of columns in the |
4339 | ** current row of the result set of [prepared statement] P. |
4340 | ** ^If prepared statement P does not have results ready to return |
4341 | ** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of |
4342 | ** interfaces) then sqlite3_data_count(P) returns 0. |
4343 | ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer. |
4344 | ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to |
4345 | ** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P) |
4346 | ** will return non-zero if previous call to [sqlite3_step](P) returned |
4347 | ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum] |
4348 | ** where it always returns zero since each step of that multi-step |
4349 | ** pragma returns 0 columns of data. |
4350 | ** |
4351 | ** See also: [sqlite3_column_count()] |
4352 | */ |
4353 | SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt); |
4354 | |
4355 | /* |
4356 | ** CAPI3REF: Fundamental Datatypes |
4357 | ** KEYWORDS: SQLITE_TEXT |
4358 | ** |
4359 | ** ^(Every value in SQLite has one of five fundamental datatypes: |
4360 | ** |
4361 | ** <ul> |
4362 | ** <li> 64-bit signed integer |
4363 | ** <li> 64-bit IEEE floating point number |
4364 | ** <li> string |
4365 | ** <li> BLOB |
4366 | ** <li> NULL |
4367 | ** </ul>)^ |
4368 | ** |
4369 | ** These constants are codes for each of those types. |
4370 | ** |
4371 | ** Note that the SQLITE_TEXT constant was also used in SQLite version 2 |
4372 | ** for a completely different meaning. Software that links against both |
4373 | ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not |
4374 | ** SQLITE_TEXT. |
4375 | */ |
4376 | #define SQLITE_INTEGER 1 |
4377 | #define SQLITE_FLOAT 2 |
4378 | #define SQLITE_BLOB 4 |
4379 | #define SQLITE_NULL 5 |
4380 | #ifdef SQLITE_TEXT |
4381 | # undef SQLITE_TEXT |
4382 | #else |
4383 | # define SQLITE_TEXT 3 |
4384 | #endif |
4385 | #define SQLITE3_TEXT 3 |
4386 | |
4387 | /* |
4388 | ** CAPI3REF: Result Values From A Query |
4389 | ** KEYWORDS: {column access functions} |
4390 | ** METHOD: sqlite3_stmt |
4391 | ** |
4392 | ** <b>Summary:</b> |
4393 | ** <blockquote><table border=0 cellpadding=0 cellspacing=0> |
4394 | ** <tr><td><b>sqlite3_column_blob</b><td>→<td>BLOB result |
4395 | ** <tr><td><b>sqlite3_column_double</b><td>→<td>REAL result |
4396 | ** <tr><td><b>sqlite3_column_int</b><td>→<td>32-bit INTEGER result |
4397 | ** <tr><td><b>sqlite3_column_int64</b><td>→<td>64-bit INTEGER result |
4398 | ** <tr><td><b>sqlite3_column_text</b><td>→<td>UTF-8 TEXT result |
4399 | ** <tr><td><b>sqlite3_column_text16</b><td>→<td>UTF-16 TEXT result |
4400 | ** <tr><td><b>sqlite3_column_value</b><td>→<td>The result as an |
4401 | ** [sqlite3_value|unprotected sqlite3_value] object. |
4402 | ** <tr><td> <td> <td> |
4403 | ** <tr><td><b>sqlite3_column_bytes</b><td>→<td>Size of a BLOB |
4404 | ** or a UTF-8 TEXT result in bytes |
4405 | ** <tr><td><b>sqlite3_column_bytes16 </b> |
4406 | ** <td>→ <td>Size of UTF-16 |
4407 | ** TEXT in bytes |
4408 | ** <tr><td><b>sqlite3_column_type</b><td>→<td>Default |
4409 | ** datatype of the result |
4410 | ** </table></blockquote> |
4411 | ** |
4412 | ** <b>Details:</b> |
4413 | ** |
4414 | ** ^These routines return information about a single column of the current |
4415 | ** result row of a query. ^In every case the first argument is a pointer |
4416 | ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] |
4417 | ** that was returned from [sqlite3_prepare_v2()] or one of its variants) |
4418 | ** and the second argument is the index of the column for which information |
4419 | ** should be returned. ^The leftmost column of the result set has the index 0. |
4420 | ** ^The number of columns in the result can be determined using |
4421 | ** [sqlite3_column_count()]. |
4422 | ** |
4423 | ** If the SQL statement does not currently point to a valid row, or if the |
4424 | ** column index is out of range, the result is undefined. |
4425 | ** These routines may only be called when the most recent call to |
4426 | ** [sqlite3_step()] has returned [SQLITE_ROW] and neither |
4427 | ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. |
4428 | ** If any of these routines are called after [sqlite3_reset()] or |
4429 | ** [sqlite3_finalize()] or after [sqlite3_step()] has returned |
4430 | ** something other than [SQLITE_ROW], the results are undefined. |
4431 | ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] |
4432 | ** are called from a different thread while any of these routines |
4433 | ** are pending, then the results are undefined. |
4434 | ** |
4435 | ** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16) |
4436 | ** each return the value of a result column in a specific data format. If |
4437 | ** the result column is not initially in the requested format (for example, |
4438 | ** if the query returns an integer but the sqlite3_column_text() interface |
4439 | ** is used to extract the value) then an automatic type conversion is performed. |
4440 | ** |
4441 | ** ^The sqlite3_column_type() routine returns the |
4442 | ** [SQLITE_INTEGER | datatype code] for the initial data type |
4443 | ** of the result column. ^The returned value is one of [SQLITE_INTEGER], |
4444 | ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. |
4445 | ** The return value of sqlite3_column_type() can be used to decide which |
4446 | ** of the first six interface should be used to extract the column value. |
4447 | ** The value returned by sqlite3_column_type() is only meaningful if no |
4448 | ** automatic type conversions have occurred for the value in question. |
4449 | ** After a type conversion, the result of calling sqlite3_column_type() |
4450 | ** is undefined, though harmless. Future |
4451 | ** versions of SQLite may change the behavior of sqlite3_column_type() |
4452 | ** following a type conversion. |
4453 | ** |
4454 | ** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes() |
4455 | ** or sqlite3_column_bytes16() interfaces can be used to determine the size |
4456 | ** of that BLOB or string. |
4457 | ** |
4458 | ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() |
4459 | ** routine returns the number of bytes in that BLOB or string. |
4460 | ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts |
4461 | ** the string to UTF-8 and then returns the number of bytes. |
4462 | ** ^If the result is a numeric value then sqlite3_column_bytes() uses |
4463 | ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns |
4464 | ** the number of bytes in that string. |
4465 | ** ^If the result is NULL, then sqlite3_column_bytes() returns zero. |
4466 | ** |
4467 | ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16() |
4468 | ** routine returns the number of bytes in that BLOB or string. |
4469 | ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts |
4470 | ** the string to UTF-16 and then returns the number of bytes. |
4471 | ** ^If the result is a numeric value then sqlite3_column_bytes16() uses |
4472 | ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns |
4473 | ** the number of bytes in that string. |
4474 | ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero. |
4475 | ** |
4476 | ** ^The values returned by [sqlite3_column_bytes()] and |
4477 | ** [sqlite3_column_bytes16()] do not include the zero terminators at the end |
4478 | ** of the string. ^For clarity: the values returned by |
4479 | ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of |
4480 | ** bytes in the string, not the number of characters. |
4481 | ** |
4482 | ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(), |
4483 | ** even empty strings, are always zero-terminated. ^The return |
4484 | ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer. |
4485 | ** |
4486 | ** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an |
4487 | ** [unprotected sqlite3_value] object. In a multithreaded environment, |
4488 | ** an unprotected sqlite3_value object may only be used safely with |
4489 | ** [sqlite3_bind_value()] and [sqlite3_result_value()]. |
4490 | ** If the [unprotected sqlite3_value] object returned by |
4491 | ** [sqlite3_column_value()] is used in any other way, including calls |
4492 | ** to routines like [sqlite3_value_int()], [sqlite3_value_text()], |
4493 | ** or [sqlite3_value_bytes()], the behavior is not threadsafe. |
4494 | ** Hence, the sqlite3_column_value() interface |
4495 | ** is normally only useful within the implementation of |
4496 | ** [application-defined SQL functions] or [virtual tables], not within |
4497 | ** top-level application code. |
4498 | ** |
4499 | ** The these routines may attempt to convert the datatype of the result. |
4500 | ** ^For example, if the internal representation is FLOAT and a text result |
4501 | ** is requested, [sqlite3_snprintf()] is used internally to perform the |
4502 | ** conversion automatically. ^(The following table details the conversions |
4503 | ** that are applied: |
4504 | ** |
4505 | ** <blockquote> |
4506 | ** <table border="1"> |
4507 | ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion |
4508 | ** |
4509 | ** <tr><td> NULL <td> INTEGER <td> Result is 0 |
4510 | ** <tr><td> NULL <td> FLOAT <td> Result is 0.0 |
4511 | ** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer |
4512 | ** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer |
4513 | ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float |
4514 | ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer |
4515 | ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT |
4516 | ** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER |
4517 | ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float |
4518 | ** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB |
4519 | ** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER |
4520 | ** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL |
4521 | ** <tr><td> TEXT <td> BLOB <td> No change |
4522 | ** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER |
4523 | ** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL |
4524 | ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed |
4525 | ** </table> |
4526 | ** </blockquote>)^ |
4527 | ** |
4528 | ** Note that when type conversions occur, pointers returned by prior |
4529 | ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or |
4530 | ** sqlite3_column_text16() may be invalidated. |
4531 | ** Type conversions and pointer invalidations might occur |
4532 | ** in the following cases: |
4533 | ** |
4534 | ** <ul> |
4535 | ** <li> The initial content is a BLOB and sqlite3_column_text() or |
4536 | ** sqlite3_column_text16() is called. A zero-terminator might |
4537 | ** need to be added to the string.</li> |
4538 | ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or |
4539 | ** sqlite3_column_text16() is called. The content must be converted |
4540 | ** to UTF-16.</li> |
4541 | ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or |
4542 | ** sqlite3_column_text() is called. The content must be converted |
4543 | ** to UTF-8.</li> |
4544 | ** </ul> |
4545 | ** |
4546 | ** ^Conversions between UTF-16be and UTF-16le are always done in place and do |
4547 | ** not invalidate a prior pointer, though of course the content of the buffer |
4548 | ** that the prior pointer references will have been modified. Other kinds |
4549 | ** of conversion are done in place when it is possible, but sometimes they |
4550 | ** are not possible and in those cases prior pointers are invalidated. |
4551 | ** |
4552 | ** The safest policy is to invoke these routines |
4553 | ** in one of the following ways: |
4554 | ** |
4555 | ** <ul> |
4556 | ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> |
4557 | ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> |
4558 | ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> |
4559 | ** </ul> |
4560 | ** |
4561 | ** In other words, you should call sqlite3_column_text(), |
4562 | ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result |
4563 | ** into the desired format, then invoke sqlite3_column_bytes() or |
4564 | ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls |
4565 | ** to sqlite3_column_text() or sqlite3_column_blob() with calls to |
4566 | ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() |
4567 | ** with calls to sqlite3_column_bytes(). |
4568 | ** |
4569 | ** ^The pointers returned are valid until a type conversion occurs as |
4570 | ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or |
4571 | ** [sqlite3_finalize()] is called. ^The memory space used to hold strings |
4572 | ** and BLOBs is freed automatically. Do not pass the pointers returned |
4573 | ** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into |
4574 | ** [sqlite3_free()]. |
4575 | ** |
4576 | ** As long as the input parameters are correct, these routines will only |
4577 | ** fail if an out-of-memory error occurs during a format conversion. |
4578 | ** Only the following subset of interfaces are subject to out-of-memory |
4579 | ** errors: |
4580 | ** |
4581 | ** <ul> |
4582 | ** <li> sqlite3_column_blob() |
4583 | ** <li> sqlite3_column_text() |
4584 | ** <li> sqlite3_column_text16() |
4585 | ** <li> sqlite3_column_bytes() |
4586 | ** <li> sqlite3_column_bytes16() |
4587 | ** </ul> |
4588 | ** |
4589 | ** If an out-of-memory error occurs, then the return value from these |
4590 | ** routines is the same as if the column had contained an SQL NULL value. |
4591 | ** Valid SQL NULL returns can be distinguished from out-of-memory errors |
4592 | ** by invoking the [sqlite3_errcode()] immediately after the suspect |
4593 | ** return value is obtained and before any |
4594 | ** other SQLite interface is called on the same [database connection]. |
4595 | */ |
4596 | SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); |
4597 | SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol); |
4598 | SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol); |
4599 | SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); |
4600 | SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); |
4601 | SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); |
4602 | SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); |
4603 | SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol); |
4604 | SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); |
4605 | SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol); |
4606 | |
4607 | /* |
4608 | ** CAPI3REF: Destroy A Prepared Statement Object |
4609 | ** DESTRUCTOR: sqlite3_stmt |
4610 | ** |
4611 | ** ^The sqlite3_finalize() function is called to delete a [prepared statement]. |
4612 | ** ^If the most recent evaluation of the statement encountered no errors |
4613 | ** or if the statement is never been evaluated, then sqlite3_finalize() returns |
4614 | ** SQLITE_OK. ^If the most recent evaluation of statement S failed, then |
4615 | ** sqlite3_finalize(S) returns the appropriate [error code] or |
4616 | ** [extended error code]. |
4617 | ** |
4618 | ** ^The sqlite3_finalize(S) routine can be called at any point during |
4619 | ** the life cycle of [prepared statement] S: |
4620 | ** before statement S is ever evaluated, after |
4621 | ** one or more calls to [sqlite3_reset()], or after any call |
4622 | ** to [sqlite3_step()] regardless of whether or not the statement has |
4623 | ** completed execution. |
4624 | ** |
4625 | ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op. |
4626 | ** |
4627 | ** The application must finalize every [prepared statement] in order to avoid |
4628 | ** resource leaks. It is a grievous error for the application to try to use |
4629 | ** a prepared statement after it has been finalized. Any use of a prepared |
4630 | ** statement after it has been finalized can result in undefined and |
4631 | ** undesirable behavior such as segfaults and heap corruption. |
4632 | */ |
4633 | SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt); |
4634 | |
4635 | /* |
4636 | ** CAPI3REF: Reset A Prepared Statement Object |
4637 | ** METHOD: sqlite3_stmt |
4638 | ** |
4639 | ** The sqlite3_reset() function is called to reset a [prepared statement] |
4640 | ** object back to its initial state, ready to be re-executed. |
4641 | ** ^Any SQL statement variables that had values bound to them using |
4642 | ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. |
4643 | ** Use [sqlite3_clear_bindings()] to reset the bindings. |
4644 | ** |
4645 | ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S |
4646 | ** back to the beginning of its program. |
4647 | ** |
4648 | ** ^If the most recent call to [sqlite3_step(S)] for the |
4649 | ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE], |
4650 | ** or if [sqlite3_step(S)] has never before been called on S, |
4651 | ** then [sqlite3_reset(S)] returns [SQLITE_OK]. |
4652 | ** |
4653 | ** ^If the most recent call to [sqlite3_step(S)] for the |
4654 | ** [prepared statement] S indicated an error, then |
4655 | ** [sqlite3_reset(S)] returns an appropriate [error code]. |
4656 | ** |
4657 | ** ^The [sqlite3_reset(S)] interface does not change the values |
4658 | ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. |
4659 | */ |
4660 | SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt); |
4661 | |
4662 | /* |
4663 | ** CAPI3REF: Create Or Redefine SQL Functions |
4664 | ** KEYWORDS: {function creation routines} |
4665 | ** KEYWORDS: {application-defined SQL function} |
4666 | ** KEYWORDS: {application-defined SQL functions} |
4667 | ** METHOD: sqlite3 |
4668 | ** |
4669 | ** ^These functions (collectively known as "function creation routines") |
4670 | ** are used to add SQL functions or aggregates or to redefine the behavior |
4671 | ** of existing SQL functions or aggregates. The only differences between |
4672 | ** the three "sqlite3_create_function*" routines are the text encoding |
4673 | ** expected for the second parameter (the name of the function being |
4674 | ** created) and the presence or absence of a destructor callback for |
4675 | ** the application data pointer. Function sqlite3_create_window_function() |
4676 | ** is similar, but allows the user to supply the extra callback functions |
4677 | ** needed by [aggregate window functions]. |
4678 | ** |
4679 | ** ^The first parameter is the [database connection] to which the SQL |
4680 | ** function is to be added. ^If an application uses more than one database |
4681 | ** connection then application-defined SQL functions must be added |
4682 | ** to each database connection separately. |
4683 | ** |
4684 | ** ^The second parameter is the name of the SQL function to be created or |
4685 | ** redefined. ^The length of the name is limited to 255 bytes in a UTF-8 |
4686 | ** representation, exclusive of the zero-terminator. ^Note that the name |
4687 | ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. |
4688 | ** ^Any attempt to create a function with a longer name |
4689 | ** will result in [SQLITE_MISUSE] being returned. |
4690 | ** |
4691 | ** ^The third parameter (nArg) |
4692 | ** is the number of arguments that the SQL function or |
4693 | ** aggregate takes. ^If this parameter is -1, then the SQL function or |
4694 | ** aggregate may take any number of arguments between 0 and the limit |
4695 | ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third |
4696 | ** parameter is less than -1 or greater than 127 then the behavior is |
4697 | ** undefined. |
4698 | ** |
4699 | ** ^The fourth parameter, eTextRep, specifies what |
4700 | ** [SQLITE_UTF8 | text encoding] this SQL function prefers for |
4701 | ** its parameters. The application should set this parameter to |
4702 | ** [SQLITE_UTF16LE] if the function implementation invokes |
4703 | ** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the |
4704 | ** implementation invokes [sqlite3_value_text16be()] on an input, or |
4705 | ** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8] |
4706 | ** otherwise. ^The same SQL function may be registered multiple times using |
4707 | ** different preferred text encodings, with different implementations for |
4708 | ** each encoding. |
4709 | ** ^When multiple implementations of the same function are available, SQLite |
4710 | ** will pick the one that involves the least amount of data conversion. |
4711 | ** |
4712 | ** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC] |
4713 | ** to signal that the function will always return the same result given |
4714 | ** the same inputs within a single SQL statement. Most SQL functions are |
4715 | ** deterministic. The built-in [random()] SQL function is an example of a |
4716 | ** function that is not deterministic. The SQLite query planner is able to |
4717 | ** perform additional optimizations on deterministic functions, so use |
4718 | ** of the [SQLITE_DETERMINISTIC] flag is recommended where possible. |
4719 | ** |
4720 | ** ^(The fifth parameter is an arbitrary pointer. The implementation of the |
4721 | ** function can gain access to this pointer using [sqlite3_user_data()].)^ |
4722 | ** |
4723 | ** ^The sixth, seventh and eighth parameters passed to the three |
4724 | ** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are |
4725 | ** pointers to C-language functions that implement the SQL function or |
4726 | ** aggregate. ^A scalar SQL function requires an implementation of the xFunc |
4727 | ** callback only; NULL pointers must be passed as the xStep and xFinal |
4728 | ** parameters. ^An aggregate SQL function requires an implementation of xStep |
4729 | ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing |
4730 | ** SQL function or aggregate, pass NULL pointers for all three function |
4731 | ** callbacks. |
4732 | ** |
4733 | ** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue |
4734 | ** and xInverse) passed to sqlite3_create_window_function are pointers to |
4735 | ** C-language callbacks that implement the new function. xStep and xFinal |
4736 | ** must both be non-NULL. xValue and xInverse may either both be NULL, in |
4737 | ** which case a regular aggregate function is created, or must both be |
4738 | ** non-NULL, in which case the new function may be used as either an aggregate |
4739 | ** or aggregate window function. More details regarding the implementation |
4740 | ** of aggregate window functions are |
4741 | ** [user-defined window functions|available here]. |
4742 | ** |
4743 | ** ^(If the final parameter to sqlite3_create_function_v2() or |
4744 | ** sqlite3_create_window_function() is not NULL, then it is destructor for |
4745 | ** the application data pointer. The destructor is invoked when the function |
4746 | ** is deleted, either by being overloaded or when the database connection |
4747 | ** closes.)^ ^The destructor is also invoked if the call to |
4748 | ** sqlite3_create_function_v2() fails. ^When the destructor callback is |
4749 | ** invoked, it is passed a single argument which is a copy of the application |
4750 | ** data pointer which was the fifth parameter to sqlite3_create_function_v2(). |
4751 | ** |
4752 | ** ^It is permitted to register multiple implementations of the same |
4753 | ** functions with the same name but with either differing numbers of |
4754 | ** arguments or differing preferred text encodings. ^SQLite will use |
4755 | ** the implementation that most closely matches the way in which the |
4756 | ** SQL function is used. ^A function implementation with a non-negative |
4757 | ** nArg parameter is a better match than a function implementation with |
4758 | ** a negative nArg. ^A function where the preferred text encoding |
4759 | ** matches the database encoding is a better |
4760 | ** match than a function where the encoding is different. |
4761 | ** ^A function where the encoding difference is between UTF16le and UTF16be |
4762 | ** is a closer match than a function where the encoding difference is |
4763 | ** between UTF8 and UTF16. |
4764 | ** |
4765 | ** ^Built-in functions may be overloaded by new application-defined functions. |
4766 | ** |
4767 | ** ^An application-defined function is permitted to call other |
4768 | ** SQLite interfaces. However, such calls must not |
4769 | ** close the database connection nor finalize or reset the prepared |
4770 | ** statement in which the function is running. |
4771 | */ |
4772 | SQLITE_API int sqlite3_create_function( |
4773 | sqlite3 *db, |
4774 | const char *zFunctionName, |
4775 | int nArg, |
4776 | int eTextRep, |
4777 | void *pApp, |
4778 | void (*xFunc)(sqlite3_context*,int,sqlite3_value**), |
4779 | void (*xStep)(sqlite3_context*,int,sqlite3_value**), |
4780 | void (*xFinal)(sqlite3_context*) |
4781 | ); |
4782 | SQLITE_API int sqlite3_create_function16( |
4783 | sqlite3 *db, |
4784 | const void *zFunctionName, |
4785 | int nArg, |
4786 | int eTextRep, |
4787 | void *pApp, |
4788 | void (*xFunc)(sqlite3_context*,int,sqlite3_value**), |
4789 | void (*xStep)(sqlite3_context*,int,sqlite3_value**), |
4790 | void (*xFinal)(sqlite3_context*) |
4791 | ); |
4792 | SQLITE_API int sqlite3_create_function_v2( |
4793 | sqlite3 *db, |
4794 | const char *zFunctionName, |
4795 | int nArg, |
4796 | int eTextRep, |
4797 | void *pApp, |
4798 | void (*xFunc)(sqlite3_context*,int,sqlite3_value**), |
4799 | void (*xStep)(sqlite3_context*,int,sqlite3_value**), |
4800 | void (*xFinal)(sqlite3_context*), |
4801 | void(*xDestroy)(void*) |
4802 | ); |
4803 | SQLITE_API int sqlite3_create_window_function( |
4804 | sqlite3 *db, |
4805 | const char *zFunctionName, |
4806 | int nArg, |
4807 | int eTextRep, |
4808 | void *pApp, |
4809 | void (*xStep)(sqlite3_context*,int,sqlite3_value**), |
4810 | void (*xFinal)(sqlite3_context*), |
4811 | void (*xValue)(sqlite3_context*), |
4812 | void (*xInverse)(sqlite3_context*,int,sqlite3_value**), |
4813 | void(*xDestroy)(void*) |
4814 | ); |
4815 | |
4816 | /* |
4817 | ** CAPI3REF: Text Encodings |
4818 | ** |
4819 | ** These constant define integer codes that represent the various |
4820 | ** text encodings supported by SQLite. |
4821 | */ |
4822 | #define SQLITE_UTF8 1 /* IMP: R-37514-35566 */ |
4823 | #define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */ |
4824 | #define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */ |
4825 | #define SQLITE_UTF16 4 /* Use native byte order */ |
4826 | #define SQLITE_ANY 5 /* Deprecated */ |
4827 | #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ |
4828 | |
4829 | /* |
4830 | ** CAPI3REF: Function Flags |
4831 | ** |
4832 | ** These constants may be ORed together with the |
4833 | ** [SQLITE_UTF8 | preferred text encoding] as the fourth argument |
4834 | ** to [sqlite3_create_function()], [sqlite3_create_function16()], or |
4835 | ** [sqlite3_create_function_v2()]. |
4836 | */ |
4837 | #define SQLITE_DETERMINISTIC 0x800 |
4838 | |
4839 | /* |
4840 | ** CAPI3REF: Deprecated Functions |
4841 | ** DEPRECATED |
4842 | ** |
4843 | ** These functions are [deprecated]. In order to maintain |
4844 | ** backwards compatibility with older code, these functions continue |
4845 | ** to be supported. However, new applications should avoid |
4846 | ** the use of these functions. To encourage programmers to avoid |
4847 | ** these functions, we will not explain what they do. |
4848 | */ |
4849 | #ifndef SQLITE_OMIT_DEPRECATED |
4850 | SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); |
4851 | SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); |
4852 | SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); |
4853 | SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void); |
4854 | SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); |
4855 | SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int), |
4856 | void*,sqlite3_int64); |
4857 | #endif |
4858 | |
4859 | /* |
4860 | ** CAPI3REF: Obtaining SQL Values |
4861 | ** METHOD: sqlite3_value |
4862 | ** |
4863 | ** <b>Summary:</b> |
4864 | ** <blockquote><table border=0 cellpadding=0 cellspacing=0> |
4865 | ** <tr><td><b>sqlite3_value_blob</b><td>→<td>BLOB value |
4866 | ** <tr><td><b>sqlite3_value_double</b><td>→<td>REAL value |
4867 | ** <tr><td><b>sqlite3_value_int</b><td>→<td>32-bit INTEGER value |
4868 | ** <tr><td><b>sqlite3_value_int64</b><td>→<td>64-bit INTEGER value |
4869 | ** <tr><td><b>sqlite3_value_pointer</b><td>→<td>Pointer value |
4870 | ** <tr><td><b>sqlite3_value_text</b><td>→<td>UTF-8 TEXT value |
4871 | ** <tr><td><b>sqlite3_value_text16</b><td>→<td>UTF-16 TEXT value in |
4872 | ** the native byteorder |
4873 | ** <tr><td><b>sqlite3_value_text16be</b><td>→<td>UTF-16be TEXT value |
4874 | ** <tr><td><b>sqlite3_value_text16le</b><td>→<td>UTF-16le TEXT value |
4875 | ** <tr><td> <td> <td> |
4876 | ** <tr><td><b>sqlite3_value_bytes</b><td>→<td>Size of a BLOB |
4877 | ** or a UTF-8 TEXT in bytes |
4878 | ** <tr><td><b>sqlite3_value_bytes16 </b> |
4879 | ** <td>→ <td>Size of UTF-16 |
4880 | ** TEXT in bytes |
4881 | ** <tr><td><b>sqlite3_value_type</b><td>→<td>Default |
4882 | ** datatype of the value |
4883 | ** <tr><td><b>sqlite3_value_numeric_type </b> |
4884 | ** <td>→ <td>Best numeric datatype of the value |
4885 | ** <tr><td><b>sqlite3_value_nochange </b> |
4886 | ** <td>→ <td>True if the column is unchanged in an UPDATE |
4887 | ** against a virtual table. |
4888 | ** </table></blockquote> |
4889 | ** |
4890 | ** <b>Details:</b> |
4891 | ** |
4892 | ** These routines extract type, size, and content information from |
4893 | ** [protected sqlite3_value] objects. Protected sqlite3_value objects |
4894 | ** are used to pass parameter information into implementation of |
4895 | ** [application-defined SQL functions] and [virtual tables]. |
4896 | ** |
4897 | ** These routines work only with [protected sqlite3_value] objects. |
4898 | ** Any attempt to use these routines on an [unprotected sqlite3_value] |
4899 | ** is not threadsafe. |
4900 | ** |
4901 | ** ^These routines work just like the corresponding [column access functions] |
4902 | ** except that these routines take a single [protected sqlite3_value] object |
4903 | ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. |
4904 | ** |
4905 | ** ^The sqlite3_value_text16() interface extracts a UTF-16 string |
4906 | ** in the native byte-order of the host machine. ^The |
4907 | ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces |
4908 | ** extract UTF-16 strings as big-endian and little-endian respectively. |
4909 | ** |
4910 | ** ^If [sqlite3_value] object V was initialized |
4911 | ** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)] |
4912 | ** and if X and Y are strings that compare equal according to strcmp(X,Y), |
4913 | ** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise, |
4914 | ** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer() |
4915 | ** routine is part of the [pointer passing interface] added for SQLite 3.20.0. |
4916 | ** |
4917 | ** ^(The sqlite3_value_type(V) interface returns the |
4918 | ** [SQLITE_INTEGER | datatype code] for the initial datatype of the |
4919 | ** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER], |
4920 | ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^ |
4921 | ** Other interfaces might change the datatype for an sqlite3_value object. |
4922 | ** For example, if the datatype is initially SQLITE_INTEGER and |
4923 | ** sqlite3_value_text(V) is called to extract a text value for that |
4924 | ** integer, then subsequent calls to sqlite3_value_type(V) might return |
4925 | ** SQLITE_TEXT. Whether or not a persistent internal datatype conversion |
4926 | ** occurs is undefined and may change from one release of SQLite to the next. |
4927 | ** |
4928 | ** ^(The sqlite3_value_numeric_type() interface attempts to apply |
4929 | ** numeric affinity to the value. This means that an attempt is |
4930 | ** made to convert the value to an integer or floating point. If |
4931 | ** such a conversion is possible without loss of information (in other |
4932 | ** words, if the value is a string that looks like a number) |
4933 | ** then the conversion is performed. Otherwise no conversion occurs. |
4934 | ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^ |
4935 | ** |
4936 | ** ^Within the [xUpdate] method of a [virtual table], the |
4937 | ** sqlite3_value_nochange(X) interface returns true if and only if |
4938 | ** the column corresponding to X is unchanged by the UPDATE operation |
4939 | ** that the xUpdate method call was invoked to implement and if |
4940 | ** and the prior [xColumn] method call that was invoked to extracted |
4941 | ** the value for that column returned without setting a result (probably |
4942 | ** because it queried [sqlite3_vtab_nochange()] and found that the column |
4943 | ** was unchanging). ^Within an [xUpdate] method, any value for which |
4944 | ** sqlite3_value_nochange(X) is true will in all other respects appear |
4945 | ** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other |
4946 | ** than within an [xUpdate] method call for an UPDATE statement, then |
4947 | ** the return value is arbitrary and meaningless. |
4948 | ** |
4949 | ** Please pay particular attention to the fact that the pointer returned |
4950 | ** from [sqlite3_value_blob()], [sqlite3_value_text()], or |
4951 | ** [sqlite3_value_text16()] can be invalidated by a subsequent call to |
4952 | ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], |
4953 | ** or [sqlite3_value_text16()]. |
4954 | ** |
4955 | ** These routines must be called from the same thread as |
4956 | ** the SQL function that supplied the [sqlite3_value*] parameters. |
4957 | ** |
4958 | ** As long as the input parameter is correct, these routines can only |
4959 | ** fail if an out-of-memory error occurs during a format conversion. |
4960 | ** Only the following subset of interfaces are subject to out-of-memory |
4961 | ** errors: |
4962 | ** |
4963 | ** <ul> |
4964 | ** <li> sqlite3_value_blob() |
4965 | ** <li> sqlite3_value_text() |
4966 | ** <li> sqlite3_value_text16() |
4967 | ** <li> sqlite3_value_text16le() |
4968 | ** <li> sqlite3_value_text16be() |
4969 | ** <li> sqlite3_value_bytes() |
4970 | ** <li> sqlite3_value_bytes16() |
4971 | ** </ul> |
4972 | ** |
4973 | ** If an out-of-memory error occurs, then the return value from these |
4974 | ** routines is the same as if the column had contained an SQL NULL value. |
4975 | ** Valid SQL NULL returns can be distinguished from out-of-memory errors |
4976 | ** by invoking the [sqlite3_errcode()] immediately after the suspect |
4977 | ** return value is obtained and before any |
4978 | ** other SQLite interface is called on the same [database connection]. |
4979 | */ |
4980 | SQLITE_API const void *sqlite3_value_blob(sqlite3_value*); |
4981 | SQLITE_API double sqlite3_value_double(sqlite3_value*); |
4982 | SQLITE_API int sqlite3_value_int(sqlite3_value*); |
4983 | SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*); |
4984 | SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*); |
4985 | SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*); |
4986 | SQLITE_API const void *sqlite3_value_text16(sqlite3_value*); |
4987 | SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*); |
4988 | SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*); |
4989 | SQLITE_API int sqlite3_value_bytes(sqlite3_value*); |
4990 | SQLITE_API int sqlite3_value_bytes16(sqlite3_value*); |
4991 | SQLITE_API int sqlite3_value_type(sqlite3_value*); |
4992 | SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*); |
4993 | SQLITE_API int sqlite3_value_nochange(sqlite3_value*); |
4994 | |
4995 | /* |
4996 | ** CAPI3REF: Finding The Subtype Of SQL Values |
4997 | ** METHOD: sqlite3_value |
4998 | ** |
4999 | ** The sqlite3_value_subtype(V) function returns the subtype for |
5000 | ** an [application-defined SQL function] argument V. The subtype |
5001 | ** information can be used to pass a limited amount of context from |
5002 | ** one SQL function to another. Use the [sqlite3_result_subtype()] |
5003 | ** routine to set the subtype for the return value of an SQL function. |
5004 | */ |
5005 | SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*); |
5006 | |
5007 | /* |
5008 | ** CAPI3REF: Copy And Free SQL Values |
5009 | ** METHOD: sqlite3_value |
5010 | ** |
5011 | ** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value] |
5012 | ** object D and returns a pointer to that copy. ^The [sqlite3_value] returned |
5013 | ** is a [protected sqlite3_value] object even if the input is not. |
5014 | ** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a |
5015 | ** memory allocation fails. |
5016 | ** |
5017 | ** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object |
5018 | ** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer |
5019 | ** then sqlite3_value_free(V) is a harmless no-op. |
5020 | */ |
5021 | SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*); |
5022 | SQLITE_API void sqlite3_value_free(sqlite3_value*); |
5023 | |
5024 | /* |
5025 | ** CAPI3REF: Obtain Aggregate Function Context |
5026 | ** METHOD: sqlite3_context |
5027 | ** |
5028 | ** Implementations of aggregate SQL functions use this |
5029 | ** routine to allocate memory for storing their state. |
5030 | ** |
5031 | ** ^The first time the sqlite3_aggregate_context(C,N) routine is called |
5032 | ** for a particular aggregate function, SQLite |
5033 | ** allocates N of memory, zeroes out that memory, and returns a pointer |
5034 | ** to the new memory. ^On second and subsequent calls to |
5035 | ** sqlite3_aggregate_context() for the same aggregate function instance, |
5036 | ** the same buffer is returned. Sqlite3_aggregate_context() is normally |
5037 | ** called once for each invocation of the xStep callback and then one |
5038 | ** last time when the xFinal callback is invoked. ^(When no rows match |
5039 | ** an aggregate query, the xStep() callback of the aggregate function |
5040 | ** implementation is never called and xFinal() is called exactly once. |
5041 | ** In those cases, sqlite3_aggregate_context() might be called for the |
5042 | ** first time from within xFinal().)^ |
5043 | ** |
5044 | ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer |
5045 | ** when first called if N is less than or equal to zero or if a memory |
5046 | ** allocate error occurs. |
5047 | ** |
5048 | ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is |
5049 | ** determined by the N parameter on first successful call. Changing the |
5050 | ** value of N in subsequent call to sqlite3_aggregate_context() within |
5051 | ** the same aggregate function instance will not resize the memory |
5052 | ** allocation.)^ Within the xFinal callback, it is customary to set |
5053 | ** N=0 in calls to sqlite3_aggregate_context(C,N) so that no |
5054 | ** pointless memory allocations occur. |
5055 | ** |
5056 | ** ^SQLite automatically frees the memory allocated by |
5057 | ** sqlite3_aggregate_context() when the aggregate query concludes. |
5058 | ** |
5059 | ** The first parameter must be a copy of the |
5060 | ** [sqlite3_context | SQL function context] that is the first parameter |
5061 | ** to the xStep or xFinal callback routine that implements the aggregate |
5062 | ** function. |
5063 | ** |
5064 | ** This routine must be called from the same thread in which |
5065 | ** the aggregate SQL function is running. |
5066 | */ |
5067 | SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); |
5068 | |
5069 | /* |
5070 | ** CAPI3REF: User Data For Functions |
5071 | ** METHOD: sqlite3_context |
5072 | ** |
5073 | ** ^The sqlite3_user_data() interface returns a copy of |
5074 | ** the pointer that was the pUserData parameter (the 5th parameter) |
5075 | ** of the [sqlite3_create_function()] |
5076 | ** and [sqlite3_create_function16()] routines that originally |
5077 | ** registered the application defined function. |
5078 | ** |
5079 | ** This routine must be called from the same thread in which |
5080 | ** the application-defined function is running. |
5081 | */ |
5082 | SQLITE_API void *sqlite3_user_data(sqlite3_context*); |
5083 | |
5084 | /* |
5085 | ** CAPI3REF: Database Connection For Functions |
5086 | ** METHOD: sqlite3_context |
5087 | ** |
5088 | ** ^The sqlite3_context_db_handle() interface returns a copy of |
5089 | ** the pointer to the [database connection] (the 1st parameter) |
5090 | ** of the [sqlite3_create_function()] |
5091 | ** and [sqlite3_create_function16()] routines that originally |
5092 | ** registered the application defined function. |
5093 | */ |
5094 | SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*); |
5095 | |
5096 | /* |
5097 | ** CAPI3REF: Function Auxiliary Data |
5098 | ** METHOD: sqlite3_context |
5099 | ** |
5100 | ** These functions may be used by (non-aggregate) SQL functions to |
5101 | ** associate metadata with argument values. If the same value is passed to |
5102 | ** multiple invocations of the same SQL function during query execution, under |
5103 | ** some circumstances the associated metadata may be preserved. An example |
5104 | ** of where this might be useful is in a regular-expression matching |
5105 | ** function. The compiled version of the regular expression can be stored as |
5106 | ** metadata associated with the pattern string. |
5107 | ** Then as long as the pattern string remains the same, |
5108 | ** the compiled regular expression can be reused on multiple |
5109 | ** invocations of the same function. |
5110 | ** |
5111 | ** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata |
5112 | ** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument |
5113 | ** value to the application-defined function. ^N is zero for the left-most |
5114 | ** function argument. ^If there is no metadata |
5115 | ** associated with the function argument, the sqlite3_get_auxdata(C,N) interface |
5116 | ** returns a NULL pointer. |
5117 | ** |
5118 | ** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th |
5119 | ** argument of the application-defined function. ^Subsequent |
5120 | ** calls to sqlite3_get_auxdata(C,N) return P from the most recent |
5121 | ** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or |
5122 | ** NULL if the metadata has been discarded. |
5123 | ** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL, |
5124 | ** SQLite will invoke the destructor function X with parameter P exactly |
5125 | ** once, when the metadata is discarded. |
5126 | ** SQLite is free to discard the metadata at any time, including: <ul> |
5127 | ** <li> ^(when the corresponding function parameter changes)^, or |
5128 | ** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the |
5129 | ** SQL statement)^, or |
5130 | ** <li> ^(when sqlite3_set_auxdata() is invoked again on the same |
5131 | ** parameter)^, or |
5132 | ** <li> ^(during the original sqlite3_set_auxdata() call when a memory |
5133 | ** allocation error occurs.)^ </ul> |
5134 | ** |
5135 | ** Note the last bullet in particular. The destructor X in |
5136 | ** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the |
5137 | ** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata() |
5138 | ** should be called near the end of the function implementation and the |
5139 | ** function implementation should not make any use of P after |
5140 | ** sqlite3_set_auxdata() has been called. |
5141 | ** |
5142 | ** ^(In practice, metadata is preserved between function calls for |
5143 | ** function parameters that are compile-time constants, including literal |
5144 | ** values and [parameters] and expressions composed from the same.)^ |
5145 | ** |
5146 | ** The value of the N parameter to these interfaces should be non-negative. |
5147 | ** Future enhancements may make use of negative N values to define new |
5148 | ** kinds of function caching behavior. |
5149 | ** |
5150 | ** These routines must be called from the same thread in which |
5151 | ** the SQL function is running. |
5152 | */ |
5153 | SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N); |
5154 | SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); |
5155 | |
5156 | |
5157 | /* |
5158 | ** CAPI3REF: Constants Defining Special Destructor Behavior |
5159 | ** |
5160 | ** These are special values for the destructor that is passed in as the |
5161 | ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor |
5162 | ** argument is SQLITE_STATIC, it means that the content pointer is constant |
5163 | ** and will never change. It does not need to be destroyed. ^The |
5164 | ** SQLITE_TRANSIENT value means that the content will likely change in |
5165 | ** the near future and that SQLite should make its own private copy of |
5166 | ** the content before returning. |
5167 | ** |
5168 | ** The typedef is necessary to work around problems in certain |
5169 | ** C++ compilers. |
5170 | */ |
5171 | typedef void (*sqlite3_destructor_type)(void*); |
5172 | #define SQLITE_STATIC ((sqlite3_destructor_type)0) |
5173 | #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) |
5174 | |
5175 | /* |
5176 | ** CAPI3REF: Setting The Result Of An SQL Function |
5177 | ** METHOD: sqlite3_context |
5178 | ** |
5179 | ** These routines are used by the xFunc or xFinal callbacks that |
5180 | ** implement SQL functions and aggregates. See |
5181 | ** [sqlite3_create_function()] and [sqlite3_create_function16()] |
5182 | ** for additional information. |
5183 | ** |
5184 | ** These functions work very much like the [parameter binding] family of |
5185 | ** functions used to bind values to host parameters in prepared statements. |
5186 | ** Refer to the [SQL parameter] documentation for additional information. |
5187 | ** |
5188 | ** ^The sqlite3_result_blob() interface sets the result from |
5189 | ** an application-defined function to be the BLOB whose content is pointed |
5190 | ** to by the second parameter and which is N bytes long where N is the |
5191 | ** third parameter. |
5192 | ** |
5193 | ** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N) |
5194 | ** interfaces set the result of the application-defined function to be |
5195 | ** a BLOB containing all zero bytes and N bytes in size. |
5196 | ** |
5197 | ** ^The sqlite3_result_double() interface sets the result from |
5198 | ** an application-defined function to be a floating point value specified |
5199 | ** by its 2nd argument. |
5200 | ** |
5201 | ** ^The sqlite3_result_error() and sqlite3_result_error16() functions |
5202 | ** cause the implemented SQL function to throw an exception. |
5203 | ** ^SQLite uses the string pointed to by the |
5204 | ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() |
5205 | ** as the text of an error message. ^SQLite interprets the error |
5206 | ** message string from sqlite3_result_error() as UTF-8. ^SQLite |
5207 | ** interprets the string from sqlite3_result_error16() as UTF-16 in native |
5208 | ** byte order. ^If the third parameter to sqlite3_result_error() |
5209 | ** or sqlite3_result_error16() is negative then SQLite takes as the error |
5210 | ** message all text up through the first zero character. |
5211 | ** ^If the third parameter to sqlite3_result_error() or |
5212 | ** sqlite3_result_error16() is non-negative then SQLite takes that many |
5213 | ** bytes (not characters) from the 2nd parameter as the error message. |
5214 | ** ^The sqlite3_result_error() and sqlite3_result_error16() |
5215 | ** routines make a private copy of the error message text before |
5216 | ** they return. Hence, the calling function can deallocate or |
5217 | ** modify the text after they return without harm. |
5218 | ** ^The sqlite3_result_error_code() function changes the error code |
5219 | ** returned by SQLite as a result of an error in a function. ^By default, |
5220 | ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error() |
5221 | ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. |
5222 | ** |
5223 | ** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an |
5224 | ** error indicating that a string or BLOB is too long to represent. |
5225 | ** |
5226 | ** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an |
5227 | ** error indicating that a memory allocation failed. |
5228 | ** |
5229 | ** ^The sqlite3_result_int() interface sets the return value |
5230 | ** of the application-defined function to be the 32-bit signed integer |
5231 | ** value given in the 2nd argument. |
5232 | ** ^The sqlite3_result_int64() interface sets the return value |
5233 | ** of the application-defined function to be the 64-bit signed integer |
5234 | ** value given in the 2nd argument. |
5235 | ** |
5236 | ** ^The sqlite3_result_null() interface sets the return value |
5237 | ** of the application-defined function to be NULL. |
5238 | ** |
5239 | ** ^The sqlite3_result_text(), sqlite3_result_text16(), |
5240 | ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces |
5241 | ** set the return value of the application-defined function to be |
5242 | ** a text string which is represented as UTF-8, UTF-16 native byte order, |
5243 | ** UTF-16 little endian, or UTF-16 big endian, respectively. |
5244 | ** ^The sqlite3_result_text64() interface sets the return value of an |
5245 | ** application-defined function to be a text string in an encoding |
5246 | ** specified by the fifth (and last) parameter, which must be one |
5247 | ** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]. |
5248 | ** ^SQLite takes the text result from the application from |
5249 | ** the 2nd parameter of the sqlite3_result_text* interfaces. |
5250 | ** ^If the 3rd parameter to the sqlite3_result_text* interfaces |
5251 | ** is negative, then SQLite takes result text from the 2nd parameter |
5252 | ** through the first zero character. |
5253 | ** ^If the 3rd parameter to the sqlite3_result_text* interfaces |
5254 | ** is non-negative, then as many bytes (not characters) of the text |
5255 | ** pointed to by the 2nd parameter are taken as the application-defined |
5256 | ** function result. If the 3rd parameter is non-negative, then it |
5257 | ** must be the byte offset into the string where the NUL terminator would |
5258 | ** appear if the string where NUL terminated. If any NUL characters occur |
5259 | ** in the string at a byte offset that is less than the value of the 3rd |
5260 | ** parameter, then the resulting string will contain embedded NULs and the |
5261 | ** result of expressions operating on strings with embedded NULs is undefined. |
5262 | ** ^If the 4th parameter to the sqlite3_result_text* interfaces |
5263 | ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that |
5264 | ** function as the destructor on the text or BLOB result when it has |
5265 | ** finished using that result. |
5266 | ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to |
5267 | ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite |
5268 | ** assumes that the text or BLOB result is in constant space and does not |
5269 | ** copy the content of the parameter nor call a destructor on the content |
5270 | ** when it has finished using that result. |
5271 | ** ^If the 4th parameter to the sqlite3_result_text* interfaces |
5272 | ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT |
5273 | ** then SQLite makes a copy of the result into space obtained |
5274 | ** from [sqlite3_malloc()] before it returns. |
5275 | ** |
5276 | ** ^The sqlite3_result_value() interface sets the result of |
5277 | ** the application-defined function to be a copy of the |
5278 | ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The |
5279 | ** sqlite3_result_value() interface makes a copy of the [sqlite3_value] |
5280 | ** so that the [sqlite3_value] specified in the parameter may change or |
5281 | ** be deallocated after sqlite3_result_value() returns without harm. |
5282 | ** ^A [protected sqlite3_value] object may always be used where an |
5283 | ** [unprotected sqlite3_value] object is required, so either |
5284 | ** kind of [sqlite3_value] object can be used with this interface. |
5285 | ** |
5286 | ** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an |
5287 | ** SQL NULL value, just like [sqlite3_result_null(C)], except that it |
5288 | ** also associates the host-language pointer P or type T with that |
5289 | ** NULL value such that the pointer can be retrieved within an |
5290 | ** [application-defined SQL function] using [sqlite3_value_pointer()]. |
5291 | ** ^If the D parameter is not NULL, then it is a pointer to a destructor |
5292 | ** for the P parameter. ^SQLite invokes D with P as its only argument |
5293 | ** when SQLite is finished with P. The T parameter should be a static |
5294 | ** string and preferably a string literal. The sqlite3_result_pointer() |
5295 | ** routine is part of the [pointer passing interface] added for SQLite 3.20.0. |
5296 | ** |
5297 | ** If these routines are called from within the different thread |
5298 | ** than the one containing the application-defined function that received |
5299 | ** the [sqlite3_context] pointer, the results are undefined. |
5300 | */ |
5301 | SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); |
5302 | SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*, |
5303 | sqlite3_uint64,void(*)(void*)); |
5304 | SQLITE_API void sqlite3_result_double(sqlite3_context*, double); |
5305 | SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int); |
5306 | SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int); |
5307 | SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*); |
5308 | SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*); |
5309 | SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int); |
5310 | SQLITE_API void sqlite3_result_int(sqlite3_context*, int); |
5311 | SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); |
5312 | SQLITE_API void sqlite3_result_null(sqlite3_context*); |
5313 | SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); |
5314 | SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64, |
5315 | void(*)(void*), unsigned char encoding); |
5316 | SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); |
5317 | SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); |
5318 | SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); |
5319 | SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*); |
5320 | SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*)); |
5321 | SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n); |
5322 | SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n); |
5323 | |
5324 | |
5325 | /* |
5326 | ** CAPI3REF: Setting The Subtype Of An SQL Function |
5327 | ** METHOD: sqlite3_context |
5328 | ** |
5329 | ** The sqlite3_result_subtype(C,T) function causes the subtype of |
5330 | ** the result from the [application-defined SQL function] with |
5331 | ** [sqlite3_context] C to be the value T. Only the lower 8 bits |
5332 | ** of the subtype T are preserved in current versions of SQLite; |
5333 | ** higher order bits are discarded. |
5334 | ** The number of subtype bytes preserved by SQLite might increase |
5335 | ** in future releases of SQLite. |
5336 | */ |
5337 | SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int); |
5338 | |
5339 | /* |
5340 | ** CAPI3REF: Define New Collating Sequences |
5341 | ** METHOD: sqlite3 |
5342 | ** |
5343 | ** ^These functions add, remove, or modify a [collation] associated |
5344 | ** with the [database connection] specified as the first argument. |
5345 | ** |
5346 | ** ^The name of the collation is a UTF-8 string |
5347 | ** for sqlite3_create_collation() and sqlite3_create_collation_v2() |
5348 | ** and a UTF-16 string in native byte order for sqlite3_create_collation16(). |
5349 | ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are |
5350 | ** considered to be the same name. |
5351 | ** |
5352 | ** ^(The third argument (eTextRep) must be one of the constants: |
5353 | ** <ul> |
5354 | ** <li> [SQLITE_UTF8], |
5355 | ** <li> [SQLITE_UTF16LE], |
5356 | ** <li> [SQLITE_UTF16BE], |
5357 | ** <li> [SQLITE_UTF16], or |
5358 | ** <li> [SQLITE_UTF16_ALIGNED]. |
5359 | ** </ul>)^ |
5360 | ** ^The eTextRep argument determines the encoding of strings passed |
5361 | ** to the collating function callback, xCallback. |
5362 | ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep |
5363 | ** force strings to be UTF16 with native byte order. |
5364 | ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin |
5365 | ** on an even byte address. |
5366 | ** |
5367 | ** ^The fourth argument, pArg, is an application data pointer that is passed |
5368 | ** through as the first argument to the collating function callback. |
5369 | ** |
5370 | ** ^The fifth argument, xCallback, is a pointer to the collating function. |
5371 | ** ^Multiple collating functions can be registered using the same name but |
5372 | ** with different eTextRep parameters and SQLite will use whichever |
5373 | ** function requires the least amount of data transformation. |
5374 | ** ^If the xCallback argument is NULL then the collating function is |
5375 | ** deleted. ^When all collating functions having the same name are deleted, |
5376 | ** that collation is no longer usable. |
5377 | ** |
5378 | ** ^The collating function callback is invoked with a copy of the pArg |
5379 | ** application data pointer and with two strings in the encoding specified |
5380 | ** by the eTextRep argument. The collating function must return an |
5381 | ** integer that is negative, zero, or positive |
5382 | ** if the first string is less than, equal to, or greater than the second, |
5383 | ** respectively. A collating function must always return the same answer |
5384 | ** given the same inputs. If two or more collating functions are registered |
5385 | ** to the same collation name (using different eTextRep values) then all |
5386 | ** must give an equivalent answer when invoked with equivalent strings. |
5387 | ** The collating function must obey the following properties for all |
5388 | ** strings A, B, and C: |
5389 | ** |
5390 | ** <ol> |
5391 | ** <li> If A==B then B==A. |
5392 | ** <li> If A==B and B==C then A==C. |
5393 | ** <li> If A<B THEN B>A. |
5394 | ** <li> If A<B and B<C then A<C. |
5395 | ** </ol> |
5396 | ** |
5397 | ** If a collating function fails any of the above constraints and that |
5398 | ** collating function is registered and used, then the behavior of SQLite |
5399 | ** is undefined. |
5400 | ** |
5401 | ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation() |
5402 | ** with the addition that the xDestroy callback is invoked on pArg when |
5403 | ** the collating function is deleted. |
5404 | ** ^Collating functions are deleted when they are overridden by later |
5405 | ** calls to the collation creation functions or when the |
5406 | ** [database connection] is closed using [sqlite3_close()]. |
5407 | ** |
5408 | ** ^The xDestroy callback is <u>not</u> called if the |
5409 | ** sqlite3_create_collation_v2() function fails. Applications that invoke |
5410 | ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should |
5411 | ** check the return code and dispose of the application data pointer |
5412 | ** themselves rather than expecting SQLite to deal with it for them. |
5413 | ** This is different from every other SQLite interface. The inconsistency |
5414 | ** is unfortunate but cannot be changed without breaking backwards |
5415 | ** compatibility. |
5416 | ** |
5417 | ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. |
5418 | */ |
5419 | SQLITE_API int sqlite3_create_collation( |
5420 | sqlite3*, |
5421 | const char *zName, |
5422 | int eTextRep, |
5423 | void *pArg, |
5424 | int(*xCompare)(void*,int,const void*,int,const void*) |
5425 | ); |
5426 | SQLITE_API int sqlite3_create_collation_v2( |
5427 | sqlite3*, |
5428 | const char *zName, |
5429 | int eTextRep, |
5430 | void *pArg, |
5431 | int(*xCompare)(void*,int,const void*,int,const void*), |
5432 | void(*xDestroy)(void*) |
5433 | ); |
5434 | SQLITE_API int sqlite3_create_collation16( |
5435 | sqlite3*, |
5436 | const void *zName, |
5437 | int eTextRep, |
5438 | void *pArg, |
5439 | int(*xCompare)(void*,int,const void*,int,const void*) |
5440 | ); |
5441 | |
5442 | /* |
5443 | ** CAPI3REF: Collation Needed Callbacks |
5444 | ** METHOD: sqlite3 |
5445 | ** |
5446 | ** ^To avoid having to register all collation sequences before a database |
5447 | ** can be used, a single callback function may be registered with the |
5448 | ** [database connection] to be invoked whenever an undefined collation |
5449 | ** sequence is required. |
5450 | ** |
5451 | ** ^If the function is registered using the sqlite3_collation_needed() API, |
5452 | ** then it is passed the names of undefined collation sequences as strings |
5453 | ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used, |
5454 | ** the names are passed as UTF-16 in machine native byte order. |
5455 | ** ^A call to either function replaces the existing collation-needed callback. |
5456 | ** |
5457 | ** ^(When the callback is invoked, the first argument passed is a copy |
5458 | ** of the second argument to sqlite3_collation_needed() or |
5459 | ** sqlite3_collation_needed16(). The second argument is the database |
5460 | ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], |
5461 | ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation |
5462 | ** sequence function required. The fourth parameter is the name of the |
5463 | ** required collation sequence.)^ |
5464 | ** |
5465 | ** The callback function should register the desired collation using |
5466 | ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or |
5467 | ** [sqlite3_create_collation_v2()]. |
5468 | */ |
5469 | SQLITE_API int sqlite3_collation_needed( |
5470 | sqlite3*, |
5471 | void*, |
5472 | void(*)(void*,sqlite3*,int eTextRep,const char*) |
5473 | ); |
5474 | SQLITE_API int sqlite3_collation_needed16( |
5475 | sqlite3*, |
5476 | void*, |
5477 | void(*)(void*,sqlite3*,int eTextRep,const void*) |
5478 | ); |
5479 | |
5480 | #ifdef SQLITE_HAS_CODEC |
5481 | /* |
5482 | ** Specify the key for an encrypted database. This routine should be |
5483 | ** called right after sqlite3_open(). |
5484 | ** |
5485 | ** The code to implement this API is not available in the public release |
5486 | ** of SQLite. |
5487 | */ |
5488 | SQLITE_API int sqlite3_key( |
5489 | sqlite3 *db, /* Database to be rekeyed */ |
5490 | const void *pKey, int nKey /* The key */ |
5491 | ); |
5492 | SQLITE_API int sqlite3_key_v2( |
5493 | sqlite3 *db, /* Database to be rekeyed */ |
5494 | const char *zDbName, /* Name of the database */ |
5495 | const void *pKey, int nKey /* The key */ |
5496 | ); |
5497 | |
5498 | /* |
5499 | ** Change the key on an open database. If the current database is not |
5500 | ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the |
5501 | ** database is decrypted. |
5502 | ** |
5503 | ** The code to implement this API is not available in the public release |
5504 | ** of SQLite. |
5505 | */ |
5506 | SQLITE_API int sqlite3_rekey( |
5507 | sqlite3 *db, /* Database to be rekeyed */ |
5508 | const void *pKey, int nKey /* The new key */ |
5509 | ); |
5510 | SQLITE_API int sqlite3_rekey_v2( |
5511 | sqlite3 *db, /* Database to be rekeyed */ |
5512 | const char *zDbName, /* Name of the database */ |
5513 | const void *pKey, int nKey /* The new key */ |
5514 | ); |
5515 | |
5516 | /* |
5517 | ** Specify the activation key for a SEE database. Unless |
5518 | ** activated, none of the SEE routines will work. |
5519 | */ |
5520 | SQLITE_API void sqlite3_activate_see( |
5521 | const char *zPassPhrase /* Activation phrase */ |
5522 | ); |
5523 | #endif |
5524 | |
5525 | #ifdef SQLITE_ENABLE_CEROD |
5526 | /* |
5527 | ** Specify the activation key for a CEROD database. Unless |
5528 | ** activated, none of the CEROD routines will work. |
5529 | */ |
5530 | SQLITE_API void sqlite3_activate_cerod( |
5531 | const char *zPassPhrase /* Activation phrase */ |
5532 | ); |
5533 | #endif |
5534 | |
5535 | /* |
5536 | ** CAPI3REF: Suspend Execution For A Short Time |
5537 | ** |
5538 | ** The sqlite3_sleep() function causes the current thread to suspend execution |
5539 | ** for at least a number of milliseconds specified in its parameter. |
5540 | ** |
5541 | ** If the operating system does not support sleep requests with |
5542 | ** millisecond time resolution, then the time will be rounded up to |
5543 | ** the nearest second. The number of milliseconds of sleep actually |
5544 | ** requested from the operating system is returned. |
5545 | ** |
5546 | ** ^SQLite implements this interface by calling the xSleep() |
5547 | ** method of the default [sqlite3_vfs] object. If the xSleep() method |
5548 | ** of the default VFS is not implemented correctly, or not implemented at |
5549 | ** all, then the behavior of sqlite3_sleep() may deviate from the description |
5550 | ** in the previous paragraphs. |
5551 | */ |
5552 | SQLITE_API int sqlite3_sleep(int); |
5553 | |
5554 | /* |
5555 | ** CAPI3REF: Name Of The Folder Holding Temporary Files |
5556 | ** |
5557 | ** ^(If this global variable is made to point to a string which is |
5558 | ** the name of a folder (a.k.a. directory), then all temporary files |
5559 | ** created by SQLite when using a built-in [sqlite3_vfs | VFS] |
5560 | ** will be placed in that directory.)^ ^If this variable |
5561 | ** is a NULL pointer, then SQLite performs a search for an appropriate |
5562 | ** temporary file directory. |
5563 | ** |
5564 | ** Applications are strongly discouraged from using this global variable. |
5565 | ** It is required to set a temporary folder on Windows Runtime (WinRT). |
5566 | ** But for all other platforms, it is highly recommended that applications |
5567 | ** neither read nor write this variable. This global variable is a relic |
5568 | ** that exists for backwards compatibility of legacy applications and should |
5569 | ** be avoided in new projects. |
5570 | ** |
5571 | ** It is not safe to read or modify this variable in more than one |
5572 | ** thread at a time. It is not safe to read or modify this variable |
5573 | ** if a [database connection] is being used at the same time in a separate |
5574 | ** thread. |
5575 | ** It is intended that this variable be set once |
5576 | ** as part of process initialization and before any SQLite interface |
5577 | ** routines have been called and that this variable remain unchanged |
5578 | ** thereafter. |
5579 | ** |
5580 | ** ^The [temp_store_directory pragma] may modify this variable and cause |
5581 | ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, |
5582 | ** the [temp_store_directory pragma] always assumes that any string |
5583 | ** that this variable points to is held in memory obtained from |
5584 | ** [sqlite3_malloc] and the pragma may attempt to free that memory |
5585 | ** using [sqlite3_free]. |
5586 | ** Hence, if this variable is modified directly, either it should be |
5587 | ** made NULL or made to point to memory obtained from [sqlite3_malloc] |
5588 | ** or else the use of the [temp_store_directory pragma] should be avoided. |
5589 | ** Except when requested by the [temp_store_directory pragma], SQLite |
5590 | ** does not free the memory that sqlite3_temp_directory points to. If |
5591 | ** the application wants that memory to be freed, it must do |
5592 | ** so itself, taking care to only do so after all [database connection] |
5593 | ** objects have been destroyed. |
5594 | ** |
5595 | ** <b>Note to Windows Runtime users:</b> The temporary directory must be set |
5596 | ** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various |
5597 | ** features that require the use of temporary files may fail. Here is an |
5598 | ** example of how to do this using C++ with the Windows Runtime: |
5599 | ** |
5600 | ** <blockquote><pre> |
5601 | ** LPCWSTR zPath = Windows::Storage::ApplicationData::Current-> |
5602 | ** TemporaryFolder->Path->Data(); |
5603 | ** char zPathBuf[MAX_PATH + 1]; |
5604 | ** memset(zPathBuf, 0, sizeof(zPathBuf)); |
5605 | ** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf), |
5606 | ** NULL, NULL); |
5607 | ** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf); |
5608 | ** </pre></blockquote> |
5609 | */ |
5610 | SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory; |
5611 | |
5612 | /* |
5613 | ** CAPI3REF: Name Of The Folder Holding Database Files |
5614 | ** |
5615 | ** ^(If this global variable is made to point to a string which is |
5616 | ** the name of a folder (a.k.a. directory), then all database files |
5617 | ** specified with a relative pathname and created or accessed by |
5618 | ** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed |
5619 | ** to be relative to that directory.)^ ^If this variable is a NULL |
5620 | ** pointer, then SQLite assumes that all database files specified |
5621 | ** with a relative pathname are relative to the current directory |
5622 | ** for the process. Only the windows VFS makes use of this global |
5623 | ** variable; it is ignored by the unix VFS. |
5624 | ** |
5625 | ** Changing the value of this variable while a database connection is |
5626 | ** open can result in a corrupt database. |
5627 | ** |
5628 | ** It is not safe to read or modify this variable in more than one |
5629 | ** thread at a time. It is not safe to read or modify this variable |
5630 | ** if a [database connection] is being used at the same time in a separate |
5631 | ** thread. |
5632 | ** It is intended that this variable be set once |
5633 | ** as part of process initialization and before any SQLite interface |
5634 | ** routines have been called and that this variable remain unchanged |
5635 | ** thereafter. |
5636 | ** |
5637 | ** ^The [data_store_directory pragma] may modify this variable and cause |
5638 | ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, |
5639 | ** the [data_store_directory pragma] always assumes that any string |
5640 | ** that this variable points to is held in memory obtained from |
5641 | ** [sqlite3_malloc] and the pragma may attempt to free that memory |
5642 | ** using [sqlite3_free]. |
5643 | ** Hence, if this variable is modified directly, either it should be |
5644 | ** made NULL or made to point to memory obtained from [sqlite3_malloc] |
5645 | ** or else the use of the [data_store_directory pragma] should be avoided. |
5646 | */ |
5647 | SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory; |
5648 | |
5649 | /* |
5650 | ** CAPI3REF: Win32 Specific Interface |
5651 | ** |
5652 | ** These interfaces are available only on Windows. The |
5653 | ** [sqlite3_win32_set_directory] interface is used to set the value associated |
5654 | ** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to |
5655 | ** zValue, depending on the value of the type parameter. The zValue parameter |
5656 | ** should be NULL to cause the previous value to be freed via [sqlite3_free]; |
5657 | ** a non-NULL value will be copied into memory obtained from [sqlite3_malloc] |
5658 | ** prior to being used. The [sqlite3_win32_set_directory] interface returns |
5659 | ** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported, |
5660 | ** or [SQLITE_NOMEM] if memory could not be allocated. The value of the |
5661 | ** [sqlite3_data_directory] variable is intended to act as a replacement for |
5662 | ** the current directory on the sub-platforms of Win32 where that concept is |
5663 | ** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and |
5664 | ** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the |
5665 | ** sqlite3_win32_set_directory interface except the string parameter must be |
5666 | ** UTF-8 or UTF-16, respectively. |
5667 | */ |
5668 | SQLITE_API int sqlite3_win32_set_directory( |
5669 | unsigned long type, /* Identifier for directory being set or reset */ |
5670 | void *zValue /* New value for directory being set or reset */ |
5671 | ); |
5672 | SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue); |
5673 | SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue); |
5674 | |
5675 | /* |
5676 | ** CAPI3REF: Win32 Directory Types |
5677 | ** |
5678 | ** These macros are only available on Windows. They define the allowed values |
5679 | ** for the type argument to the [sqlite3_win32_set_directory] interface. |
5680 | */ |
5681 | #define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1 |
5682 | #define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2 |
5683 | |
5684 | /* |
5685 | ** CAPI3REF: Test For Auto-Commit Mode |
5686 | ** KEYWORDS: {autocommit mode} |
5687 | ** METHOD: sqlite3 |
5688 | ** |
5689 | ** ^The sqlite3_get_autocommit() interface returns non-zero or |
5690 | ** zero if the given database connection is or is not in autocommit mode, |
5691 | ** respectively. ^Autocommit mode is on by default. |
5692 | ** ^Autocommit mode is disabled by a [BEGIN] statement. |
5693 | ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. |
5694 | ** |
5695 | ** If certain kinds of errors occur on a statement within a multi-statement |
5696 | ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], |
5697 | ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the |
5698 | ** transaction might be rolled back automatically. The only way to |
5699 | ** find out whether SQLite automatically rolled back the transaction after |
5700 | ** an error is to use this function. |
5701 | ** |
5702 | ** If another thread changes the autocommit status of the database |
5703 | ** connection while this routine is running, then the return value |
5704 | ** is undefined. |
5705 | */ |
5706 | SQLITE_API int sqlite3_get_autocommit(sqlite3*); |
5707 | |
5708 | /* |
5709 | ** CAPI3REF: Find The Database Handle Of A Prepared Statement |
5710 | ** METHOD: sqlite3_stmt |
5711 | ** |
5712 | ** ^The sqlite3_db_handle interface returns the [database connection] handle |
5713 | ** to which a [prepared statement] belongs. ^The [database connection] |
5714 | ** returned by sqlite3_db_handle is the same [database connection] |
5715 | ** that was the first argument |
5716 | ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to |
5717 | ** create the statement in the first place. |
5718 | */ |
5719 | SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*); |
5720 | |
5721 | /* |
5722 | ** CAPI3REF: Return The Filename For A Database Connection |
5723 | ** METHOD: sqlite3 |
5724 | ** |
5725 | ** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename |
5726 | ** associated with database N of connection D. ^The main database file |
5727 | ** has the name "main". If there is no attached database N on the database |
5728 | ** connection D, or if database N is a temporary or in-memory database, then |
5729 | ** a NULL pointer is returned. |
5730 | ** |
5731 | ** ^The filename returned by this function is the output of the |
5732 | ** xFullPathname method of the [VFS]. ^In other words, the filename |
5733 | ** will be an absolute pathname, even if the filename used |
5734 | ** to open the database originally was a URI or relative pathname. |
5735 | */ |
5736 | SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName); |
5737 | |
5738 | /* |
5739 | ** CAPI3REF: Determine if a database is read-only |
5740 | ** METHOD: sqlite3 |
5741 | ** |
5742 | ** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N |
5743 | ** of connection D is read-only, 0 if it is read/write, or -1 if N is not |
5744 | ** the name of a database on connection D. |
5745 | */ |
5746 | SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName); |
5747 | |
5748 | /* |
5749 | ** CAPI3REF: Find the next prepared statement |
5750 | ** METHOD: sqlite3 |
5751 | ** |
5752 | ** ^This interface returns a pointer to the next [prepared statement] after |
5753 | ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL |
5754 | ** then this interface returns a pointer to the first prepared statement |
5755 | ** associated with the database connection pDb. ^If no prepared statement |
5756 | ** satisfies the conditions of this routine, it returns NULL. |
5757 | ** |
5758 | ** The [database connection] pointer D in a call to |
5759 | ** [sqlite3_next_stmt(D,S)] must refer to an open database |
5760 | ** connection and in particular must not be a NULL pointer. |
5761 | */ |
5762 | SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); |
5763 | |
5764 | /* |
5765 | ** CAPI3REF: Commit And Rollback Notification Callbacks |
5766 | ** METHOD: sqlite3 |
5767 | ** |
5768 | ** ^The sqlite3_commit_hook() interface registers a callback |
5769 | ** function to be invoked whenever a transaction is [COMMIT | committed]. |
5770 | ** ^Any callback set by a previous call to sqlite3_commit_hook() |
5771 | ** for the same database connection is overridden. |
5772 | ** ^The sqlite3_rollback_hook() interface registers a callback |
5773 | ** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. |
5774 | ** ^Any callback set by a previous call to sqlite3_rollback_hook() |
5775 | ** for the same database connection is overridden. |
5776 | ** ^The pArg argument is passed through to the callback. |
5777 | ** ^If the callback on a commit hook function returns non-zero, |
5778 | ** then the commit is converted into a rollback. |
5779 | ** |
5780 | ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions |
5781 | ** return the P argument from the previous call of the same function |
5782 | ** on the same [database connection] D, or NULL for |
5783 | ** the first call for each function on D. |
5784 | ** |
5785 | ** The commit and rollback hook callbacks are not reentrant. |
5786 | ** The callback implementation must not do anything that will modify |
5787 | ** the database connection that invoked the callback. Any actions |
5788 | ** to modify the database connection must be deferred until after the |
5789 | ** completion of the [sqlite3_step()] call that triggered the commit |
5790 | ** or rollback hook in the first place. |
5791 | ** Note that running any other SQL statements, including SELECT statements, |
5792 | ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify |
5793 | ** the database connections for the meaning of "modify" in this paragraph. |
5794 | ** |
5795 | ** ^Registering a NULL function disables the callback. |
5796 | ** |
5797 | ** ^When the commit hook callback routine returns zero, the [COMMIT] |
5798 | ** operation is allowed to continue normally. ^If the commit hook |
5799 | ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. |
5800 | ** ^The rollback hook is invoked on a rollback that results from a commit |
5801 | ** hook returning non-zero, just as it would be with any other rollback. |
5802 | ** |
5803 | ** ^For the purposes of this API, a transaction is said to have been |
5804 | ** rolled back if an explicit "ROLLBACK" statement is executed, or |
5805 | ** an error or constraint causes an implicit rollback to occur. |
5806 | ** ^The rollback callback is not invoked if a transaction is |
5807 | ** automatically rolled back because the database connection is closed. |
5808 | ** |
5809 | ** See also the [sqlite3_update_hook()] interface. |
5810 | */ |
5811 | SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); |
5812 | SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); |
5813 | |
5814 | /* |
5815 | ** CAPI3REF: Data Change Notification Callbacks |
5816 | ** METHOD: sqlite3 |
5817 | ** |
5818 | ** ^The sqlite3_update_hook() interface registers a callback function |
5819 | ** with the [database connection] identified by the first argument |
5820 | ** to be invoked whenever a row is updated, inserted or deleted in |
5821 | ** a [rowid table]. |
5822 | ** ^Any callback set by a previous call to this function |
5823 | ** for the same database connection is overridden. |
5824 | ** |
5825 | ** ^The second argument is a pointer to the function to invoke when a |
5826 | ** row is updated, inserted or deleted in a rowid table. |
5827 | ** ^The first argument to the callback is a copy of the third argument |
5828 | ** to sqlite3_update_hook(). |
5829 | ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], |
5830 | ** or [SQLITE_UPDATE], depending on the operation that caused the callback |
5831 | ** to be invoked. |
5832 | ** ^The third and fourth arguments to the callback contain pointers to the |
5833 | ** database and table name containing the affected row. |
5834 | ** ^The final callback parameter is the [rowid] of the row. |
5835 | ** ^In the case of an update, this is the [rowid] after the update takes place. |
5836 | ** |
5837 | ** ^(The update hook is not invoked when internal system tables are |
5838 | ** modified (i.e. sqlite_master and sqlite_sequence).)^ |
5839 | ** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified. |
5840 | ** |
5841 | ** ^In the current implementation, the update hook |
5842 | ** is not invoked when conflicting rows are deleted because of an |
5843 | ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook |
5844 | ** invoked when rows are deleted using the [truncate optimization]. |
5845 | ** The exceptions defined in this paragraph might change in a future |
5846 | ** release of SQLite. |
5847 | ** |
5848 | ** The update hook implementation must not do anything that will modify |
5849 | ** the database connection that invoked the update hook. Any actions |
5850 | ** to modify the database connection must be deferred until after the |
5851 | ** completion of the [sqlite3_step()] call that triggered the update hook. |
5852 | ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their |
5853 | ** database connections for the meaning of "modify" in this paragraph. |
5854 | ** |
5855 | ** ^The sqlite3_update_hook(D,C,P) function |
5856 | ** returns the P argument from the previous call |
5857 | ** on the same [database connection] D, or NULL for |
5858 | ** the first call on D. |
5859 | ** |
5860 | ** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()], |
5861 | ** and [sqlite3_preupdate_hook()] interfaces. |
5862 | */ |
5863 | SQLITE_API void *sqlite3_update_hook( |
5864 | sqlite3*, |
5865 | void(*)(void *,int ,char const *,char const *,sqlite3_int64), |
5866 | void* |
5867 | ); |
5868 | |
5869 | /* |
5870 | ** CAPI3REF: Enable Or Disable Shared Pager Cache |
5871 | ** |
5872 | ** ^(This routine enables or disables the sharing of the database cache |
5873 | ** and schema data structures between [database connection | connections] |
5874 | ** to the same database. Sharing is enabled if the argument is true |
5875 | ** and disabled if the argument is false.)^ |
5876 | ** |
5877 | ** ^Cache sharing is enabled and disabled for an entire process. |
5878 | ** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]). |
5879 | ** In prior versions of SQLite, |
5880 | ** sharing was enabled or disabled for each thread separately. |
5881 | ** |
5882 | ** ^(The cache sharing mode set by this interface effects all subsequent |
5883 | ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. |
5884 | ** Existing database connections continue use the sharing mode |
5885 | ** that was in effect at the time they were opened.)^ |
5886 | ** |
5887 | ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled |
5888 | ** successfully. An [error code] is returned otherwise.)^ |
5889 | ** |
5890 | ** ^Shared cache is disabled by default. But this might change in |
5891 | ** future releases of SQLite. Applications that care about shared |
5892 | ** cache setting should set it explicitly. |
5893 | ** |
5894 | ** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0 |
5895 | ** and will always return SQLITE_MISUSE. On those systems, |
5896 | ** shared cache mode should be enabled per-database connection via |
5897 | ** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE]. |
5898 | ** |
5899 | ** This interface is threadsafe on processors where writing a |
5900 | ** 32-bit integer is atomic. |
5901 | ** |
5902 | ** See Also: [SQLite Shared-Cache Mode] |
5903 | */ |
5904 | SQLITE_API int sqlite3_enable_shared_cache(int); |
5905 | |
5906 | /* |
5907 | ** CAPI3REF: Attempt To Free Heap Memory |
5908 | ** |
5909 | ** ^The sqlite3_release_memory() interface attempts to free N bytes |
5910 | ** of heap memory by deallocating non-essential memory allocations |
5911 | ** held by the database library. Memory used to cache database |
5912 | ** pages to improve performance is an example of non-essential memory. |
5913 | ** ^sqlite3_release_memory() returns the number of bytes actually freed, |
5914 | ** which might be more or less than the amount requested. |
5915 | ** ^The sqlite3_release_memory() routine is a no-op returning zero |
5916 | ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT]. |
5917 | ** |
5918 | ** See also: [sqlite3_db_release_memory()] |
5919 | */ |
5920 | SQLITE_API int sqlite3_release_memory(int); |
5921 | |
5922 | /* |
5923 | ** CAPI3REF: Free Memory Used By A Database Connection |
5924 | ** METHOD: sqlite3 |
5925 | ** |
5926 | ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap |
5927 | ** memory as possible from database connection D. Unlike the |
5928 | ** [sqlite3_release_memory()] interface, this interface is in effect even |
5929 | ** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is |
5930 | ** omitted. |
5931 | ** |
5932 | ** See also: [sqlite3_release_memory()] |
5933 | */ |
5934 | SQLITE_API int sqlite3_db_release_memory(sqlite3*); |
5935 | |
5936 | /* |
5937 | ** CAPI3REF: Impose A Limit On Heap Size |
5938 | ** |
5939 | ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the |
5940 | ** soft limit on the amount of heap memory that may be allocated by SQLite. |
5941 | ** ^SQLite strives to keep heap memory utilization below the soft heap |
5942 | ** limit by reducing the number of pages held in the page cache |
5943 | ** as heap memory usages approaches the limit. |
5944 | ** ^The soft heap limit is "soft" because even though SQLite strives to stay |
5945 | ** below the limit, it will exceed the limit rather than generate |
5946 | ** an [SQLITE_NOMEM] error. In other words, the soft heap limit |
5947 | ** is advisory only. |
5948 | ** |
5949 | ** ^The return value from sqlite3_soft_heap_limit64() is the size of |
5950 | ** the soft heap limit prior to the call, or negative in the case of an |
5951 | ** error. ^If the argument N is negative |
5952 | ** then no change is made to the soft heap limit. Hence, the current |
5953 | ** size of the soft heap limit can be determined by invoking |
5954 | ** sqlite3_soft_heap_limit64() with a negative argument. |
5955 | ** |
5956 | ** ^If the argument N is zero then the soft heap limit is disabled. |
5957 | ** |
5958 | ** ^(The soft heap limit is not enforced in the current implementation |
5959 | ** if one or more of following conditions are true: |
5960 | ** |
5961 | ** <ul> |
5962 | ** <li> The soft heap limit is set to zero. |
5963 | ** <li> Memory accounting is disabled using a combination of the |
5964 | ** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and |
5965 | ** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option. |
5966 | ** <li> An alternative page cache implementation is specified using |
5967 | ** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...). |
5968 | ** <li> The page cache allocates from its own memory pool supplied |
5969 | ** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than |
5970 | ** from the heap. |
5971 | ** </ul>)^ |
5972 | ** |
5973 | ** Beginning with SQLite [version 3.7.3] ([dateof:3.7.3]), |
5974 | ** the soft heap limit is enforced |
5975 | ** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT] |
5976 | ** compile-time option is invoked. With [SQLITE_ENABLE_MEMORY_MANAGEMENT], |
5977 | ** the soft heap limit is enforced on every memory allocation. Without |
5978 | ** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced |
5979 | ** when memory is allocated by the page cache. Testing suggests that because |
5980 | ** the page cache is the predominate memory user in SQLite, most |
5981 | ** applications will achieve adequate soft heap limit enforcement without |
5982 | ** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT]. |
5983 | ** |
5984 | ** The circumstances under which SQLite will enforce the soft heap limit may |
5985 | ** changes in future releases of SQLite. |
5986 | */ |
5987 | SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N); |
5988 | |
5989 | /* |
5990 | ** CAPI3REF: Deprecated Soft Heap Limit Interface |
5991 | ** DEPRECATED |
5992 | ** |
5993 | ** This is a deprecated version of the [sqlite3_soft_heap_limit64()] |
5994 | ** interface. This routine is provided for historical compatibility |
5995 | ** only. All new applications should use the |
5996 | ** [sqlite3_soft_heap_limit64()] interface rather than this one. |
5997 | */ |
5998 | SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N); |
5999 | |
6000 | |
6001 | /* |
6002 | ** CAPI3REF: Extract Metadata About A Column Of A Table |
6003 | ** METHOD: sqlite3 |
6004 | ** |
6005 | ** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns |
6006 | ** information about column C of table T in database D |
6007 | ** on [database connection] X.)^ ^The sqlite3_table_column_metadata() |
6008 | ** interface returns SQLITE_OK and fills in the non-NULL pointers in |
6009 | ** the final five arguments with appropriate values if the specified |
6010 | ** column exists. ^The sqlite3_table_column_metadata() interface returns |
6011 | ** SQLITE_ERROR and if the specified column does not exist. |
6012 | ** ^If the column-name parameter to sqlite3_table_column_metadata() is a |
6013 | ** NULL pointer, then this routine simply checks for the existence of the |
6014 | ** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it |
6015 | ** does not. If the table name parameter T in a call to |
6016 | ** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is |
6017 | ** undefined behavior. |
6018 | ** |
6019 | ** ^The column is identified by the second, third and fourth parameters to |
6020 | ** this function. ^(The second parameter is either the name of the database |
6021 | ** (i.e. "main", "temp", or an attached database) containing the specified |
6022 | ** table or NULL.)^ ^If it is NULL, then all attached databases are searched |
6023 | ** for the table using the same algorithm used by the database engine to |
6024 | ** resolve unqualified table references. |
6025 | ** |
6026 | ** ^The third and fourth parameters to this function are the table and column |
6027 | ** name of the desired column, respectively. |
6028 | ** |
6029 | ** ^Metadata is returned by writing to the memory locations passed as the 5th |
6030 | ** and subsequent parameters to this function. ^Any of these arguments may be |
6031 | ** NULL, in which case the corresponding element of metadata is omitted. |
6032 | ** |
6033 | ** ^(<blockquote> |
6034 | ** <table border="1"> |
6035 | ** <tr><th> Parameter <th> Output<br>Type <th> Description |
6036 | ** |
6037 | ** <tr><td> 5th <td> const char* <td> Data type |
6038 | ** <tr><td> 6th <td> const char* <td> Name of default collation sequence |
6039 | ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint |
6040 | ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY |
6041 | ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT] |
6042 | ** </table> |
6043 | ** </blockquote>)^ |
6044 | ** |
6045 | ** ^The memory pointed to by the character pointers returned for the |
6046 | ** declaration type and collation sequence is valid until the next |
6047 | ** call to any SQLite API function. |
6048 | ** |
6049 | ** ^If the specified table is actually a view, an [error code] is returned. |
6050 | ** |
6051 | ** ^If the specified column is "rowid", "oid" or "_rowid_" and the table |
6052 | ** is not a [WITHOUT ROWID] table and an |
6053 | ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output |
6054 | ** parameters are set for the explicitly declared column. ^(If there is no |
6055 | ** [INTEGER PRIMARY KEY] column, then the outputs |
6056 | ** for the [rowid] are set as follows: |
6057 | ** |
6058 | ** <pre> |
6059 | ** data type: "INTEGER" |
6060 | ** collation sequence: "BINARY" |
6061 | ** not null: 0 |
6062 | ** primary key: 1 |
6063 | ** auto increment: 0 |
6064 | ** </pre>)^ |
6065 | ** |
6066 | ** ^This function causes all database schemas to be read from disk and |
6067 | ** parsed, if that has not already been done, and returns an error if |
6068 | ** any errors are encountered while loading the schema. |
6069 | */ |
6070 | SQLITE_API int sqlite3_table_column_metadata( |
6071 | sqlite3 *db, /* Connection handle */ |
6072 | const char *zDbName, /* Database name or NULL */ |
6073 | const char *zTableName, /* Table name */ |
6074 | const char *zColumnName, /* Column name */ |
6075 | char const **pzDataType, /* OUTPUT: Declared data type */ |
6076 | char const **pzCollSeq, /* OUTPUT: Collation sequence name */ |
6077 | int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ |
6078 | int *pPrimaryKey, /* OUTPUT: True if column part of PK */ |
6079 | int *pAutoinc /* OUTPUT: True if column is auto-increment */ |
6080 | ); |
6081 | |
6082 | /* |
6083 | ** CAPI3REF: Load An Extension |
6084 | ** METHOD: sqlite3 |
6085 | ** |
6086 | ** ^This interface loads an SQLite extension library from the named file. |
6087 | ** |
6088 | ** ^The sqlite3_load_extension() interface attempts to load an |
6089 | ** [SQLite extension] library contained in the file zFile. If |
6090 | ** the file cannot be loaded directly, attempts are made to load |
6091 | ** with various operating-system specific extensions added. |
6092 | ** So for example, if "samplelib" cannot be loaded, then names like |
6093 | ** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might |
6094 | ** be tried also. |
6095 | ** |
6096 | ** ^The entry point is zProc. |
6097 | ** ^(zProc may be 0, in which case SQLite will try to come up with an |
6098 | ** entry point name on its own. It first tries "sqlite3_extension_init". |
6099 | ** If that does not work, it constructs a name "sqlite3_X_init" where the |
6100 | ** X is consists of the lower-case equivalent of all ASCII alphabetic |
6101 | ** characters in the filename from the last "/" to the first following |
6102 | ** "." and omitting any initial "lib".)^ |
6103 | ** ^The sqlite3_load_extension() interface returns |
6104 | ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. |
6105 | ** ^If an error occurs and pzErrMsg is not 0, then the |
6106 | ** [sqlite3_load_extension()] interface shall attempt to |
6107 | ** fill *pzErrMsg with error message text stored in memory |
6108 | ** obtained from [sqlite3_malloc()]. The calling function |
6109 | ** should free this memory by calling [sqlite3_free()]. |
6110 | ** |
6111 | ** ^Extension loading must be enabled using |
6112 | ** [sqlite3_enable_load_extension()] or |
6113 | ** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL) |
6114 | ** prior to calling this API, |
6115 | ** otherwise an error will be returned. |
6116 | ** |
6117 | ** <b>Security warning:</b> It is recommended that the |
6118 | ** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this |
6119 | ** interface. The use of the [sqlite3_enable_load_extension()] interface |
6120 | ** should be avoided. This will keep the SQL function [load_extension()] |
6121 | ** disabled and prevent SQL injections from giving attackers |
6122 | ** access to extension loading capabilities. |
6123 | ** |
6124 | ** See also the [load_extension() SQL function]. |
6125 | */ |
6126 | SQLITE_API int sqlite3_load_extension( |
6127 | sqlite3 *db, /* Load the extension into this database connection */ |
6128 | const char *zFile, /* Name of the shared library containing extension */ |
6129 | const char *zProc, /* Entry point. Derived from zFile if 0 */ |
6130 | char **pzErrMsg /* Put error message here if not 0 */ |
6131 | ); |
6132 | |
6133 | /* |
6134 | ** CAPI3REF: Enable Or Disable Extension Loading |
6135 | ** METHOD: sqlite3 |
6136 | ** |
6137 | ** ^So as not to open security holes in older applications that are |
6138 | ** unprepared to deal with [extension loading], and as a means of disabling |
6139 | ** [extension loading] while evaluating user-entered SQL, the following API |
6140 | ** is provided to turn the [sqlite3_load_extension()] mechanism on and off. |
6141 | ** |
6142 | ** ^Extension loading is off by default. |
6143 | ** ^Call the sqlite3_enable_load_extension() routine with onoff==1 |
6144 | ** to turn extension loading on and call it with onoff==0 to turn |
6145 | ** it back off again. |
6146 | ** |
6147 | ** ^This interface enables or disables both the C-API |
6148 | ** [sqlite3_load_extension()] and the SQL function [load_extension()]. |
6149 | ** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..) |
6150 | ** to enable or disable only the C-API.)^ |
6151 | ** |
6152 | ** <b>Security warning:</b> It is recommended that extension loading |
6153 | ** be disabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method |
6154 | ** rather than this interface, so the [load_extension()] SQL function |
6155 | ** remains disabled. This will prevent SQL injections from giving attackers |
6156 | ** access to extension loading capabilities. |
6157 | */ |
6158 | SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff); |
6159 | |
6160 | /* |
6161 | ** CAPI3REF: Automatically Load Statically Linked Extensions |
6162 | ** |
6163 | ** ^This interface causes the xEntryPoint() function to be invoked for |
6164 | ** each new [database connection] that is created. The idea here is that |
6165 | ** xEntryPoint() is the entry point for a statically linked [SQLite extension] |
6166 | ** that is to be automatically loaded into all new database connections. |
6167 | ** |
6168 | ** ^(Even though the function prototype shows that xEntryPoint() takes |
6169 | ** no arguments and returns void, SQLite invokes xEntryPoint() with three |
6170 | ** arguments and expects an integer result as if the signature of the |
6171 | ** entry point where as follows: |
6172 | ** |
6173 | ** <blockquote><pre> |
6174 | ** int xEntryPoint( |
6175 | ** sqlite3 *db, |
6176 | ** const char **pzErrMsg, |
6177 | ** const struct sqlite3_api_routines *pThunk |
6178 | ** ); |
6179 | ** </pre></blockquote>)^ |
6180 | ** |
6181 | ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg |
6182 | ** point to an appropriate error message (obtained from [sqlite3_mprintf()]) |
6183 | ** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg |
6184 | ** is NULL before calling the xEntryPoint(). ^SQLite will invoke |
6185 | ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any |
6186 | ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()], |
6187 | ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail. |
6188 | ** |
6189 | ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already |
6190 | ** on the list of automatic extensions is a harmless no-op. ^No entry point |
6191 | ** will be called more than once for each database connection that is opened. |
6192 | ** |
6193 | ** See also: [sqlite3_reset_auto_extension()] |
6194 | ** and [sqlite3_cancel_auto_extension()] |
6195 | */ |
6196 | SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void)); |
6197 | |
6198 | /* |
6199 | ** CAPI3REF: Cancel Automatic Extension Loading |
6200 | ** |
6201 | ** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the |
6202 | ** initialization routine X that was registered using a prior call to |
6203 | ** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)] |
6204 | ** routine returns 1 if initialization routine X was successfully |
6205 | ** unregistered and it returns 0 if X was not on the list of initialization |
6206 | ** routines. |
6207 | */ |
6208 | SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void)); |
6209 | |
6210 | /* |
6211 | ** CAPI3REF: Reset Automatic Extension Loading |
6212 | ** |
6213 | ** ^This interface disables all automatic extensions previously |
6214 | ** registered using [sqlite3_auto_extension()]. |
6215 | */ |
6216 | SQLITE_API void sqlite3_reset_auto_extension(void); |
6217 | |
6218 | /* |
6219 | ** The interface to the virtual-table mechanism is currently considered |
6220 | ** to be experimental. The interface might change in incompatible ways. |
6221 | ** If this is a problem for you, do not use the interface at this time. |
6222 | ** |
6223 | ** When the virtual-table mechanism stabilizes, we will declare the |
6224 | ** interface fixed, support it indefinitely, and remove this comment. |
6225 | */ |
6226 | |
6227 | /* |
6228 | ** Structures used by the virtual table interface |
6229 | */ |
6230 | typedef struct sqlite3_vtab sqlite3_vtab; |
6231 | typedef struct sqlite3_index_info sqlite3_index_info; |
6232 | typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; |
6233 | typedef struct sqlite3_module sqlite3_module; |
6234 | |
6235 | /* |
6236 | ** CAPI3REF: Virtual Table Object |
6237 | ** KEYWORDS: sqlite3_module {virtual table module} |
6238 | ** |
6239 | ** This structure, sometimes called a "virtual table module", |
6240 | ** defines the implementation of a [virtual tables]. |
6241 | ** This structure consists mostly of methods for the module. |
6242 | ** |
6243 | ** ^A virtual table module is created by filling in a persistent |
6244 | ** instance of this structure and passing a pointer to that instance |
6245 | ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. |
6246 | ** ^The registration remains valid until it is replaced by a different |
6247 | ** module or until the [database connection] closes. The content |
6248 | ** of this structure must not change while it is registered with |
6249 | ** any database connection. |
6250 | */ |
6251 | struct sqlite3_module { |
6252 | int iVersion; |
6253 | int (*xCreate)(sqlite3*, void *pAux, |
6254 | int argc, const char *const*argv, |
6255 | sqlite3_vtab **ppVTab, char**); |
6256 | int (*xConnect)(sqlite3*, void *pAux, |
6257 | int argc, const char *const*argv, |
6258 | sqlite3_vtab **ppVTab, char**); |
6259 | int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); |
6260 | int (*xDisconnect)(sqlite3_vtab *pVTab); |
6261 | int (*xDestroy)(sqlite3_vtab *pVTab); |
6262 | int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); |
6263 | int (*xClose)(sqlite3_vtab_cursor*); |
6264 | int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, |
6265 | int argc, sqlite3_value **argv); |
6266 | int (*xNext)(sqlite3_vtab_cursor*); |
6267 | int (*xEof)(sqlite3_vtab_cursor*); |
6268 | int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); |
6269 | int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); |
6270 | int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); |
6271 | int (*xBegin)(sqlite3_vtab *pVTab); |
6272 | int (*xSync)(sqlite3_vtab *pVTab); |
6273 | int (*xCommit)(sqlite3_vtab *pVTab); |
6274 | int (*xRollback)(sqlite3_vtab *pVTab); |
6275 | int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, |
6276 | void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), |
6277 | void **ppArg); |
6278 | int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); |
6279 | /* The methods above are in version 1 of the sqlite_module object. Those |
6280 | ** below are for version 2 and greater. */ |
6281 | int (*xSavepoint)(sqlite3_vtab *pVTab, int); |
6282 | int (*xRelease)(sqlite3_vtab *pVTab, int); |
6283 | int (*xRollbackTo)(sqlite3_vtab *pVTab, int); |
6284 | }; |
6285 | |
6286 | /* |
6287 | ** CAPI3REF: Virtual Table Indexing Information |
6288 | ** KEYWORDS: sqlite3_index_info |
6289 | ** |
6290 | ** The sqlite3_index_info structure and its substructures is used as part |
6291 | ** of the [virtual table] interface to |
6292 | ** pass information into and receive the reply from the [xBestIndex] |
6293 | ** method of a [virtual table module]. The fields under **Inputs** are the |
6294 | ** inputs to xBestIndex and are read-only. xBestIndex inserts its |
6295 | ** results into the **Outputs** fields. |
6296 | ** |
6297 | ** ^(The aConstraint[] array records WHERE clause constraints of the form: |
6298 | ** |
6299 | ** <blockquote>column OP expr</blockquote> |
6300 | ** |
6301 | ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is |
6302 | ** stored in aConstraint[].op using one of the |
6303 | ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^ |
6304 | ** ^(The index of the column is stored in |
6305 | ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the |
6306 | ** expr on the right-hand side can be evaluated (and thus the constraint |
6307 | ** is usable) and false if it cannot.)^ |
6308 | ** |
6309 | ** ^The optimizer automatically inverts terms of the form "expr OP column" |
6310 | ** and makes other simplifications to the WHERE clause in an attempt to |
6311 | ** get as many WHERE clause terms into the form shown above as possible. |
6312 | ** ^The aConstraint[] array only reports WHERE clause terms that are |
6313 | ** relevant to the particular virtual table being queried. |
6314 | ** |
6315 | ** ^Information about the ORDER BY clause is stored in aOrderBy[]. |
6316 | ** ^Each term of aOrderBy records a column of the ORDER BY clause. |
6317 | ** |
6318 | ** The colUsed field indicates which columns of the virtual table may be |
6319 | ** required by the current scan. Virtual table columns are numbered from |
6320 | ** zero in the order in which they appear within the CREATE TABLE statement |
6321 | ** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62), |
6322 | ** the corresponding bit is set within the colUsed mask if the column may be |
6323 | ** required by SQLite. If the table has at least 64 columns and any column |
6324 | ** to the right of the first 63 is required, then bit 63 of colUsed is also |
6325 | ** set. In other words, column iCol may be required if the expression |
6326 | ** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to |
6327 | ** non-zero. |
6328 | ** |
6329 | ** The [xBestIndex] method must fill aConstraintUsage[] with information |
6330 | ** about what parameters to pass to xFilter. ^If argvIndex>0 then |
6331 | ** the right-hand side of the corresponding aConstraint[] is evaluated |
6332 | ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit |
6333 | ** is true, then the constraint is assumed to be fully handled by the |
6334 | ** virtual table and is not checked again by SQLite.)^ |
6335 | ** |
6336 | ** ^The idxNum and idxPtr values are recorded and passed into the |
6337 | ** [xFilter] method. |
6338 | ** ^[sqlite3_free()] is used to free idxPtr if and only if |
6339 | ** needToFreeIdxPtr is true. |
6340 | ** |
6341 | ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in |
6342 | ** the correct order to satisfy the ORDER BY clause so that no separate |
6343 | ** sorting step is required. |
6344 | ** |
6345 | ** ^The estimatedCost value is an estimate of the cost of a particular |
6346 | ** strategy. A cost of N indicates that the cost of the strategy is similar |
6347 | ** to a linear scan of an SQLite table with N rows. A cost of log(N) |
6348 | ** indicates that the expense of the operation is similar to that of a |
6349 | ** binary search on a unique indexed field of an SQLite table with N rows. |
6350 | ** |
6351 | ** ^The estimatedRows value is an estimate of the number of rows that |
6352 | ** will be returned by the strategy. |
6353 | ** |
6354 | ** The xBestIndex method may optionally populate the idxFlags field with a |
6355 | ** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag - |
6356 | ** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite |
6357 | ** assumes that the strategy may visit at most one row. |
6358 | ** |
6359 | ** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then |
6360 | ** SQLite also assumes that if a call to the xUpdate() method is made as |
6361 | ** part of the same statement to delete or update a virtual table row and the |
6362 | ** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback |
6363 | ** any database changes. In other words, if the xUpdate() returns |
6364 | ** SQLITE_CONSTRAINT, the database contents must be exactly as they were |
6365 | ** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not |
6366 | ** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by |
6367 | ** the xUpdate method are automatically rolled back by SQLite. |
6368 | ** |
6369 | ** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info |
6370 | ** structure for SQLite [version 3.8.2] ([dateof:3.8.2]). |
6371 | ** If a virtual table extension is |
6372 | ** used with an SQLite version earlier than 3.8.2, the results of attempting |
6373 | ** to read or write the estimatedRows field are undefined (but are likely |
6374 | ** to included crashing the application). The estimatedRows field should |
6375 | ** therefore only be used if [sqlite3_libversion_number()] returns a |
6376 | ** value greater than or equal to 3008002. Similarly, the idxFlags field |
6377 | ** was added for [version 3.9.0] ([dateof:3.9.0]). |
6378 | ** It may therefore only be used if |
6379 | ** sqlite3_libversion_number() returns a value greater than or equal to |
6380 | ** 3009000. |
6381 | */ |
6382 | struct sqlite3_index_info { |
6383 | /* Inputs */ |
6384 | int nConstraint; /* Number of entries in aConstraint */ |
6385 | struct sqlite3_index_constraint { |
6386 | int iColumn; /* Column constrained. -1 for ROWID */ |
6387 | unsigned char op; /* Constraint operator */ |
6388 | unsigned char usable; /* True if this constraint is usable */ |
6389 | int iTermOffset; /* Used internally - xBestIndex should ignore */ |
6390 | } *aConstraint; /* Table of WHERE clause constraints */ |
6391 | int nOrderBy; /* Number of terms in the ORDER BY clause */ |
6392 | struct sqlite3_index_orderby { |
6393 | int iColumn; /* Column number */ |
6394 | unsigned char desc; /* True for DESC. False for ASC. */ |
6395 | } *aOrderBy; /* The ORDER BY clause */ |
6396 | /* Outputs */ |
6397 | struct sqlite3_index_constraint_usage { |
6398 | int argvIndex; /* if >0, constraint is part of argv to xFilter */ |
6399 | unsigned char omit; /* Do not code a test for this constraint */ |
6400 | } *aConstraintUsage; |
6401 | int idxNum; /* Number used to identify the index */ |
6402 | char *idxStr; /* String, possibly obtained from sqlite3_malloc */ |
6403 | int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ |
6404 | int orderByConsumed; /* True if output is already ordered */ |
6405 | double estimatedCost; /* Estimated cost of using this index */ |
6406 | /* Fields below are only available in SQLite 3.8.2 and later */ |
6407 | sqlite3_int64 estimatedRows; /* Estimated number of rows returned */ |
6408 | /* Fields below are only available in SQLite 3.9.0 and later */ |
6409 | int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */ |
6410 | /* Fields below are only available in SQLite 3.10.0 and later */ |
6411 | sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */ |
6412 | }; |
6413 | |
6414 | /* |
6415 | ** CAPI3REF: Virtual Table Scan Flags |
6416 | ** |
6417 | ** Virtual table implementations are allowed to set the |
6418 | ** [sqlite3_index_info].idxFlags field to some combination of |
6419 | ** these bits. |
6420 | */ |
6421 | #define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */ |
6422 | |
6423 | /* |
6424 | ** CAPI3REF: Virtual Table Constraint Operator Codes |
6425 | ** |
6426 | ** These macros defined the allowed values for the |
6427 | ** [sqlite3_index_info].aConstraint[].op field. Each value represents |
6428 | ** an operator that is part of a constraint term in the wHERE clause of |
6429 | ** a query that uses a [virtual table]. |
6430 | */ |
6431 | #define SQLITE_INDEX_CONSTRAINT_EQ 2 |
6432 | #define SQLITE_INDEX_CONSTRAINT_GT 4 |
6433 | #define SQLITE_INDEX_CONSTRAINT_LE 8 |
6434 | #define SQLITE_INDEX_CONSTRAINT_LT 16 |
6435 | #define SQLITE_INDEX_CONSTRAINT_GE 32 |
6436 | #define SQLITE_INDEX_CONSTRAINT_MATCH 64 |
6437 | #define SQLITE_INDEX_CONSTRAINT_LIKE 65 |
6438 | #define SQLITE_INDEX_CONSTRAINT_GLOB 66 |
6439 | #define SQLITE_INDEX_CONSTRAINT_REGEXP 67 |
6440 | #define SQLITE_INDEX_CONSTRAINT_NE 68 |
6441 | #define SQLITE_INDEX_CONSTRAINT_ISNOT 69 |
6442 | #define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70 |
6443 | #define SQLITE_INDEX_CONSTRAINT_ISNULL 71 |
6444 | #define SQLITE_INDEX_CONSTRAINT_IS 72 |
6445 | #define SQLITE_INDEX_CONSTRAINT_FUNCTION 150 |
6446 | |
6447 | /* |
6448 | ** CAPI3REF: Register A Virtual Table Implementation |
6449 | ** METHOD: sqlite3 |
6450 | ** |
6451 | ** ^These routines are used to register a new [virtual table module] name. |
6452 | ** ^Module names must be registered before |
6453 | ** creating a new [virtual table] using the module and before using a |
6454 | ** preexisting [virtual table] for the module. |
6455 | ** |
6456 | ** ^The module name is registered on the [database connection] specified |
6457 | ** by the first parameter. ^The name of the module is given by the |
6458 | ** second parameter. ^The third parameter is a pointer to |
6459 | ** the implementation of the [virtual table module]. ^The fourth |
6460 | ** parameter is an arbitrary client data pointer that is passed through |
6461 | ** into the [xCreate] and [xConnect] methods of the virtual table module |
6462 | ** when a new virtual table is be being created or reinitialized. |
6463 | ** |
6464 | ** ^The sqlite3_create_module_v2() interface has a fifth parameter which |
6465 | ** is a pointer to a destructor for the pClientData. ^SQLite will |
6466 | ** invoke the destructor function (if it is not NULL) when SQLite |
6467 | ** no longer needs the pClientData pointer. ^The destructor will also |
6468 | ** be invoked if the call to sqlite3_create_module_v2() fails. |
6469 | ** ^The sqlite3_create_module() |
6470 | ** interface is equivalent to sqlite3_create_module_v2() with a NULL |
6471 | ** destructor. |
6472 | */ |
6473 | SQLITE_API int sqlite3_create_module( |
6474 | sqlite3 *db, /* SQLite connection to register module with */ |
6475 | const char *zName, /* Name of the module */ |
6476 | const sqlite3_module *p, /* Methods for the module */ |
6477 | void *pClientData /* Client data for xCreate/xConnect */ |
6478 | ); |
6479 | SQLITE_API int sqlite3_create_module_v2( |
6480 | sqlite3 *db, /* SQLite connection to register module with */ |
6481 | const char *zName, /* Name of the module */ |
6482 | const sqlite3_module *p, /* Methods for the module */ |
6483 | void *pClientData, /* Client data for xCreate/xConnect */ |
6484 | void(*xDestroy)(void*) /* Module destructor function */ |
6485 | ); |
6486 | |
6487 | /* |
6488 | ** CAPI3REF: Virtual Table Instance Object |
6489 | ** KEYWORDS: sqlite3_vtab |
6490 | ** |
6491 | ** Every [virtual table module] implementation uses a subclass |
6492 | ** of this object to describe a particular instance |
6493 | ** of the [virtual table]. Each subclass will |
6494 | ** be tailored to the specific needs of the module implementation. |
6495 | ** The purpose of this superclass is to define certain fields that are |
6496 | ** common to all module implementations. |
6497 | ** |
6498 | ** ^Virtual tables methods can set an error message by assigning a |
6499 | ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should |
6500 | ** take care that any prior string is freed by a call to [sqlite3_free()] |
6501 | ** prior to assigning a new string to zErrMsg. ^After the error message |
6502 | ** is delivered up to the client application, the string will be automatically |
6503 | ** freed by sqlite3_free() and the zErrMsg field will be zeroed. |
6504 | */ |
6505 | struct sqlite3_vtab { |
6506 | const sqlite3_module *pModule; /* The module for this virtual table */ |
6507 | int nRef; /* Number of open cursors */ |
6508 | char *zErrMsg; /* Error message from sqlite3_mprintf() */ |
6509 | /* Virtual table implementations will typically add additional fields */ |
6510 | }; |
6511 | |
6512 | /* |
6513 | ** CAPI3REF: Virtual Table Cursor Object |
6514 | ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} |
6515 | ** |
6516 | ** Every [virtual table module] implementation uses a subclass of the |
6517 | ** following structure to describe cursors that point into the |
6518 | ** [virtual table] and are used |
6519 | ** to loop through the virtual table. Cursors are created using the |
6520 | ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed |
6521 | ** by the [sqlite3_module.xClose | xClose] method. Cursors are used |
6522 | ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods |
6523 | ** of the module. Each module implementation will define |
6524 | ** the content of a cursor structure to suit its own needs. |
6525 | ** |
6526 | ** This superclass exists in order to define fields of the cursor that |
6527 | ** are common to all implementations. |
6528 | */ |
6529 | struct sqlite3_vtab_cursor { |
6530 | sqlite3_vtab *pVtab; /* Virtual table of this cursor */ |
6531 | /* Virtual table implementations will typically add additional fields */ |
6532 | }; |
6533 | |
6534 | /* |
6535 | ** CAPI3REF: Declare The Schema Of A Virtual Table |
6536 | ** |
6537 | ** ^The [xCreate] and [xConnect] methods of a |
6538 | ** [virtual table module] call this interface |
6539 | ** to declare the format (the names and datatypes of the columns) of |
6540 | ** the virtual tables they implement. |
6541 | */ |
6542 | SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL); |
6543 | |
6544 | /* |
6545 | ** CAPI3REF: Overload A Function For A Virtual Table |
6546 | ** METHOD: sqlite3 |
6547 | ** |
6548 | ** ^(Virtual tables can provide alternative implementations of functions |
6549 | ** using the [xFindFunction] method of the [virtual table module]. |
6550 | ** But global versions of those functions |
6551 | ** must exist in order to be overloaded.)^ |
6552 | ** |
6553 | ** ^(This API makes sure a global version of a function with a particular |
6554 | ** name and number of parameters exists. If no such function exists |
6555 | ** before this API is called, a new function is created.)^ ^The implementation |
6556 | ** of the new function always causes an exception to be thrown. So |
6557 | ** the new function is not good for anything by itself. Its only |
6558 | ** purpose is to be a placeholder function that can be overloaded |
6559 | ** by a [virtual table]. |
6560 | */ |
6561 | SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); |
6562 | |
6563 | /* |
6564 | ** The interface to the virtual-table mechanism defined above (back up |
6565 | ** to a comment remarkably similar to this one) is currently considered |
6566 | ** to be experimental. The interface might change in incompatible ways. |
6567 | ** If this is a problem for you, do not use the interface at this time. |
6568 | ** |
6569 | ** When the virtual-table mechanism stabilizes, we will declare the |
6570 | ** interface fixed, support it indefinitely, and remove this comment. |
6571 | */ |
6572 | |
6573 | /* |
6574 | ** CAPI3REF: A Handle To An Open BLOB |
6575 | ** KEYWORDS: {BLOB handle} {BLOB handles} |
6576 | ** |
6577 | ** An instance of this object represents an open BLOB on which |
6578 | ** [sqlite3_blob_open | incremental BLOB I/O] can be performed. |
6579 | ** ^Objects of this type are created by [sqlite3_blob_open()] |
6580 | ** and destroyed by [sqlite3_blob_close()]. |
6581 | ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces |
6582 | ** can be used to read or write small subsections of the BLOB. |
6583 | ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. |
6584 | */ |
6585 | typedef struct sqlite3_blob sqlite3_blob; |
6586 | |
6587 | /* |
6588 | ** CAPI3REF: Open A BLOB For Incremental I/O |
6589 | ** METHOD: sqlite3 |
6590 | ** CONSTRUCTOR: sqlite3_blob |
6591 | ** |
6592 | ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located |
6593 | ** in row iRow, column zColumn, table zTable in database zDb; |
6594 | ** in other words, the same BLOB that would be selected by: |
6595 | ** |
6596 | ** <pre> |
6597 | ** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow; |
6598 | ** </pre>)^ |
6599 | ** |
6600 | ** ^(Parameter zDb is not the filename that contains the database, but |
6601 | ** rather the symbolic name of the database. For attached databases, this is |
6602 | ** the name that appears after the AS keyword in the [ATTACH] statement. |
6603 | ** For the main database file, the database name is "main". For TEMP |
6604 | ** tables, the database name is "temp".)^ |
6605 | ** |
6606 | ** ^If the flags parameter is non-zero, then the BLOB is opened for read |
6607 | ** and write access. ^If the flags parameter is zero, the BLOB is opened for |
6608 | ** read-only access. |
6609 | ** |
6610 | ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored |
6611 | ** in *ppBlob. Otherwise an [error code] is returned and, unless the error |
6612 | ** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided |
6613 | ** the API is not misused, it is always safe to call [sqlite3_blob_close()] |
6614 | ** on *ppBlob after this function it returns. |
6615 | ** |
6616 | ** This function fails with SQLITE_ERROR if any of the following are true: |
6617 | ** <ul> |
6618 | ** <li> ^(Database zDb does not exist)^, |
6619 | ** <li> ^(Table zTable does not exist within database zDb)^, |
6620 | ** <li> ^(Table zTable is a WITHOUT ROWID table)^, |
6621 | ** <li> ^(Column zColumn does not exist)^, |
6622 | ** <li> ^(Row iRow is not present in the table)^, |
6623 | ** <li> ^(The specified column of row iRow contains a value that is not |
6624 | ** a TEXT or BLOB value)^, |
6625 | ** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE |
6626 | ** constraint and the blob is being opened for read/write access)^, |
6627 | ** <li> ^([foreign key constraints | Foreign key constraints] are enabled, |
6628 | ** column zColumn is part of a [child key] definition and the blob is |
6629 | ** being opened for read/write access)^. |
6630 | ** </ul> |
6631 | ** |
6632 | ** ^Unless it returns SQLITE_MISUSE, this function sets the |
6633 | ** [database connection] error code and message accessible via |
6634 | ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. |
6635 | ** |
6636 | ** A BLOB referenced by sqlite3_blob_open() may be read using the |
6637 | ** [sqlite3_blob_read()] interface and modified by using |
6638 | ** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a |
6639 | ** different row of the same table using the [sqlite3_blob_reopen()] |
6640 | ** interface. However, the column, table, or database of a [BLOB handle] |
6641 | ** cannot be changed after the [BLOB handle] is opened. |
6642 | ** |
6643 | ** ^(If the row that a BLOB handle points to is modified by an |
6644 | ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects |
6645 | ** then the BLOB handle is marked as "expired". |
6646 | ** This is true if any column of the row is changed, even a column |
6647 | ** other than the one the BLOB handle is open on.)^ |
6648 | ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for |
6649 | ** an expired BLOB handle fail with a return code of [SQLITE_ABORT]. |
6650 | ** ^(Changes written into a BLOB prior to the BLOB expiring are not |
6651 | ** rolled back by the expiration of the BLOB. Such changes will eventually |
6652 | ** commit if the transaction continues to completion.)^ |
6653 | ** |
6654 | ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of |
6655 | ** the opened blob. ^The size of a blob may not be changed by this |
6656 | ** interface. Use the [UPDATE] SQL command to change the size of a |
6657 | ** blob. |
6658 | ** |
6659 | ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces |
6660 | ** and the built-in [zeroblob] SQL function may be used to create a |
6661 | ** zero-filled blob to read or write using the incremental-blob interface. |
6662 | ** |
6663 | ** To avoid a resource leak, every open [BLOB handle] should eventually |
6664 | ** be released by a call to [sqlite3_blob_close()]. |
6665 | ** |
6666 | ** See also: [sqlite3_blob_close()], |
6667 | ** [sqlite3_blob_reopen()], [sqlite3_blob_read()], |
6668 | ** [sqlite3_blob_bytes()], [sqlite3_blob_write()]. |
6669 | */ |
6670 | SQLITE_API int sqlite3_blob_open( |
6671 | sqlite3*, |
6672 | const char *zDb, |
6673 | const char *zTable, |
6674 | const char *zColumn, |
6675 | sqlite3_int64 iRow, |
6676 | int flags, |
6677 | sqlite3_blob **ppBlob |
6678 | ); |
6679 | |
6680 | /* |
6681 | ** CAPI3REF: Move a BLOB Handle to a New Row |
6682 | ** METHOD: sqlite3_blob |
6683 | ** |
6684 | ** ^This function is used to move an existing [BLOB handle] so that it points |
6685 | ** to a different row of the same database table. ^The new row is identified |
6686 | ** by the rowid value passed as the second argument. Only the row can be |
6687 | ** changed. ^The database, table and column on which the blob handle is open |
6688 | ** remain the same. Moving an existing [BLOB handle] to a new row is |
6689 | ** faster than closing the existing handle and opening a new one. |
6690 | ** |
6691 | ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] - |
6692 | ** it must exist and there must be either a blob or text value stored in |
6693 | ** the nominated column.)^ ^If the new row is not present in the table, or if |
6694 | ** it does not contain a blob or text value, or if another error occurs, an |
6695 | ** SQLite error code is returned and the blob handle is considered aborted. |
6696 | ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or |
6697 | ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return |
6698 | ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle |
6699 | ** always returns zero. |
6700 | ** |
6701 | ** ^This function sets the database handle error code and message. |
6702 | */ |
6703 | SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64); |
6704 | |
6705 | /* |
6706 | ** CAPI3REF: Close A BLOB Handle |
6707 | ** DESTRUCTOR: sqlite3_blob |
6708 | ** |
6709 | ** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed |
6710 | ** unconditionally. Even if this routine returns an error code, the |
6711 | ** handle is still closed.)^ |
6712 | ** |
6713 | ** ^If the blob handle being closed was opened for read-write access, and if |
6714 | ** the database is in auto-commit mode and there are no other open read-write |
6715 | ** blob handles or active write statements, the current transaction is |
6716 | ** committed. ^If an error occurs while committing the transaction, an error |
6717 | ** code is returned and the transaction rolled back. |
6718 | ** |
6719 | ** Calling this function with an argument that is not a NULL pointer or an |
6720 | ** open blob handle results in undefined behaviour. ^Calling this routine |
6721 | ** with a null pointer (such as would be returned by a failed call to |
6722 | ** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function |
6723 | ** is passed a valid open blob handle, the values returned by the |
6724 | ** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning. |
6725 | */ |
6726 | SQLITE_API int sqlite3_blob_close(sqlite3_blob *); |
6727 | |
6728 | /* |
6729 | ** CAPI3REF: Return The Size Of An Open BLOB |
6730 | ** METHOD: sqlite3_blob |
6731 | ** |
6732 | ** ^Returns the size in bytes of the BLOB accessible via the |
6733 | ** successfully opened [BLOB handle] in its only argument. ^The |
6734 | ** incremental blob I/O routines can only read or overwriting existing |
6735 | ** blob content; they cannot change the size of a blob. |
6736 | ** |
6737 | ** This routine only works on a [BLOB handle] which has been created |
6738 | ** by a prior successful call to [sqlite3_blob_open()] and which has not |
6739 | ** been closed by [sqlite3_blob_close()]. Passing any other pointer in |
6740 | ** to this routine results in undefined and probably undesirable behavior. |
6741 | */ |
6742 | SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *); |
6743 | |
6744 | /* |
6745 | ** CAPI3REF: Read Data From A BLOB Incrementally |
6746 | ** METHOD: sqlite3_blob |
6747 | ** |
6748 | ** ^(This function is used to read data from an open [BLOB handle] into a |
6749 | ** caller-supplied buffer. N bytes of data are copied into buffer Z |
6750 | ** from the open BLOB, starting at offset iOffset.)^ |
6751 | ** |
6752 | ** ^If offset iOffset is less than N bytes from the end of the BLOB, |
6753 | ** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is |
6754 | ** less than zero, [SQLITE_ERROR] is returned and no data is read. |
6755 | ** ^The size of the blob (and hence the maximum value of N+iOffset) |
6756 | ** can be determined using the [sqlite3_blob_bytes()] interface. |
6757 | ** |
6758 | ** ^An attempt to read from an expired [BLOB handle] fails with an |
6759 | ** error code of [SQLITE_ABORT]. |
6760 | ** |
6761 | ** ^(On success, sqlite3_blob_read() returns SQLITE_OK. |
6762 | ** Otherwise, an [error code] or an [extended error code] is returned.)^ |
6763 | ** |
6764 | ** This routine only works on a [BLOB handle] which has been created |
6765 | ** by a prior successful call to [sqlite3_blob_open()] and which has not |
6766 | ** been closed by [sqlite3_blob_close()]. Passing any other pointer in |
6767 | ** to this routine results in undefined and probably undesirable behavior. |
6768 | ** |
6769 | ** See also: [sqlite3_blob_write()]. |
6770 | */ |
6771 | SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); |
6772 | |
6773 | /* |
6774 | ** CAPI3REF: Write Data Into A BLOB Incrementally |
6775 | ** METHOD: sqlite3_blob |
6776 | ** |
6777 | ** ^(This function is used to write data into an open [BLOB handle] from a |
6778 | ** caller-supplied buffer. N bytes of data are copied from the buffer Z |
6779 | ** into the open BLOB, starting at offset iOffset.)^ |
6780 | ** |
6781 | ** ^(On success, sqlite3_blob_write() returns SQLITE_OK. |
6782 | ** Otherwise, an [error code] or an [extended error code] is returned.)^ |
6783 | ** ^Unless SQLITE_MISUSE is returned, this function sets the |
6784 | ** [database connection] error code and message accessible via |
6785 | ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. |
6786 | ** |
6787 | ** ^If the [BLOB handle] passed as the first argument was not opened for |
6788 | ** writing (the flags parameter to [sqlite3_blob_open()] was zero), |
6789 | ** this function returns [SQLITE_READONLY]. |
6790 | ** |
6791 | ** This function may only modify the contents of the BLOB; it is |
6792 | ** not possible to increase the size of a BLOB using this API. |
6793 | ** ^If offset iOffset is less than N bytes from the end of the BLOB, |
6794 | ** [SQLITE_ERROR] is returned and no data is written. The size of the |
6795 | ** BLOB (and hence the maximum value of N+iOffset) can be determined |
6796 | ** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less |
6797 | ** than zero [SQLITE_ERROR] is returned and no data is written. |
6798 | ** |
6799 | ** ^An attempt to write to an expired [BLOB handle] fails with an |
6800 | ** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred |
6801 | ** before the [BLOB handle] expired are not rolled back by the |
6802 | ** expiration of the handle, though of course those changes might |
6803 | ** have been overwritten by the statement that expired the BLOB handle |
6804 | ** or by other independent statements. |
6805 | ** |
6806 | ** This routine only works on a [BLOB handle] which has been created |
6807 | ** by a prior successful call to [sqlite3_blob_open()] and which has not |
6808 | ** been closed by [sqlite3_blob_close()]. Passing any other pointer in |
6809 | ** to this routine results in undefined and probably undesirable behavior. |
6810 | ** |
6811 | ** See also: [sqlite3_blob_read()]. |
6812 | */ |
6813 | SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); |
6814 | |
6815 | /* |
6816 | ** CAPI3REF: Virtual File System Objects |
6817 | ** |
6818 | ** A virtual filesystem (VFS) is an [sqlite3_vfs] object |
6819 | ** that SQLite uses to interact |
6820 | ** with the underlying operating system. Most SQLite builds come with a |
6821 | ** single default VFS that is appropriate for the host computer. |
6822 | ** New VFSes can be registered and existing VFSes can be unregistered. |
6823 | ** The following interfaces are provided. |
6824 | ** |
6825 | ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. |
6826 | ** ^Names are case sensitive. |
6827 | ** ^Names are zero-terminated UTF-8 strings. |
6828 | ** ^If there is no match, a NULL pointer is returned. |
6829 | ** ^If zVfsName is NULL then the default VFS is returned. |
6830 | ** |
6831 | ** ^New VFSes are registered with sqlite3_vfs_register(). |
6832 | ** ^Each new VFS becomes the default VFS if the makeDflt flag is set. |
6833 | ** ^The same VFS can be registered multiple times without injury. |
6834 | ** ^To make an existing VFS into the default VFS, register it again |
6835 | ** with the makeDflt flag set. If two different VFSes with the |
6836 | ** same name are registered, the behavior is undefined. If a |
6837 | ** VFS is registered with a name that is NULL or an empty string, |
6838 | ** then the behavior is undefined. |
6839 | ** |
6840 | ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface. |
6841 | ** ^(If the default VFS is unregistered, another VFS is chosen as |
6842 | ** the default. The choice for the new VFS is arbitrary.)^ |
6843 | */ |
6844 | SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); |
6845 | SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); |
6846 | SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*); |
6847 | |
6848 | /* |
6849 | ** CAPI3REF: Mutexes |
6850 | ** |
6851 | ** The SQLite core uses these routines for thread |
6852 | ** synchronization. Though they are intended for internal |
6853 | ** use by SQLite, code that links against SQLite is |
6854 | ** permitted to use any of these routines. |
6855 | ** |
6856 | ** The SQLite source code contains multiple implementations |
6857 | ** of these mutex routines. An appropriate implementation |
6858 | ** is selected automatically at compile-time. The following |
6859 | ** implementations are available in the SQLite core: |
6860 | ** |
6861 | ** <ul> |
6862 | ** <li> SQLITE_MUTEX_PTHREADS |
6863 | ** <li> SQLITE_MUTEX_W32 |
6864 | ** <li> SQLITE_MUTEX_NOOP |
6865 | ** </ul> |
6866 | ** |
6867 | ** The SQLITE_MUTEX_NOOP implementation is a set of routines |
6868 | ** that does no real locking and is appropriate for use in |
6869 | ** a single-threaded application. The SQLITE_MUTEX_PTHREADS and |
6870 | ** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix |
6871 | ** and Windows. |
6872 | ** |
6873 | ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor |
6874 | ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex |
6875 | ** implementation is included with the library. In this case the |
6876 | ** application must supply a custom mutex implementation using the |
6877 | ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function |
6878 | ** before calling sqlite3_initialize() or any other public sqlite3_ |
6879 | ** function that calls sqlite3_initialize(). |
6880 | ** |
6881 | ** ^The sqlite3_mutex_alloc() routine allocates a new |
6882 | ** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc() |
6883 | ** routine returns NULL if it is unable to allocate the requested |
6884 | ** mutex. The argument to sqlite3_mutex_alloc() must one of these |
6885 | ** integer constants: |
6886 | ** |
6887 | ** <ul> |
6888 | ** <li> SQLITE_MUTEX_FAST |
6889 | ** <li> SQLITE_MUTEX_RECURSIVE |
6890 | ** <li> SQLITE_MUTEX_STATIC_MASTER |
6891 | ** <li> SQLITE_MUTEX_STATIC_MEM |
6892 | ** <li> SQLITE_MUTEX_STATIC_OPEN |
6893 | ** <li> SQLITE_MUTEX_STATIC_PRNG |
6894 | ** <li> SQLITE_MUTEX_STATIC_LRU |
6895 | ** <li> SQLITE_MUTEX_STATIC_PMEM |
6896 | ** <li> SQLITE_MUTEX_STATIC_APP1 |
6897 | ** <li> SQLITE_MUTEX_STATIC_APP2 |
6898 | ** <li> SQLITE_MUTEX_STATIC_APP3 |
6899 | ** <li> SQLITE_MUTEX_STATIC_VFS1 |
6900 | ** <li> SQLITE_MUTEX_STATIC_VFS2 |
6901 | ** <li> SQLITE_MUTEX_STATIC_VFS3 |
6902 | ** </ul> |
6903 | ** |
6904 | ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) |
6905 | ** cause sqlite3_mutex_alloc() to create |
6906 | ** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE |
6907 | ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. |
6908 | ** The mutex implementation does not need to make a distinction |
6909 | ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does |
6910 | ** not want to. SQLite will only request a recursive mutex in |
6911 | ** cases where it really needs one. If a faster non-recursive mutex |
6912 | ** implementation is available on the host platform, the mutex subsystem |
6913 | ** might return such a mutex in response to SQLITE_MUTEX_FAST. |
6914 | ** |
6915 | ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other |
6916 | ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return |
6917 | ** a pointer to a static preexisting mutex. ^Nine static mutexes are |
6918 | ** used by the current version of SQLite. Future versions of SQLite |
6919 | ** may add additional static mutexes. Static mutexes are for internal |
6920 | ** use by SQLite only. Applications that use SQLite mutexes should |
6921 | ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or |
6922 | ** SQLITE_MUTEX_RECURSIVE. |
6923 | ** |
6924 | ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST |
6925 | ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() |
6926 | ** returns a different mutex on every call. ^For the static |
6927 | ** mutex types, the same mutex is returned on every call that has |
6928 | ** the same type number. |
6929 | ** |
6930 | ** ^The sqlite3_mutex_free() routine deallocates a previously |
6931 | ** allocated dynamic mutex. Attempting to deallocate a static |
6932 | ** mutex results in undefined behavior. |
6933 | ** |
6934 | ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt |
6935 | ** to enter a mutex. ^If another thread is already within the mutex, |
6936 | ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return |
6937 | ** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK] |
6938 | ** upon successful entry. ^(Mutexes created using |
6939 | ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. |
6940 | ** In such cases, the |
6941 | ** mutex must be exited an equal number of times before another thread |
6942 | ** can enter.)^ If the same thread tries to enter any mutex other |
6943 | ** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined. |
6944 | ** |
6945 | ** ^(Some systems (for example, Windows 95) do not support the operation |
6946 | ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() |
6947 | ** will always return SQLITE_BUSY. The SQLite core only ever uses |
6948 | ** sqlite3_mutex_try() as an optimization so this is acceptable |
6949 | ** behavior.)^ |
6950 | ** |
6951 | ** ^The sqlite3_mutex_leave() routine exits a mutex that was |
6952 | ** previously entered by the same thread. The behavior |
6953 | ** is undefined if the mutex is not currently entered by the |
6954 | ** calling thread or is not currently allocated. |
6955 | ** |
6956 | ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or |
6957 | ** sqlite3_mutex_leave() is a NULL pointer, then all three routines |
6958 | ** behave as no-ops. |
6959 | ** |
6960 | ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. |
6961 | */ |
6962 | SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int); |
6963 | SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*); |
6964 | SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*); |
6965 | SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*); |
6966 | SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*); |
6967 | |
6968 | /* |
6969 | ** CAPI3REF: Mutex Methods Object |
6970 | ** |
6971 | ** An instance of this structure defines the low-level routines |
6972 | ** used to allocate and use mutexes. |
6973 | ** |
6974 | ** Usually, the default mutex implementations provided by SQLite are |
6975 | ** sufficient, however the application has the option of substituting a custom |
6976 | ** implementation for specialized deployments or systems for which SQLite |
6977 | ** does not provide a suitable implementation. In this case, the application |
6978 | ** creates and populates an instance of this structure to pass |
6979 | ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. |
6980 | ** Additionally, an instance of this structure can be used as an |
6981 | ** output variable when querying the system for the current mutex |
6982 | ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. |
6983 | ** |
6984 | ** ^The xMutexInit method defined by this structure is invoked as |
6985 | ** part of system initialization by the sqlite3_initialize() function. |
6986 | ** ^The xMutexInit routine is called by SQLite exactly once for each |
6987 | ** effective call to [sqlite3_initialize()]. |
6988 | ** |
6989 | ** ^The xMutexEnd method defined by this structure is invoked as |
6990 | ** part of system shutdown by the sqlite3_shutdown() function. The |
6991 | ** implementation of this method is expected to release all outstanding |
6992 | ** resources obtained by the mutex methods implementation, especially |
6993 | ** those obtained by the xMutexInit method. ^The xMutexEnd() |
6994 | ** interface is invoked exactly once for each call to [sqlite3_shutdown()]. |
6995 | ** |
6996 | ** ^(The remaining seven methods defined by this structure (xMutexAlloc, |
6997 | ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and |
6998 | ** xMutexNotheld) implement the following interfaces (respectively): |
6999 | ** |
7000 | ** <ul> |
7001 | ** <li> [sqlite3_mutex_alloc()] </li> |
7002 | ** <li> [sqlite3_mutex_free()] </li> |
7003 | ** <li> [sqlite3_mutex_enter()] </li> |
7004 | ** <li> [sqlite3_mutex_try()] </li> |
7005 | ** <li> [sqlite3_mutex_leave()] </li> |
7006 | ** <li> [sqlite3_mutex_held()] </li> |
7007 | ** <li> [sqlite3_mutex_notheld()] </li> |
7008 | ** </ul>)^ |
7009 | ** |
7010 | ** The only difference is that the public sqlite3_XXX functions enumerated |
7011 | ** above silently ignore any invocations that pass a NULL pointer instead |
7012 | ** of a valid mutex handle. The implementations of the methods defined |
7013 | ** by this structure are not required to handle this case, the results |
7014 | ** of passing a NULL pointer instead of a valid mutex handle are undefined |
7015 | ** (i.e. it is acceptable to provide an implementation that segfaults if |
7016 | ** it is passed a NULL pointer). |
7017 | ** |
7018 | ** The xMutexInit() method must be threadsafe. It must be harmless to |
7019 | ** invoke xMutexInit() multiple times within the same process and without |
7020 | ** intervening calls to xMutexEnd(). Second and subsequent calls to |
7021 | ** xMutexInit() must be no-ops. |
7022 | ** |
7023 | ** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] |
7024 | ** and its associates). Similarly, xMutexAlloc() must not use SQLite memory |
7025 | ** allocation for a static mutex. ^However xMutexAlloc() may use SQLite |
7026 | ** memory allocation for a fast or recursive mutex. |
7027 | ** |
7028 | ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is |
7029 | ** called, but only if the prior call to xMutexInit returned SQLITE_OK. |
7030 | ** If xMutexInit fails in any way, it is expected to clean up after itself |
7031 | ** prior to returning. |
7032 | */ |
7033 | typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; |
7034 | struct sqlite3_mutex_methods { |
7035 | int (*xMutexInit)(void); |
7036 | int (*xMutexEnd)(void); |
7037 | sqlite3_mutex *(*xMutexAlloc)(int); |
7038 | void (*xMutexFree)(sqlite3_mutex *); |
7039 | void (*xMutexEnter)(sqlite3_mutex *); |
7040 | int (*xMutexTry)(sqlite3_mutex *); |
7041 | void (*xMutexLeave)(sqlite3_mutex *); |
7042 | int (*xMutexHeld)(sqlite3_mutex *); |
7043 | int (*xMutexNotheld)(sqlite3_mutex *); |
7044 | }; |
7045 | |
7046 | /* |
7047 | ** CAPI3REF: Mutex Verification Routines |
7048 | ** |
7049 | ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines |
7050 | ** are intended for use inside assert() statements. The SQLite core |
7051 | ** never uses these routines except inside an assert() and applications |
7052 | ** are advised to follow the lead of the core. The SQLite core only |
7053 | ** provides implementations for these routines when it is compiled |
7054 | ** with the SQLITE_DEBUG flag. External mutex implementations |
7055 | ** are only required to provide these routines if SQLITE_DEBUG is |
7056 | ** defined and if NDEBUG is not defined. |
7057 | ** |
7058 | ** These routines should return true if the mutex in their argument |
7059 | ** is held or not held, respectively, by the calling thread. |
7060 | ** |
7061 | ** The implementation is not required to provide versions of these |
7062 | ** routines that actually work. If the implementation does not provide working |
7063 | ** versions of these routines, it should at least provide stubs that always |
7064 | ** return true so that one does not get spurious assertion failures. |
7065 | ** |
7066 | ** If the argument to sqlite3_mutex_held() is a NULL pointer then |
7067 | ** the routine should return 1. This seems counter-intuitive since |
7068 | ** clearly the mutex cannot be held if it does not exist. But |
7069 | ** the reason the mutex does not exist is because the build is not |
7070 | ** using mutexes. And we do not want the assert() containing the |
7071 | ** call to sqlite3_mutex_held() to fail, so a non-zero return is |
7072 | ** the appropriate thing to do. The sqlite3_mutex_notheld() |
7073 | ** interface should also return 1 when given a NULL pointer. |
7074 | */ |
7075 | #ifndef NDEBUG |
7076 | SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*); |
7077 | SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*); |
7078 | #endif |
7079 | |
7080 | /* |
7081 | ** CAPI3REF: Mutex Types |
7082 | ** |
7083 | ** The [sqlite3_mutex_alloc()] interface takes a single argument |
7084 | ** which is one of these integer constants. |
7085 | ** |
7086 | ** The set of static mutexes may change from one SQLite release to the |
7087 | ** next. Applications that override the built-in mutex logic must be |
7088 | ** prepared to accommodate additional static mutexes. |
7089 | */ |
7090 | #define SQLITE_MUTEX_FAST 0 |
7091 | #define SQLITE_MUTEX_RECURSIVE 1 |
7092 | #define SQLITE_MUTEX_STATIC_MASTER 2 |
7093 | #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ |
7094 | #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ |
7095 | #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ |
7096 | #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */ |
7097 | #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ |
7098 | #define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */ |
7099 | #define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */ |
7100 | #define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */ |
7101 | #define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */ |
7102 | #define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */ |
7103 | #define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */ |
7104 | #define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */ |
7105 | #define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */ |
7106 | |
7107 | /* |
7108 | ** CAPI3REF: Retrieve the mutex for a database connection |
7109 | ** METHOD: sqlite3 |
7110 | ** |
7111 | ** ^This interface returns a pointer the [sqlite3_mutex] object that |
7112 | ** serializes access to the [database connection] given in the argument |
7113 | ** when the [threading mode] is Serialized. |
7114 | ** ^If the [threading mode] is Single-thread or Multi-thread then this |
7115 | ** routine returns a NULL pointer. |
7116 | */ |
7117 | SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*); |
7118 | |
7119 | /* |
7120 | ** CAPI3REF: Low-Level Control Of Database Files |
7121 | ** METHOD: sqlite3 |
7122 | ** KEYWORDS: {file control} |
7123 | ** |
7124 | ** ^The [sqlite3_file_control()] interface makes a direct call to the |
7125 | ** xFileControl method for the [sqlite3_io_methods] object associated |
7126 | ** with a particular database identified by the second argument. ^The |
7127 | ** name of the database is "main" for the main database or "temp" for the |
7128 | ** TEMP database, or the name that appears after the AS keyword for |
7129 | ** databases that are added using the [ATTACH] SQL command. |
7130 | ** ^A NULL pointer can be used in place of "main" to refer to the |
7131 | ** main database file. |
7132 | ** ^The third and fourth parameters to this routine |
7133 | ** are passed directly through to the second and third parameters of |
7134 | ** the xFileControl method. ^The return value of the xFileControl |
7135 | ** method becomes the return value of this routine. |
7136 | ** |
7137 | ** A few opcodes for [sqlite3_file_control()] are handled directly |
7138 | ** by the SQLite core and never invoke the |
7139 | ** sqlite3_io_methods.xFileControl method. |
7140 | ** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes |
7141 | ** a pointer to the underlying [sqlite3_file] object to be written into |
7142 | ** the space pointed to by the 4th parameter. The |
7143 | ** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns |
7144 | ** the [sqlite3_file] object associated with the journal file instead of |
7145 | ** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns |
7146 | ** a pointer to the underlying [sqlite3_vfs] object for the file. |
7147 | ** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter |
7148 | ** from the pager. |
7149 | ** |
7150 | ** ^If the second parameter (zDbName) does not match the name of any |
7151 | ** open database file, then SQLITE_ERROR is returned. ^This error |
7152 | ** code is not remembered and will not be recalled by [sqlite3_errcode()] |
7153 | ** or [sqlite3_errmsg()]. The underlying xFileControl method might |
7154 | ** also return SQLITE_ERROR. There is no way to distinguish between |
7155 | ** an incorrect zDbName and an SQLITE_ERROR return from the underlying |
7156 | ** xFileControl method. |
7157 | ** |
7158 | ** See also: [file control opcodes] |
7159 | */ |
7160 | SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); |
7161 | |
7162 | /* |
7163 | ** CAPI3REF: Testing Interface |
7164 | ** |
7165 | ** ^The sqlite3_test_control() interface is used to read out internal |
7166 | ** state of SQLite and to inject faults into SQLite for testing |
7167 | ** purposes. ^The first parameter is an operation code that determines |
7168 | ** the number, meaning, and operation of all subsequent parameters. |
7169 | ** |
7170 | ** This interface is not for use by applications. It exists solely |
7171 | ** for verifying the correct operation of the SQLite library. Depending |
7172 | ** on how the SQLite library is compiled, this interface might not exist. |
7173 | ** |
7174 | ** The details of the operation codes, their meanings, the parameters |
7175 | ** they take, and what they do are all subject to change without notice. |
7176 | ** Unlike most of the SQLite API, this function is not guaranteed to |
7177 | ** operate consistently from one release to the next. |
7178 | */ |
7179 | SQLITE_API int sqlite3_test_control(int op, ...); |
7180 | |
7181 | /* |
7182 | ** CAPI3REF: Testing Interface Operation Codes |
7183 | ** |
7184 | ** These constants are the valid operation code parameters used |
7185 | ** as the first argument to [sqlite3_test_control()]. |
7186 | ** |
7187 | ** These parameters and their meanings are subject to change |
7188 | ** without notice. These values are for testing purposes only. |
7189 | ** Applications should not use any of these parameters or the |
7190 | ** [sqlite3_test_control()] interface. |
7191 | */ |
7192 | #define SQLITE_TESTCTRL_FIRST 5 |
7193 | #define SQLITE_TESTCTRL_PRNG_SAVE 5 |
7194 | #define SQLITE_TESTCTRL_PRNG_RESTORE 6 |
7195 | #define SQLITE_TESTCTRL_PRNG_RESET 7 |
7196 | #define SQLITE_TESTCTRL_BITVEC_TEST 8 |
7197 | #define SQLITE_TESTCTRL_FAULT_INSTALL 9 |
7198 | #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 |
7199 | #define SQLITE_TESTCTRL_PENDING_BYTE 11 |
7200 | #define SQLITE_TESTCTRL_ASSERT 12 |
7201 | #define SQLITE_TESTCTRL_ALWAYS 13 |
7202 | #define SQLITE_TESTCTRL_RESERVE 14 |
7203 | #define SQLITE_TESTCTRL_OPTIMIZATIONS 15 |
7204 | #define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */ |
7205 | #define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */ |
7206 | #define SQLITE_TESTCTRL_LOCALTIME_FAULT 18 |
7207 | #define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */ |
7208 | #define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19 |
7209 | #define SQLITE_TESTCTRL_NEVER_CORRUPT 20 |
7210 | #define SQLITE_TESTCTRL_VDBE_COVERAGE 21 |
7211 | #define SQLITE_TESTCTRL_BYTEORDER 22 |
7212 | #define SQLITE_TESTCTRL_ISINIT 23 |
7213 | #define SQLITE_TESTCTRL_SORTER_MMAP 24 |
7214 | #define SQLITE_TESTCTRL_IMPOSTER 25 |
7215 | #define SQLITE_TESTCTRL_PARSER_COVERAGE 26 |
7216 | #define SQLITE_TESTCTRL_LAST 26 /* Largest TESTCTRL */ |
7217 | |
7218 | /* |
7219 | ** CAPI3REF: SQL Keyword Checking |
7220 | ** |
7221 | ** These routines provide access to the set of SQL language keywords |
7222 | ** recognized by SQLite. Applications can uses these routines to determine |
7223 | ** whether or not a specific identifier needs to be escaped (for example, |
7224 | ** by enclosing in double-quotes) so as not to confuse the parser. |
7225 | ** |
7226 | ** The sqlite3_keyword_count() interface returns the number of distinct |
7227 | ** keywords understood by SQLite. |
7228 | ** |
7229 | ** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and |
7230 | ** makes *Z point to that keyword expressed as UTF8 and writes the number |
7231 | ** of bytes in the keyword into *L. The string that *Z points to is not |
7232 | ** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns |
7233 | ** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z |
7234 | ** or L are NULL or invalid pointers then calls to |
7235 | ** sqlite3_keyword_name(N,Z,L) result in undefined behavior. |
7236 | ** |
7237 | ** The sqlite3_keyword_check(Z,L) interface checks to see whether or not |
7238 | ** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero |
7239 | ** if it is and zero if not. |
7240 | ** |
7241 | ** The parser used by SQLite is forgiving. It is often possible to use |
7242 | ** a keyword as an identifier as long as such use does not result in a |
7243 | ** parsing ambiguity. For example, the statement |
7244 | ** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and |
7245 | ** creates a new table named "BEGIN" with three columns named |
7246 | ** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid |
7247 | ** using keywords as identifiers. Common techniques used to avoid keyword |
7248 | ** name collisions include: |
7249 | ** <ul> |
7250 | ** <li> Put all identifier names inside double-quotes. This is the official |
7251 | ** SQL way to escape identifier names. |
7252 | ** <li> Put identifier names inside [...]. This is not standard SQL, |
7253 | ** but it is what SQL Server does and so lots of programmers use this |
7254 | ** technique. |
7255 | ** <li> Begin every identifier with the letter "Z" as no SQL keywords start |
7256 | ** with "Z". |
7257 | ** <li> Include a digit somewhere in every identifier name. |
7258 | ** </ul> |
7259 | ** |
7260 | ** Note that the number of keywords understood by SQLite can depend on |
7261 | ** compile-time options. For example, "VACUUM" is not a keyword if |
7262 | ** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also, |
7263 | ** new keywords may be added to future releases of SQLite. |
7264 | */ |
7265 | SQLITE_API int sqlite3_keyword_count(void); |
7266 | SQLITE_API int sqlite3_keyword_name(int,const char**,int*); |
7267 | SQLITE_API int sqlite3_keyword_check(const char*,int); |
7268 | |
7269 | /* |
7270 | ** CAPI3REF: Dynamic String Object |
7271 | ** KEYWORDS: {dynamic string} |
7272 | ** |
7273 | ** An instance of the sqlite3_str object contains a dynamically-sized |
7274 | ** string under construction. |
7275 | ** |
7276 | ** The lifecycle of an sqlite3_str object is as follows: |
7277 | ** <ol> |
7278 | ** <li> ^The sqlite3_str object is created using [sqlite3_str_new()]. |
7279 | ** <li> ^Text is appended to the sqlite3_str object using various |
7280 | ** methods, such as [sqlite3_str_appendf()]. |
7281 | ** <li> ^The sqlite3_str object is destroyed and the string it created |
7282 | ** is returned using the [sqlite3_str_finish()] interface. |
7283 | ** </ol> |
7284 | */ |
7285 | typedef struct sqlite3_str sqlite3_str; |
7286 | |
7287 | /* |
7288 | ** CAPI3REF: Create A New Dynamic String Object |
7289 | ** CONSTRUCTOR: sqlite3_str |
7290 | ** |
7291 | ** ^The [sqlite3_str_new(D)] interface allocates and initializes |
7292 | ** a new [sqlite3_str] object. To avoid memory leaks, the object returned by |
7293 | ** [sqlite3_str_new()] must be freed by a subsequent call to |
7294 | ** [sqlite3_str_finish(X)]. |
7295 | ** |
7296 | ** ^The [sqlite3_str_new(D)] interface always returns a pointer to a |
7297 | ** valid [sqlite3_str] object, though in the event of an out-of-memory |
7298 | ** error the returned object might be a special singleton that will |
7299 | ** silently reject new text, always return SQLITE_NOMEM from |
7300 | ** [sqlite3_str_errcode()], always return 0 for |
7301 | ** [sqlite3_str_length()], and always return NULL from |
7302 | ** [sqlite3_str_finish(X)]. It is always safe to use the value |
7303 | ** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter |
7304 | ** to any of the other [sqlite3_str] methods. |
7305 | ** |
7306 | ** The D parameter to [sqlite3_str_new(D)] may be NULL. If the |
7307 | ** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum |
7308 | ** length of the string contained in the [sqlite3_str] object will be |
7309 | ** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead |
7310 | ** of [SQLITE_MAX_LENGTH]. |
7311 | */ |
7312 | SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*); |
7313 | |
7314 | /* |
7315 | ** CAPI3REF: Finalize A Dynamic String |
7316 | ** DESTRUCTOR: sqlite3_str |
7317 | ** |
7318 | ** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X |
7319 | ** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()] |
7320 | ** that contains the constructed string. The calling application should |
7321 | ** pass the returned value to [sqlite3_free()] to avoid a memory leak. |
7322 | ** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any |
7323 | ** errors were encountered during construction of the string. ^The |
7324 | ** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the |
7325 | ** string in [sqlite3_str] object X is zero bytes long. |
7326 | */ |
7327 | SQLITE_API char *sqlite3_str_finish(sqlite3_str*); |
7328 | |
7329 | /* |
7330 | ** CAPI3REF: Add Content To A Dynamic String |
7331 | ** METHOD: sqlite3_str |
7332 | ** |
7333 | ** These interfaces add content to an sqlite3_str object previously obtained |
7334 | ** from [sqlite3_str_new()]. |
7335 | ** |
7336 | ** ^The [sqlite3_str_appendf(X,F,...)] and |
7337 | ** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf] |
7338 | ** functionality of SQLite to append formatted text onto the end of |
7339 | ** [sqlite3_str] object X. |
7340 | ** |
7341 | ** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S |
7342 | ** onto the end of the [sqlite3_str] object X. N must be non-negative. |
7343 | ** S must contain at least N non-zero bytes of content. To append a |
7344 | ** zero-terminated string in its entirety, use the [sqlite3_str_appendall()] |
7345 | ** method instead. |
7346 | ** |
7347 | ** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of |
7348 | ** zero-terminated string S onto the end of [sqlite3_str] object X. |
7349 | ** |
7350 | ** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the |
7351 | ** single-byte character C onto the end of [sqlite3_str] object X. |
7352 | ** ^This method can be used, for example, to add whitespace indentation. |
7353 | ** |
7354 | ** ^The [sqlite3_str_reset(X)] method resets the string under construction |
7355 | ** inside [sqlite3_str] object X back to zero bytes in length. |
7356 | ** |
7357 | ** These methods do not return a result code. ^If an error occurs, that fact |
7358 | ** is recorded in the [sqlite3_str] object and can be recovered by a |
7359 | ** subsequent call to [sqlite3_str_errcode(X)]. |
7360 | */ |
7361 | SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...); |
7362 | SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list); |
7363 | SQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N); |
7364 | SQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn); |
7365 | SQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C); |
7366 | SQLITE_API void sqlite3_str_reset(sqlite3_str*); |
7367 | |
7368 | /* |
7369 | ** CAPI3REF: Status Of A Dynamic String |
7370 | ** METHOD: sqlite3_str |
7371 | ** |
7372 | ** These interfaces return the current status of an [sqlite3_str] object. |
7373 | ** |
7374 | ** ^If any prior errors have occurred while constructing the dynamic string |
7375 | ** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return |
7376 | ** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns |
7377 | ** [SQLITE_NOMEM] following any out-of-memory error, or |
7378 | ** [SQLITE_TOOBIG] if the size of the dynamic string exceeds |
7379 | ** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors. |
7380 | ** |
7381 | ** ^The [sqlite3_str_length(X)] method returns the current length, in bytes, |
7382 | ** of the dynamic string under construction in [sqlite3_str] object X. |
7383 | ** ^The length returned by [sqlite3_str_length(X)] does not include the |
7384 | ** zero-termination byte. |
7385 | ** |
7386 | ** ^The [sqlite3_str_value(X)] method returns a pointer to the current |
7387 | ** content of the dynamic string under construction in X. The value |
7388 | ** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X |
7389 | ** and might be freed or altered by any subsequent method on the same |
7390 | ** [sqlite3_str] object. Applications must not used the pointer returned |
7391 | ** [sqlite3_str_value(X)] after any subsequent method call on the same |
7392 | ** object. ^Applications may change the content of the string returned |
7393 | ** by [sqlite3_str_value(X)] as long as they do not write into any bytes |
7394 | ** outside the range of 0 to [sqlite3_str_length(X)] and do not read or |
7395 | ** write any byte after any subsequent sqlite3_str method call. |
7396 | */ |
7397 | SQLITE_API int sqlite3_str_errcode(sqlite3_str*); |
7398 | SQLITE_API int sqlite3_str_length(sqlite3_str*); |
7399 | SQLITE_API char *sqlite3_str_value(sqlite3_str*); |
7400 | |
7401 | /* |
7402 | ** CAPI3REF: SQLite Runtime Status |
7403 | ** |
7404 | ** ^These interfaces are used to retrieve runtime status information |
7405 | ** about the performance of SQLite, and optionally to reset various |
7406 | ** highwater marks. ^The first argument is an integer code for |
7407 | ** the specific parameter to measure. ^(Recognized integer codes |
7408 | ** are of the form [status parameters | SQLITE_STATUS_...].)^ |
7409 | ** ^The current value of the parameter is returned into *pCurrent. |
7410 | ** ^The highest recorded value is returned in *pHighwater. ^If the |
7411 | ** resetFlag is true, then the highest record value is reset after |
7412 | ** *pHighwater is written. ^(Some parameters do not record the highest |
7413 | ** value. For those parameters |
7414 | ** nothing is written into *pHighwater and the resetFlag is ignored.)^ |
7415 | ** ^(Other parameters record only the highwater mark and not the current |
7416 | ** value. For these latter parameters nothing is written into *pCurrent.)^ |
7417 | ** |
7418 | ** ^The sqlite3_status() and sqlite3_status64() routines return |
7419 | ** SQLITE_OK on success and a non-zero [error code] on failure. |
7420 | ** |
7421 | ** If either the current value or the highwater mark is too large to |
7422 | ** be represented by a 32-bit integer, then the values returned by |
7423 | ** sqlite3_status() are undefined. |
7424 | ** |
7425 | ** See also: [sqlite3_db_status()] |
7426 | */ |
7427 | SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); |
7428 | SQLITE_API int sqlite3_status64( |
7429 | int op, |
7430 | sqlite3_int64 *pCurrent, |
7431 | sqlite3_int64 *pHighwater, |
7432 | int resetFlag |
7433 | ); |
7434 | |
7435 | |
7436 | /* |
7437 | ** CAPI3REF: Status Parameters |
7438 | ** KEYWORDS: {status parameters} |
7439 | ** |
7440 | ** These integer constants designate various run-time status parameters |
7441 | ** that can be returned by [sqlite3_status()]. |
7442 | ** |
7443 | ** <dl> |
7444 | ** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt> |
7445 | ** <dd>This parameter is the current amount of memory checked out |
7446 | ** using [sqlite3_malloc()], either directly or indirectly. The |
7447 | ** figure includes calls made to [sqlite3_malloc()] by the application |
7448 | ** and internal memory usage by the SQLite library. Auxiliary page-cache |
7449 | ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in |
7450 | ** this parameter. The amount returned is the sum of the allocation |
7451 | ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^ |
7452 | ** |
7453 | ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt> |
7454 | ** <dd>This parameter records the largest memory allocation request |
7455 | ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their |
7456 | ** internal equivalents). Only the value returned in the |
7457 | ** *pHighwater parameter to [sqlite3_status()] is of interest. |
7458 | ** The value written into the *pCurrent parameter is undefined.</dd>)^ |
7459 | ** |
7460 | ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt> |
7461 | ** <dd>This parameter records the number of separate memory allocations |
7462 | ** currently checked out.</dd>)^ |
7463 | ** |
7464 | ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt> |
7465 | ** <dd>This parameter returns the number of pages used out of the |
7466 | ** [pagecache memory allocator] that was configured using |
7467 | ** [SQLITE_CONFIG_PAGECACHE]. The |
7468 | ** value returned is in pages, not in bytes.</dd>)^ |
7469 | ** |
7470 | ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] |
7471 | ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt> |
7472 | ** <dd>This parameter returns the number of bytes of page cache |
7473 | ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE] |
7474 | ** buffer and where forced to overflow to [sqlite3_malloc()]. The |
7475 | ** returned value includes allocations that overflowed because they |
7476 | ** where too large (they were larger than the "sz" parameter to |
7477 | ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because |
7478 | ** no space was left in the page cache.</dd>)^ |
7479 | ** |
7480 | ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt> |
7481 | ** <dd>This parameter records the largest memory allocation request |
7482 | ** handed to [pagecache memory allocator]. Only the value returned in the |
7483 | ** *pHighwater parameter to [sqlite3_status()] is of interest. |
7484 | ** The value written into the *pCurrent parameter is undefined.</dd>)^ |
7485 | ** |
7486 | ** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt> |
7487 | ** <dd>No longer used.</dd> |
7488 | ** |
7489 | ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt> |
7490 | ** <dd>No longer used.</dd> |
7491 | ** |
7492 | ** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt> |
7493 | ** <dd>No longer used.</dd> |
7494 | ** |
7495 | ** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt> |
7496 | ** <dd>The *pHighwater parameter records the deepest parser stack. |
7497 | ** The *pCurrent value is undefined. The *pHighwater value is only |
7498 | ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^ |
7499 | ** </dl> |
7500 | ** |
7501 | ** New status parameters may be added from time to time. |
7502 | */ |
7503 | #define SQLITE_STATUS_MEMORY_USED 0 |
7504 | #define SQLITE_STATUS_PAGECACHE_USED 1 |
7505 | #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 |
7506 | #define SQLITE_STATUS_SCRATCH_USED 3 /* NOT USED */ |
7507 | #define SQLITE_STATUS_SCRATCH_OVERFLOW 4 /* NOT USED */ |
7508 | #define SQLITE_STATUS_MALLOC_SIZE 5 |
7509 | #define SQLITE_STATUS_PARSER_STACK 6 |
7510 | #define SQLITE_STATUS_PAGECACHE_SIZE 7 |
7511 | #define SQLITE_STATUS_SCRATCH_SIZE 8 /* NOT USED */ |
7512 | #define SQLITE_STATUS_MALLOC_COUNT 9 |
7513 | |
7514 | /* |
7515 | ** CAPI3REF: Database Connection Status |
7516 | ** METHOD: sqlite3 |
7517 | ** |
7518 | ** ^This interface is used to retrieve runtime status information |
7519 | ** about a single [database connection]. ^The first argument is the |
7520 | ** database connection object to be interrogated. ^The second argument |
7521 | ** is an integer constant, taken from the set of |
7522 | ** [SQLITE_DBSTATUS options], that |
7523 | ** determines the parameter to interrogate. The set of |
7524 | ** [SQLITE_DBSTATUS options] is likely |
7525 | ** to grow in future releases of SQLite. |
7526 | ** |
7527 | ** ^The current value of the requested parameter is written into *pCur |
7528 | ** and the highest instantaneous value is written into *pHiwtr. ^If |
7529 | ** the resetFlg is true, then the highest instantaneous value is |
7530 | ** reset back down to the current value. |
7531 | ** |
7532 | ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a |
7533 | ** non-zero [error code] on failure. |
7534 | ** |
7535 | ** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. |
7536 | */ |
7537 | SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); |
7538 | |
7539 | /* |
7540 | ** CAPI3REF: Status Parameters for database connections |
7541 | ** KEYWORDS: {SQLITE_DBSTATUS options} |
7542 | ** |
7543 | ** These constants are the available integer "verbs" that can be passed as |
7544 | ** the second argument to the [sqlite3_db_status()] interface. |
7545 | ** |
7546 | ** New verbs may be added in future releases of SQLite. Existing verbs |
7547 | ** might be discontinued. Applications should check the return code from |
7548 | ** [sqlite3_db_status()] to make sure that the call worked. |
7549 | ** The [sqlite3_db_status()] interface will return a non-zero error code |
7550 | ** if a discontinued or unsupported verb is invoked. |
7551 | ** |
7552 | ** <dl> |
7553 | ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt> |
7554 | ** <dd>This parameter returns the number of lookaside memory slots currently |
7555 | ** checked out.</dd>)^ |
7556 | ** |
7557 | ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt> |
7558 | ** <dd>This parameter returns the number malloc attempts that were |
7559 | ** satisfied using lookaside memory. Only the high-water value is meaningful; |
7560 | ** the current value is always zero.)^ |
7561 | ** |
7562 | ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]] |
7563 | ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt> |
7564 | ** <dd>This parameter returns the number malloc attempts that might have |
7565 | ** been satisfied using lookaside memory but failed due to the amount of |
7566 | ** memory requested being larger than the lookaside slot size. |
7567 | ** Only the high-water value is meaningful; |
7568 | ** the current value is always zero.)^ |
7569 | ** |
7570 | ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]] |
7571 | ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt> |
7572 | ** <dd>This parameter returns the number malloc attempts that might have |
7573 | ** been satisfied using lookaside memory but failed due to all lookaside |
7574 | ** memory already being in use. |
7575 | ** Only the high-water value is meaningful; |
7576 | ** the current value is always zero.)^ |
7577 | ** |
7578 | ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt> |
7579 | ** <dd>This parameter returns the approximate number of bytes of heap |
7580 | ** memory used by all pager caches associated with the database connection.)^ |
7581 | ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0. |
7582 | ** |
7583 | ** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]] |
7584 | ** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt> |
7585 | ** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a |
7586 | ** pager cache is shared between two or more connections the bytes of heap |
7587 | ** memory used by that pager cache is divided evenly between the attached |
7588 | ** connections.)^ In other words, if none of the pager caches associated |
7589 | ** with the database connection are shared, this request returns the same |
7590 | ** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are |
7591 | ** shared, the value returned by this call will be smaller than that returned |
7592 | ** by DBSTATUS_CACHE_USED. ^The highwater mark associated with |
7593 | ** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0. |
7594 | ** |
7595 | ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt> |
7596 | ** <dd>This parameter returns the approximate number of bytes of heap |
7597 | ** memory used to store the schema for all databases associated |
7598 | ** with the connection - main, temp, and any [ATTACH]-ed databases.)^ |
7599 | ** ^The full amount of memory used by the schemas is reported, even if the |
7600 | ** schema memory is shared with other database connections due to |
7601 | ** [shared cache mode] being enabled. |
7602 | ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0. |
7603 | ** |
7604 | ** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt> |
7605 | ** <dd>This parameter returns the approximate number of bytes of heap |
7606 | ** and lookaside memory used by all prepared statements associated with |
7607 | ** the database connection.)^ |
7608 | ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0. |
7609 | ** </dd> |
7610 | ** |
7611 | ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt> |
7612 | ** <dd>This parameter returns the number of pager cache hits that have |
7613 | ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT |
7614 | ** is always 0. |
7615 | ** </dd> |
7616 | ** |
7617 | ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt> |
7618 | ** <dd>This parameter returns the number of pager cache misses that have |
7619 | ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS |
7620 | ** is always 0. |
7621 | ** </dd> |
7622 | ** |
7623 | ** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt> |
7624 | ** <dd>This parameter returns the number of dirty cache entries that have |
7625 | ** been written to disk. Specifically, the number of pages written to the |
7626 | ** wal file in wal mode databases, or the number of pages written to the |
7627 | ** database file in rollback mode databases. Any pages written as part of |
7628 | ** transaction rollback or database recovery operations are not included. |
7629 | ** If an IO or other error occurs while writing a page to disk, the effect |
7630 | ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The |
7631 | ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0. |
7632 | ** </dd> |
7633 | ** |
7634 | ** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt> |
7635 | ** <dd>This parameter returns the number of dirty cache entries that have |
7636 | ** been written to disk in the middle of a transaction due to the page |
7637 | ** cache overflowing. Transactions are more efficient if they are written |
7638 | ** to disk all at once. When pages spill mid-transaction, that introduces |
7639 | ** additional overhead. This parameter can be used help identify |
7640 | ** inefficiencies that can be resolve by increasing the cache size. |
7641 | ** </dd> |
7642 | ** |
7643 | ** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt> |
7644 | ** <dd>This parameter returns zero for the current value if and only if |
7645 | ** all foreign key constraints (deferred or immediate) have been |
7646 | ** resolved.)^ ^The highwater mark is always 0. |
7647 | ** </dd> |
7648 | ** </dl> |
7649 | */ |
7650 | #define SQLITE_DBSTATUS_LOOKASIDE_USED 0 |
7651 | #define SQLITE_DBSTATUS_CACHE_USED 1 |
7652 | #define SQLITE_DBSTATUS_SCHEMA_USED 2 |
7653 | #define SQLITE_DBSTATUS_STMT_USED 3 |
7654 | #define SQLITE_DBSTATUS_LOOKASIDE_HIT 4 |
7655 | #define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5 |
7656 | #define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6 |
7657 | #define SQLITE_DBSTATUS_CACHE_HIT 7 |
7658 | #define SQLITE_DBSTATUS_CACHE_MISS 8 |
7659 | #define SQLITE_DBSTATUS_CACHE_WRITE 9 |
7660 | #define SQLITE_DBSTATUS_DEFERRED_FKS 10 |
7661 | #define SQLITE_DBSTATUS_CACHE_USED_SHARED 11 |
7662 | #define SQLITE_DBSTATUS_CACHE_SPILL 12 |
7663 | #define SQLITE_DBSTATUS_MAX 12 /* Largest defined DBSTATUS */ |
7664 | |
7665 | |
7666 | /* |
7667 | ** CAPI3REF: Prepared Statement Status |
7668 | ** METHOD: sqlite3_stmt |
7669 | ** |
7670 | ** ^(Each prepared statement maintains various |
7671 | ** [SQLITE_STMTSTATUS counters] that measure the number |
7672 | ** of times it has performed specific operations.)^ These counters can |
7673 | ** be used to monitor the performance characteristics of the prepared |
7674 | ** statements. For example, if the number of table steps greatly exceeds |
7675 | ** the number of table searches or result rows, that would tend to indicate |
7676 | ** that the prepared statement is using a full table scan rather than |
7677 | ** an index. |
7678 | ** |
7679 | ** ^(This interface is used to retrieve and reset counter values from |
7680 | ** a [prepared statement]. The first argument is the prepared statement |
7681 | ** object to be interrogated. The second argument |
7682 | ** is an integer code for a specific [SQLITE_STMTSTATUS counter] |
7683 | ** to be interrogated.)^ |
7684 | ** ^The current value of the requested counter is returned. |
7685 | ** ^If the resetFlg is true, then the counter is reset to zero after this |
7686 | ** interface call returns. |
7687 | ** |
7688 | ** See also: [sqlite3_status()] and [sqlite3_db_status()]. |
7689 | */ |
7690 | SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg); |
7691 | |
7692 | /* |
7693 | ** CAPI3REF: Status Parameters for prepared statements |
7694 | ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters} |
7695 | ** |
7696 | ** These preprocessor macros define integer codes that name counter |
7697 | ** values associated with the [sqlite3_stmt_status()] interface. |
7698 | ** The meanings of the various counters are as follows: |
7699 | ** |
7700 | ** <dl> |
7701 | ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt> |
7702 | ** <dd>^This is the number of times that SQLite has stepped forward in |
7703 | ** a table as part of a full table scan. Large numbers for this counter |
7704 | ** may indicate opportunities for performance improvement through |
7705 | ** careful use of indices.</dd> |
7706 | ** |
7707 | ** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt> |
7708 | ** <dd>^This is the number of sort operations that have occurred. |
7709 | ** A non-zero value in this counter may indicate an opportunity to |
7710 | ** improvement performance through careful use of indices.</dd> |
7711 | ** |
7712 | ** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt> |
7713 | ** <dd>^This is the number of rows inserted into transient indices that |
7714 | ** were created automatically in order to help joins run faster. |
7715 | ** A non-zero value in this counter may indicate an opportunity to |
7716 | ** improvement performance by adding permanent indices that do not |
7717 | ** need to be reinitialized each time the statement is run.</dd> |
7718 | ** |
7719 | ** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt> |
7720 | ** <dd>^This is the number of virtual machine operations executed |
7721 | ** by the prepared statement if that number is less than or equal |
7722 | ** to 2147483647. The number of virtual machine operations can be |
7723 | ** used as a proxy for the total work done by the prepared statement. |
7724 | ** If the number of virtual machine operations exceeds 2147483647 |
7725 | ** then the value returned by this statement status code is undefined. |
7726 | ** |
7727 | ** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt> |
7728 | ** <dd>^This is the number of times that the prepare statement has been |
7729 | ** automatically regenerated due to schema changes or change to |
7730 | ** [bound parameters] that might affect the query plan. |
7731 | ** |
7732 | ** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt> |
7733 | ** <dd>^This is the number of times that the prepared statement has |
7734 | ** been run. A single "run" for the purposes of this counter is one |
7735 | ** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()]. |
7736 | ** The counter is incremented on the first [sqlite3_step()] call of each |
7737 | ** cycle. |
7738 | ** |
7739 | ** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt> |
7740 | ** <dd>^This is the approximate number of bytes of heap memory |
7741 | ** used to store the prepared statement. ^This value is not actually |
7742 | ** a counter, and so the resetFlg parameter to sqlite3_stmt_status() |
7743 | ** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED. |
7744 | ** </dd> |
7745 | ** </dl> |
7746 | */ |
7747 | #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 |
7748 | #define SQLITE_STMTSTATUS_SORT 2 |
7749 | #define SQLITE_STMTSTATUS_AUTOINDEX 3 |
7750 | #define SQLITE_STMTSTATUS_VM_STEP 4 |
7751 | #define SQLITE_STMTSTATUS_REPREPARE 5 |
7752 | #define SQLITE_STMTSTATUS_RUN 6 |
7753 | #define SQLITE_STMTSTATUS_MEMUSED 99 |
7754 | |
7755 | /* |
7756 | ** CAPI3REF: Custom Page Cache Object |
7757 | ** |
7758 | ** The sqlite3_pcache type is opaque. It is implemented by |
7759 | ** the pluggable module. The SQLite core has no knowledge of |
7760 | ** its size or internal structure and never deals with the |
7761 | ** sqlite3_pcache object except by holding and passing pointers |
7762 | ** to the object. |
7763 | ** |
7764 | ** See [sqlite3_pcache_methods2] for additional information. |
7765 | */ |
7766 | typedef struct sqlite3_pcache sqlite3_pcache; |
7767 | |
7768 | /* |
7769 | ** CAPI3REF: Custom Page Cache Object |
7770 | ** |
7771 | ** The sqlite3_pcache_page object represents a single page in the |
7772 | ** page cache. The page cache will allocate instances of this |
7773 | ** object. Various methods of the page cache use pointers to instances |
7774 | ** of this object as parameters or as their return value. |
7775 | ** |
7776 | ** See [sqlite3_pcache_methods2] for additional information. |
7777 | */ |
7778 | typedef struct sqlite3_pcache_page sqlite3_pcache_page; |
7779 | struct sqlite3_pcache_page { |
7780 | void *pBuf; /* The content of the page */ |
7781 | void *; /* Extra information associated with the page */ |
7782 | }; |
7783 | |
7784 | /* |
7785 | ** CAPI3REF: Application Defined Page Cache. |
7786 | ** KEYWORDS: {page cache} |
7787 | ** |
7788 | ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can |
7789 | ** register an alternative page cache implementation by passing in an |
7790 | ** instance of the sqlite3_pcache_methods2 structure.)^ |
7791 | ** In many applications, most of the heap memory allocated by |
7792 | ** SQLite is used for the page cache. |
7793 | ** By implementing a |
7794 | ** custom page cache using this API, an application can better control |
7795 | ** the amount of memory consumed by SQLite, the way in which |
7796 | ** that memory is allocated and released, and the policies used to |
7797 | ** determine exactly which parts of a database file are cached and for |
7798 | ** how long. |
7799 | ** |
7800 | ** The alternative page cache mechanism is an |
7801 | ** extreme measure that is only needed by the most demanding applications. |
7802 | ** The built-in page cache is recommended for most uses. |
7803 | ** |
7804 | ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an |
7805 | ** internal buffer by SQLite within the call to [sqlite3_config]. Hence |
7806 | ** the application may discard the parameter after the call to |
7807 | ** [sqlite3_config()] returns.)^ |
7808 | ** |
7809 | ** [[the xInit() page cache method]] |
7810 | ** ^(The xInit() method is called once for each effective |
7811 | ** call to [sqlite3_initialize()])^ |
7812 | ** (usually only once during the lifetime of the process). ^(The xInit() |
7813 | ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^ |
7814 | ** The intent of the xInit() method is to set up global data structures |
7815 | ** required by the custom page cache implementation. |
7816 | ** ^(If the xInit() method is NULL, then the |
7817 | ** built-in default page cache is used instead of the application defined |
7818 | ** page cache.)^ |
7819 | ** |
7820 | ** [[the xShutdown() page cache method]] |
7821 | ** ^The xShutdown() method is called by [sqlite3_shutdown()]. |
7822 | ** It can be used to clean up |
7823 | ** any outstanding resources before process shutdown, if required. |
7824 | ** ^The xShutdown() method may be NULL. |
7825 | ** |
7826 | ** ^SQLite automatically serializes calls to the xInit method, |
7827 | ** so the xInit method need not be threadsafe. ^The |
7828 | ** xShutdown method is only called from [sqlite3_shutdown()] so it does |
7829 | ** not need to be threadsafe either. All other methods must be threadsafe |
7830 | ** in multithreaded applications. |
7831 | ** |
7832 | ** ^SQLite will never invoke xInit() more than once without an intervening |
7833 | ** call to xShutdown(). |
7834 | ** |
7835 | ** [[the xCreate() page cache methods]] |
7836 | ** ^SQLite invokes the xCreate() method to construct a new cache instance. |
7837 | ** SQLite will typically create one cache instance for each open database file, |
7838 | ** though this is not guaranteed. ^The |
7839 | ** first parameter, szPage, is the size in bytes of the pages that must |
7840 | ** be allocated by the cache. ^szPage will always a power of two. ^The |
7841 | ** second parameter szExtra is a number of bytes of extra storage |
7842 | ** associated with each page cache entry. ^The szExtra parameter will |
7843 | ** a number less than 250. SQLite will use the |
7844 | ** extra szExtra bytes on each page to store metadata about the underlying |
7845 | ** database page on disk. The value passed into szExtra depends |
7846 | ** on the SQLite version, the target platform, and how SQLite was compiled. |
7847 | ** ^The third argument to xCreate(), bPurgeable, is true if the cache being |
7848 | ** created will be used to cache database pages of a file stored on disk, or |
7849 | ** false if it is used for an in-memory database. The cache implementation |
7850 | ** does not have to do anything special based with the value of bPurgeable; |
7851 | ** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will |
7852 | ** never invoke xUnpin() except to deliberately delete a page. |
7853 | ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to |
7854 | ** false will always have the "discard" flag set to true. |
7855 | ** ^Hence, a cache created with bPurgeable false will |
7856 | ** never contain any unpinned pages. |
7857 | ** |
7858 | ** [[the xCachesize() page cache method]] |
7859 | ** ^(The xCachesize() method may be called at any time by SQLite to set the |
7860 | ** suggested maximum cache-size (number of pages stored by) the cache |
7861 | ** instance passed as the first argument. This is the value configured using |
7862 | ** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable |
7863 | ** parameter, the implementation is not required to do anything with this |
7864 | ** value; it is advisory only. |
7865 | ** |
7866 | ** [[the xPagecount() page cache methods]] |
7867 | ** The xPagecount() method must return the number of pages currently |
7868 | ** stored in the cache, both pinned and unpinned. |
7869 | ** |
7870 | ** [[the xFetch() page cache methods]] |
7871 | ** The xFetch() method locates a page in the cache and returns a pointer to |
7872 | ** an sqlite3_pcache_page object associated with that page, or a NULL pointer. |
7873 | ** The pBuf element of the returned sqlite3_pcache_page object will be a |
7874 | ** pointer to a buffer of szPage bytes used to store the content of a |
7875 | ** single database page. The pExtra element of sqlite3_pcache_page will be |
7876 | ** a pointer to the szExtra bytes of extra storage that SQLite has requested |
7877 | ** for each entry in the page cache. |
7878 | ** |
7879 | ** The page to be fetched is determined by the key. ^The minimum key value |
7880 | ** is 1. After it has been retrieved using xFetch, the page is considered |
7881 | ** to be "pinned". |
7882 | ** |
7883 | ** If the requested page is already in the page cache, then the page cache |
7884 | ** implementation must return a pointer to the page buffer with its content |
7885 | ** intact. If the requested page is not already in the cache, then the |
7886 | ** cache implementation should use the value of the createFlag |
7887 | ** parameter to help it determined what action to take: |
7888 | ** |
7889 | ** <table border=1 width=85% align=center> |
7890 | ** <tr><th> createFlag <th> Behavior when page is not already in cache |
7891 | ** <tr><td> 0 <td> Do not allocate a new page. Return NULL. |
7892 | ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so. |
7893 | ** Otherwise return NULL. |
7894 | ** <tr><td> 2 <td> Make every effort to allocate a new page. Only return |
7895 | ** NULL if allocating a new page is effectively impossible. |
7896 | ** </table> |
7897 | ** |
7898 | ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite |
7899 | ** will only use a createFlag of 2 after a prior call with a createFlag of 1 |
7900 | ** failed.)^ In between the to xFetch() calls, SQLite may |
7901 | ** attempt to unpin one or more cache pages by spilling the content of |
7902 | ** pinned pages to disk and synching the operating system disk cache. |
7903 | ** |
7904 | ** [[the xUnpin() page cache method]] |
7905 | ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page |
7906 | ** as its second argument. If the third parameter, discard, is non-zero, |
7907 | ** then the page must be evicted from the cache. |
7908 | ** ^If the discard parameter is |
7909 | ** zero, then the page may be discarded or retained at the discretion of |
7910 | ** page cache implementation. ^The page cache implementation |
7911 | ** may choose to evict unpinned pages at any time. |
7912 | ** |
7913 | ** The cache must not perform any reference counting. A single |
7914 | ** call to xUnpin() unpins the page regardless of the number of prior calls |
7915 | ** to xFetch(). |
7916 | ** |
7917 | ** [[the xRekey() page cache methods]] |
7918 | ** The xRekey() method is used to change the key value associated with the |
7919 | ** page passed as the second argument. If the cache |
7920 | ** previously contains an entry associated with newKey, it must be |
7921 | ** discarded. ^Any prior cache entry associated with newKey is guaranteed not |
7922 | ** to be pinned. |
7923 | ** |
7924 | ** When SQLite calls the xTruncate() method, the cache must discard all |
7925 | ** existing cache entries with page numbers (keys) greater than or equal |
7926 | ** to the value of the iLimit parameter passed to xTruncate(). If any |
7927 | ** of these pages are pinned, they are implicitly unpinned, meaning that |
7928 | ** they can be safely discarded. |
7929 | ** |
7930 | ** [[the xDestroy() page cache method]] |
7931 | ** ^The xDestroy() method is used to delete a cache allocated by xCreate(). |
7932 | ** All resources associated with the specified cache should be freed. ^After |
7933 | ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] |
7934 | ** handle invalid, and will not use it with any other sqlite3_pcache_methods2 |
7935 | ** functions. |
7936 | ** |
7937 | ** [[the xShrink() page cache method]] |
7938 | ** ^SQLite invokes the xShrink() method when it wants the page cache to |
7939 | ** free up as much of heap memory as possible. The page cache implementation |
7940 | ** is not obligated to free any memory, but well-behaved implementations should |
7941 | ** do their best. |
7942 | */ |
7943 | typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2; |
7944 | struct sqlite3_pcache_methods2 { |
7945 | int iVersion; |
7946 | void *pArg; |
7947 | int (*xInit)(void*); |
7948 | void (*xShutdown)(void*); |
7949 | sqlite3_pcache *(*xCreate)(int szPage, int , int bPurgeable); |
7950 | void (*xCachesize)(sqlite3_pcache*, int nCachesize); |
7951 | int (*xPagecount)(sqlite3_pcache*); |
7952 | sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); |
7953 | void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard); |
7954 | void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, |
7955 | unsigned oldKey, unsigned newKey); |
7956 | void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); |
7957 | void (*xDestroy)(sqlite3_pcache*); |
7958 | void (*xShrink)(sqlite3_pcache*); |
7959 | }; |
7960 | |
7961 | /* |
7962 | ** This is the obsolete pcache_methods object that has now been replaced |
7963 | ** by sqlite3_pcache_methods2. This object is not used by SQLite. It is |
7964 | ** retained in the header file for backwards compatibility only. |
7965 | */ |
7966 | typedef struct sqlite3_pcache_methods sqlite3_pcache_methods; |
7967 | struct sqlite3_pcache_methods { |
7968 | void *pArg; |
7969 | int (*xInit)(void*); |
7970 | void (*xShutdown)(void*); |
7971 | sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); |
7972 | void (*xCachesize)(sqlite3_pcache*, int nCachesize); |
7973 | int (*xPagecount)(sqlite3_pcache*); |
7974 | void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); |
7975 | void (*xUnpin)(sqlite3_pcache*, void*, int discard); |
7976 | void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); |
7977 | void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); |
7978 | void (*xDestroy)(sqlite3_pcache*); |
7979 | }; |
7980 | |
7981 | |
7982 | /* |
7983 | ** CAPI3REF: Online Backup Object |
7984 | ** |
7985 | ** The sqlite3_backup object records state information about an ongoing |
7986 | ** online backup operation. ^The sqlite3_backup object is created by |
7987 | ** a call to [sqlite3_backup_init()] and is destroyed by a call to |
7988 | ** [sqlite3_backup_finish()]. |
7989 | ** |
7990 | ** See Also: [Using the SQLite Online Backup API] |
7991 | */ |
7992 | typedef struct sqlite3_backup sqlite3_backup; |
7993 | |
7994 | /* |
7995 | ** CAPI3REF: Online Backup API. |
7996 | ** |
7997 | ** The backup API copies the content of one database into another. |
7998 | ** It is useful either for creating backups of databases or |
7999 | ** for copying in-memory databases to or from persistent files. |
8000 | ** |
8001 | ** See Also: [Using the SQLite Online Backup API] |
8002 | ** |
8003 | ** ^SQLite holds a write transaction open on the destination database file |
8004 | ** for the duration of the backup operation. |
8005 | ** ^The source database is read-locked only while it is being read; |
8006 | ** it is not locked continuously for the entire backup operation. |
8007 | ** ^Thus, the backup may be performed on a live source database without |
8008 | ** preventing other database connections from |
8009 | ** reading or writing to the source database while the backup is underway. |
8010 | ** |
8011 | ** ^(To perform a backup operation: |
8012 | ** <ol> |
8013 | ** <li><b>sqlite3_backup_init()</b> is called once to initialize the |
8014 | ** backup, |
8015 | ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer |
8016 | ** the data between the two databases, and finally |
8017 | ** <li><b>sqlite3_backup_finish()</b> is called to release all resources |
8018 | ** associated with the backup operation. |
8019 | ** </ol>)^ |
8020 | ** There should be exactly one call to sqlite3_backup_finish() for each |
8021 | ** successful call to sqlite3_backup_init(). |
8022 | ** |
8023 | ** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b> |
8024 | ** |
8025 | ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the |
8026 | ** [database connection] associated with the destination database |
8027 | ** and the database name, respectively. |
8028 | ** ^The database name is "main" for the main database, "temp" for the |
8029 | ** temporary database, or the name specified after the AS keyword in |
8030 | ** an [ATTACH] statement for an attached database. |
8031 | ** ^The S and M arguments passed to |
8032 | ** sqlite3_backup_init(D,N,S,M) identify the [database connection] |
8033 | ** and database name of the source database, respectively. |
8034 | ** ^The source and destination [database connections] (parameters S and D) |
8035 | ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with |
8036 | ** an error. |
8037 | ** |
8038 | ** ^A call to sqlite3_backup_init() will fail, returning NULL, if |
8039 | ** there is already a read or read-write transaction open on the |
8040 | ** destination database. |
8041 | ** |
8042 | ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is |
8043 | ** returned and an error code and error message are stored in the |
8044 | ** destination [database connection] D. |
8045 | ** ^The error code and message for the failed call to sqlite3_backup_init() |
8046 | ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or |
8047 | ** [sqlite3_errmsg16()] functions. |
8048 | ** ^A successful call to sqlite3_backup_init() returns a pointer to an |
8049 | ** [sqlite3_backup] object. |
8050 | ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and |
8051 | ** sqlite3_backup_finish() functions to perform the specified backup |
8052 | ** operation. |
8053 | ** |
8054 | ** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b> |
8055 | ** |
8056 | ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between |
8057 | ** the source and destination databases specified by [sqlite3_backup] object B. |
8058 | ** ^If N is negative, all remaining source pages are copied. |
8059 | ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there |
8060 | ** are still more pages to be copied, then the function returns [SQLITE_OK]. |
8061 | ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages |
8062 | ** from source to destination, then it returns [SQLITE_DONE]. |
8063 | ** ^If an error occurs while running sqlite3_backup_step(B,N), |
8064 | ** then an [error code] is returned. ^As well as [SQLITE_OK] and |
8065 | ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], |
8066 | ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an |
8067 | ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. |
8068 | ** |
8069 | ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if |
8070 | ** <ol> |
8071 | ** <li> the destination database was opened read-only, or |
8072 | ** <li> the destination database is using write-ahead-log journaling |
8073 | ** and the destination and source page sizes differ, or |
8074 | ** <li> the destination database is an in-memory database and the |
8075 | ** destination and source page sizes differ. |
8076 | ** </ol>)^ |
8077 | ** |
8078 | ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then |
8079 | ** the [sqlite3_busy_handler | busy-handler function] |
8080 | ** is invoked (if one is specified). ^If the |
8081 | ** busy-handler returns non-zero before the lock is available, then |
8082 | ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to |
8083 | ** sqlite3_backup_step() can be retried later. ^If the source |
8084 | ** [database connection] |
8085 | ** is being used to write to the source database when sqlite3_backup_step() |
8086 | ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this |
8087 | ** case the call to sqlite3_backup_step() can be retried later on. ^(If |
8088 | ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or |
8089 | ** [SQLITE_READONLY] is returned, then |
8090 | ** there is no point in retrying the call to sqlite3_backup_step(). These |
8091 | ** errors are considered fatal.)^ The application must accept |
8092 | ** that the backup operation has failed and pass the backup operation handle |
8093 | ** to the sqlite3_backup_finish() to release associated resources. |
8094 | ** |
8095 | ** ^The first call to sqlite3_backup_step() obtains an exclusive lock |
8096 | ** on the destination file. ^The exclusive lock is not released until either |
8097 | ** sqlite3_backup_finish() is called or the backup operation is complete |
8098 | ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to |
8099 | ** sqlite3_backup_step() obtains a [shared lock] on the source database that |
8100 | ** lasts for the duration of the sqlite3_backup_step() call. |
8101 | ** ^Because the source database is not locked between calls to |
8102 | ** sqlite3_backup_step(), the source database may be modified mid-way |
8103 | ** through the backup process. ^If the source database is modified by an |
8104 | ** external process or via a database connection other than the one being |
8105 | ** used by the backup operation, then the backup will be automatically |
8106 | ** restarted by the next call to sqlite3_backup_step(). ^If the source |
8107 | ** database is modified by the using the same database connection as is used |
8108 | ** by the backup operation, then the backup database is automatically |
8109 | ** updated at the same time. |
8110 | ** |
8111 | ** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b> |
8112 | ** |
8113 | ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the |
8114 | ** application wishes to abandon the backup operation, the application |
8115 | ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish(). |
8116 | ** ^The sqlite3_backup_finish() interfaces releases all |
8117 | ** resources associated with the [sqlite3_backup] object. |
8118 | ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any |
8119 | ** active write-transaction on the destination database is rolled back. |
8120 | ** The [sqlite3_backup] object is invalid |
8121 | ** and may not be used following a call to sqlite3_backup_finish(). |
8122 | ** |
8123 | ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no |
8124 | ** sqlite3_backup_step() errors occurred, regardless or whether or not |
8125 | ** sqlite3_backup_step() completed. |
8126 | ** ^If an out-of-memory condition or IO error occurred during any prior |
8127 | ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then |
8128 | ** sqlite3_backup_finish() returns the corresponding [error code]. |
8129 | ** |
8130 | ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() |
8131 | ** is not a permanent error and does not affect the return value of |
8132 | ** sqlite3_backup_finish(). |
8133 | ** |
8134 | ** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]] |
8135 | ** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b> |
8136 | ** |
8137 | ** ^The sqlite3_backup_remaining() routine returns the number of pages still |
8138 | ** to be backed up at the conclusion of the most recent sqlite3_backup_step(). |
8139 | ** ^The sqlite3_backup_pagecount() routine returns the total number of pages |
8140 | ** in the source database at the conclusion of the most recent |
8141 | ** sqlite3_backup_step(). |
8142 | ** ^(The values returned by these functions are only updated by |
8143 | ** sqlite3_backup_step(). If the source database is modified in a way that |
8144 | ** changes the size of the source database or the number of pages remaining, |
8145 | ** those changes are not reflected in the output of sqlite3_backup_pagecount() |
8146 | ** and sqlite3_backup_remaining() until after the next |
8147 | ** sqlite3_backup_step().)^ |
8148 | ** |
8149 | ** <b>Concurrent Usage of Database Handles</b> |
8150 | ** |
8151 | ** ^The source [database connection] may be used by the application for other |
8152 | ** purposes while a backup operation is underway or being initialized. |
8153 | ** ^If SQLite is compiled and configured to support threadsafe database |
8154 | ** connections, then the source database connection may be used concurrently |
8155 | ** from within other threads. |
8156 | ** |
8157 | ** However, the application must guarantee that the destination |
8158 | ** [database connection] is not passed to any other API (by any thread) after |
8159 | ** sqlite3_backup_init() is called and before the corresponding call to |
8160 | ** sqlite3_backup_finish(). SQLite does not currently check to see |
8161 | ** if the application incorrectly accesses the destination [database connection] |
8162 | ** and so no error code is reported, but the operations may malfunction |
8163 | ** nevertheless. Use of the destination database connection while a |
8164 | ** backup is in progress might also also cause a mutex deadlock. |
8165 | ** |
8166 | ** If running in [shared cache mode], the application must |
8167 | ** guarantee that the shared cache used by the destination database |
8168 | ** is not accessed while the backup is running. In practice this means |
8169 | ** that the application must guarantee that the disk file being |
8170 | ** backed up to is not accessed by any connection within the process, |
8171 | ** not just the specific connection that was passed to sqlite3_backup_init(). |
8172 | ** |
8173 | ** The [sqlite3_backup] object itself is partially threadsafe. Multiple |
8174 | ** threads may safely make multiple concurrent calls to sqlite3_backup_step(). |
8175 | ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() |
8176 | ** APIs are not strictly speaking threadsafe. If they are invoked at the |
8177 | ** same time as another thread is invoking sqlite3_backup_step() it is |
8178 | ** possible that they return invalid values. |
8179 | */ |
8180 | SQLITE_API sqlite3_backup *sqlite3_backup_init( |
8181 | sqlite3 *pDest, /* Destination database handle */ |
8182 | const char *zDestName, /* Destination database name */ |
8183 | sqlite3 *pSource, /* Source database handle */ |
8184 | const char *zSourceName /* Source database name */ |
8185 | ); |
8186 | SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage); |
8187 | SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p); |
8188 | SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p); |
8189 | SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p); |
8190 | |
8191 | /* |
8192 | ** CAPI3REF: Unlock Notification |
8193 | ** METHOD: sqlite3 |
8194 | ** |
8195 | ** ^When running in shared-cache mode, a database operation may fail with |
8196 | ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or |
8197 | ** individual tables within the shared-cache cannot be obtained. See |
8198 | ** [SQLite Shared-Cache Mode] for a description of shared-cache locking. |
8199 | ** ^This API may be used to register a callback that SQLite will invoke |
8200 | ** when the connection currently holding the required lock relinquishes it. |
8201 | ** ^This API is only available if the library was compiled with the |
8202 | ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. |
8203 | ** |
8204 | ** See Also: [Using the SQLite Unlock Notification Feature]. |
8205 | ** |
8206 | ** ^Shared-cache locks are released when a database connection concludes |
8207 | ** its current transaction, either by committing it or rolling it back. |
8208 | ** |
8209 | ** ^When a connection (known as the blocked connection) fails to obtain a |
8210 | ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the |
8211 | ** identity of the database connection (the blocking connection) that |
8212 | ** has locked the required resource is stored internally. ^After an |
8213 | ** application receives an SQLITE_LOCKED error, it may call the |
8214 | ** sqlite3_unlock_notify() method with the blocked connection handle as |
8215 | ** the first argument to register for a callback that will be invoked |
8216 | ** when the blocking connections current transaction is concluded. ^The |
8217 | ** callback is invoked from within the [sqlite3_step] or [sqlite3_close] |
8218 | ** call that concludes the blocking connections transaction. |
8219 | ** |
8220 | ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application, |
8221 | ** there is a chance that the blocking connection will have already |
8222 | ** concluded its transaction by the time sqlite3_unlock_notify() is invoked. |
8223 | ** If this happens, then the specified callback is invoked immediately, |
8224 | ** from within the call to sqlite3_unlock_notify().)^ |
8225 | ** |
8226 | ** ^If the blocked connection is attempting to obtain a write-lock on a |
8227 | ** shared-cache table, and more than one other connection currently holds |
8228 | ** a read-lock on the same table, then SQLite arbitrarily selects one of |
8229 | ** the other connections to use as the blocking connection. |
8230 | ** |
8231 | ** ^(There may be at most one unlock-notify callback registered by a |
8232 | ** blocked connection. If sqlite3_unlock_notify() is called when the |
8233 | ** blocked connection already has a registered unlock-notify callback, |
8234 | ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is |
8235 | ** called with a NULL pointer as its second argument, then any existing |
8236 | ** unlock-notify callback is canceled. ^The blocked connections |
8237 | ** unlock-notify callback may also be canceled by closing the blocked |
8238 | ** connection using [sqlite3_close()]. |
8239 | ** |
8240 | ** The unlock-notify callback is not reentrant. If an application invokes |
8241 | ** any sqlite3_xxx API functions from within an unlock-notify callback, a |
8242 | ** crash or deadlock may be the result. |
8243 | ** |
8244 | ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always |
8245 | ** returns SQLITE_OK. |
8246 | ** |
8247 | ** <b>Callback Invocation Details</b> |
8248 | ** |
8249 | ** When an unlock-notify callback is registered, the application provides a |
8250 | ** single void* pointer that is passed to the callback when it is invoked. |
8251 | ** However, the signature of the callback function allows SQLite to pass |
8252 | ** it an array of void* context pointers. The first argument passed to |
8253 | ** an unlock-notify callback is a pointer to an array of void* pointers, |
8254 | ** and the second is the number of entries in the array. |
8255 | ** |
8256 | ** When a blocking connections transaction is concluded, there may be |
8257 | ** more than one blocked connection that has registered for an unlock-notify |
8258 | ** callback. ^If two or more such blocked connections have specified the |
8259 | ** same callback function, then instead of invoking the callback function |
8260 | ** multiple times, it is invoked once with the set of void* context pointers |
8261 | ** specified by the blocked connections bundled together into an array. |
8262 | ** This gives the application an opportunity to prioritize any actions |
8263 | ** related to the set of unblocked database connections. |
8264 | ** |
8265 | ** <b>Deadlock Detection</b> |
8266 | ** |
8267 | ** Assuming that after registering for an unlock-notify callback a |
8268 | ** database waits for the callback to be issued before taking any further |
8269 | ** action (a reasonable assumption), then using this API may cause the |
8270 | ** application to deadlock. For example, if connection X is waiting for |
8271 | ** connection Y's transaction to be concluded, and similarly connection |
8272 | ** Y is waiting on connection X's transaction, then neither connection |
8273 | ** will proceed and the system may remain deadlocked indefinitely. |
8274 | ** |
8275 | ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock |
8276 | ** detection. ^If a given call to sqlite3_unlock_notify() would put the |
8277 | ** system in a deadlocked state, then SQLITE_LOCKED is returned and no |
8278 | ** unlock-notify callback is registered. The system is said to be in |
8279 | ** a deadlocked state if connection A has registered for an unlock-notify |
8280 | ** callback on the conclusion of connection B's transaction, and connection |
8281 | ** B has itself registered for an unlock-notify callback when connection |
8282 | ** A's transaction is concluded. ^Indirect deadlock is also detected, so |
8283 | ** the system is also considered to be deadlocked if connection B has |
8284 | ** registered for an unlock-notify callback on the conclusion of connection |
8285 | ** C's transaction, where connection C is waiting on connection A. ^Any |
8286 | ** number of levels of indirection are allowed. |
8287 | ** |
8288 | ** <b>The "DROP TABLE" Exception</b> |
8289 | ** |
8290 | ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost |
8291 | ** always appropriate to call sqlite3_unlock_notify(). There is however, |
8292 | ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, |
8293 | ** SQLite checks if there are any currently executing SELECT statements |
8294 | ** that belong to the same connection. If there are, SQLITE_LOCKED is |
8295 | ** returned. In this case there is no "blocking connection", so invoking |
8296 | ** sqlite3_unlock_notify() results in the unlock-notify callback being |
8297 | ** invoked immediately. If the application then re-attempts the "DROP TABLE" |
8298 | ** or "DROP INDEX" query, an infinite loop might be the result. |
8299 | ** |
8300 | ** One way around this problem is to check the extended error code returned |
8301 | ** by an sqlite3_step() call. ^(If there is a blocking connection, then the |
8302 | ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in |
8303 | ** the special "DROP TABLE/INDEX" case, the extended error code is just |
8304 | ** SQLITE_LOCKED.)^ |
8305 | */ |
8306 | SQLITE_API int sqlite3_unlock_notify( |
8307 | sqlite3 *pBlocked, /* Waiting connection */ |
8308 | void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ |
8309 | void *pNotifyArg /* Argument to pass to xNotify */ |
8310 | ); |
8311 | |
8312 | |
8313 | /* |
8314 | ** CAPI3REF: String Comparison |
8315 | ** |
8316 | ** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications |
8317 | ** and extensions to compare the contents of two buffers containing UTF-8 |
8318 | ** strings in a case-independent fashion, using the same definition of "case |
8319 | ** independence" that SQLite uses internally when comparing identifiers. |
8320 | */ |
8321 | SQLITE_API int sqlite3_stricmp(const char *, const char *); |
8322 | SQLITE_API int sqlite3_strnicmp(const char *, const char *, int); |
8323 | |
8324 | /* |
8325 | ** CAPI3REF: String Globbing |
8326 | * |
8327 | ** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if |
8328 | ** string X matches the [GLOB] pattern P. |
8329 | ** ^The definition of [GLOB] pattern matching used in |
8330 | ** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the |
8331 | ** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function |
8332 | ** is case sensitive. |
8333 | ** |
8334 | ** Note that this routine returns zero on a match and non-zero if the strings |
8335 | ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. |
8336 | ** |
8337 | ** See also: [sqlite3_strlike()]. |
8338 | */ |
8339 | SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr); |
8340 | |
8341 | /* |
8342 | ** CAPI3REF: String LIKE Matching |
8343 | * |
8344 | ** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if |
8345 | ** string X matches the [LIKE] pattern P with escape character E. |
8346 | ** ^The definition of [LIKE] pattern matching used in |
8347 | ** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E" |
8348 | ** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without |
8349 | ** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0. |
8350 | ** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case |
8351 | ** insensitive - equivalent upper and lower case ASCII characters match |
8352 | ** one another. |
8353 | ** |
8354 | ** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though |
8355 | ** only ASCII characters are case folded. |
8356 | ** |
8357 | ** Note that this routine returns zero on a match and non-zero if the strings |
8358 | ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. |
8359 | ** |
8360 | ** See also: [sqlite3_strglob()]. |
8361 | */ |
8362 | SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc); |
8363 | |
8364 | /* |
8365 | ** CAPI3REF: Error Logging Interface |
8366 | ** |
8367 | ** ^The [sqlite3_log()] interface writes a message into the [error log] |
8368 | ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()]. |
8369 | ** ^If logging is enabled, the zFormat string and subsequent arguments are |
8370 | ** used with [sqlite3_snprintf()] to generate the final output string. |
8371 | ** |
8372 | ** The sqlite3_log() interface is intended for use by extensions such as |
8373 | ** virtual tables, collating functions, and SQL functions. While there is |
8374 | ** nothing to prevent an application from calling sqlite3_log(), doing so |
8375 | ** is considered bad form. |
8376 | ** |
8377 | ** The zFormat string must not be NULL. |
8378 | ** |
8379 | ** To avoid deadlocks and other threading problems, the sqlite3_log() routine |
8380 | ** will not use dynamically allocated memory. The log message is stored in |
8381 | ** a fixed-length buffer on the stack. If the log message is longer than |
8382 | ** a few hundred characters, it will be truncated to the length of the |
8383 | ** buffer. |
8384 | */ |
8385 | SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...); |
8386 | |
8387 | /* |
8388 | ** CAPI3REF: Write-Ahead Log Commit Hook |
8389 | ** METHOD: sqlite3 |
8390 | ** |
8391 | ** ^The [sqlite3_wal_hook()] function is used to register a callback that |
8392 | ** is invoked each time data is committed to a database in wal mode. |
8393 | ** |
8394 | ** ^(The callback is invoked by SQLite after the commit has taken place and |
8395 | ** the associated write-lock on the database released)^, so the implementation |
8396 | ** may read, write or [checkpoint] the database as required. |
8397 | ** |
8398 | ** ^The first parameter passed to the callback function when it is invoked |
8399 | ** is a copy of the third parameter passed to sqlite3_wal_hook() when |
8400 | ** registering the callback. ^The second is a copy of the database handle. |
8401 | ** ^The third parameter is the name of the database that was written to - |
8402 | ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter |
8403 | ** is the number of pages currently in the write-ahead log file, |
8404 | ** including those that were just committed. |
8405 | ** |
8406 | ** The callback function should normally return [SQLITE_OK]. ^If an error |
8407 | ** code is returned, that error will propagate back up through the |
8408 | ** SQLite code base to cause the statement that provoked the callback |
8409 | ** to report an error, though the commit will have still occurred. If the |
8410 | ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value |
8411 | ** that does not correspond to any valid SQLite error code, the results |
8412 | ** are undefined. |
8413 | ** |
8414 | ** A single database handle may have at most a single write-ahead log callback |
8415 | ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any |
8416 | ** previously registered write-ahead log callback. ^Note that the |
8417 | ** [sqlite3_wal_autocheckpoint()] interface and the |
8418 | ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will |
8419 | ** overwrite any prior [sqlite3_wal_hook()] settings. |
8420 | */ |
8421 | SQLITE_API void *sqlite3_wal_hook( |
8422 | sqlite3*, |
8423 | int(*)(void *,sqlite3*,const char*,int), |
8424 | void* |
8425 | ); |
8426 | |
8427 | /* |
8428 | ** CAPI3REF: Configure an auto-checkpoint |
8429 | ** METHOD: sqlite3 |
8430 | ** |
8431 | ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around |
8432 | ** [sqlite3_wal_hook()] that causes any database on [database connection] D |
8433 | ** to automatically [checkpoint] |
8434 | ** after committing a transaction if there are N or |
8435 | ** more frames in the [write-ahead log] file. ^Passing zero or |
8436 | ** a negative value as the nFrame parameter disables automatic |
8437 | ** checkpoints entirely. |
8438 | ** |
8439 | ** ^The callback registered by this function replaces any existing callback |
8440 | ** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback |
8441 | ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism |
8442 | ** configured by this function. |
8443 | ** |
8444 | ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface |
8445 | ** from SQL. |
8446 | ** |
8447 | ** ^Checkpoints initiated by this mechanism are |
8448 | ** [sqlite3_wal_checkpoint_v2|PASSIVE]. |
8449 | ** |
8450 | ** ^Every new [database connection] defaults to having the auto-checkpoint |
8451 | ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT] |
8452 | ** pages. The use of this interface |
8453 | ** is only necessary if the default setting is found to be suboptimal |
8454 | ** for a particular application. |
8455 | */ |
8456 | SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N); |
8457 | |
8458 | /* |
8459 | ** CAPI3REF: Checkpoint a database |
8460 | ** METHOD: sqlite3 |
8461 | ** |
8462 | ** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to |
8463 | ** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^ |
8464 | ** |
8465 | ** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the |
8466 | ** [write-ahead log] for database X on [database connection] D to be |
8467 | ** transferred into the database file and for the write-ahead log to |
8468 | ** be reset. See the [checkpointing] documentation for addition |
8469 | ** information. |
8470 | ** |
8471 | ** This interface used to be the only way to cause a checkpoint to |
8472 | ** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()] |
8473 | ** interface was added. This interface is retained for backwards |
8474 | ** compatibility and as a convenience for applications that need to manually |
8475 | ** start a callback but which do not need the full power (and corresponding |
8476 | ** complication) of [sqlite3_wal_checkpoint_v2()]. |
8477 | */ |
8478 | SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb); |
8479 | |
8480 | /* |
8481 | ** CAPI3REF: Checkpoint a database |
8482 | ** METHOD: sqlite3 |
8483 | ** |
8484 | ** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint |
8485 | ** operation on database X of [database connection] D in mode M. Status |
8486 | ** information is written back into integers pointed to by L and C.)^ |
8487 | ** ^(The M parameter must be a valid [checkpoint mode]:)^ |
8488 | ** |
8489 | ** <dl> |
8490 | ** <dt>SQLITE_CHECKPOINT_PASSIVE<dd> |
8491 | ** ^Checkpoint as many frames as possible without waiting for any database |
8492 | ** readers or writers to finish, then sync the database file if all frames |
8493 | ** in the log were checkpointed. ^The [busy-handler callback] |
8494 | ** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode. |
8495 | ** ^On the other hand, passive mode might leave the checkpoint unfinished |
8496 | ** if there are concurrent readers or writers. |
8497 | ** |
8498 | ** <dt>SQLITE_CHECKPOINT_FULL<dd> |
8499 | ** ^This mode blocks (it invokes the |
8500 | ** [sqlite3_busy_handler|busy-handler callback]) until there is no |
8501 | ** database writer and all readers are reading from the most recent database |
8502 | ** snapshot. ^It then checkpoints all frames in the log file and syncs the |
8503 | ** database file. ^This mode blocks new database writers while it is pending, |
8504 | ** but new database readers are allowed to continue unimpeded. |
8505 | ** |
8506 | ** <dt>SQLITE_CHECKPOINT_RESTART<dd> |
8507 | ** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition |
8508 | ** that after checkpointing the log file it blocks (calls the |
8509 | ** [busy-handler callback]) |
8510 | ** until all readers are reading from the database file only. ^This ensures |
8511 | ** that the next writer will restart the log file from the beginning. |
8512 | ** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new |
8513 | ** database writer attempts while it is pending, but does not impede readers. |
8514 | ** |
8515 | ** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd> |
8516 | ** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the |
8517 | ** addition that it also truncates the log file to zero bytes just prior |
8518 | ** to a successful return. |
8519 | ** </dl> |
8520 | ** |
8521 | ** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in |
8522 | ** the log file or to -1 if the checkpoint could not run because |
8523 | ** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not |
8524 | ** NULL,then *pnCkpt is set to the total number of checkpointed frames in the |
8525 | ** log file (including any that were already checkpointed before the function |
8526 | ** was called) or to -1 if the checkpoint could not run due to an error or |
8527 | ** because the database is not in WAL mode. ^Note that upon successful |
8528 | ** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been |
8529 | ** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero. |
8530 | ** |
8531 | ** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If |
8532 | ** any other process is running a checkpoint operation at the same time, the |
8533 | ** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a |
8534 | ** busy-handler configured, it will not be invoked in this case. |
8535 | ** |
8536 | ** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the |
8537 | ** exclusive "writer" lock on the database file. ^If the writer lock cannot be |
8538 | ** obtained immediately, and a busy-handler is configured, it is invoked and |
8539 | ** the writer lock retried until either the busy-handler returns 0 or the lock |
8540 | ** is successfully obtained. ^The busy-handler is also invoked while waiting for |
8541 | ** database readers as described above. ^If the busy-handler returns 0 before |
8542 | ** the writer lock is obtained or while waiting for database readers, the |
8543 | ** checkpoint operation proceeds from that point in the same way as |
8544 | ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible |
8545 | ** without blocking any further. ^SQLITE_BUSY is returned in this case. |
8546 | ** |
8547 | ** ^If parameter zDb is NULL or points to a zero length string, then the |
8548 | ** specified operation is attempted on all WAL databases [attached] to |
8549 | ** [database connection] db. In this case the |
8550 | ** values written to output parameters *pnLog and *pnCkpt are undefined. ^If |
8551 | ** an SQLITE_BUSY error is encountered when processing one or more of the |
8552 | ** attached WAL databases, the operation is still attempted on any remaining |
8553 | ** attached databases and SQLITE_BUSY is returned at the end. ^If any other |
8554 | ** error occurs while processing an attached database, processing is abandoned |
8555 | ** and the error code is returned to the caller immediately. ^If no error |
8556 | ** (SQLITE_BUSY or otherwise) is encountered while processing the attached |
8557 | ** databases, SQLITE_OK is returned. |
8558 | ** |
8559 | ** ^If database zDb is the name of an attached database that is not in WAL |
8560 | ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If |
8561 | ** zDb is not NULL (or a zero length string) and is not the name of any |
8562 | ** attached database, SQLITE_ERROR is returned to the caller. |
8563 | ** |
8564 | ** ^Unless it returns SQLITE_MISUSE, |
8565 | ** the sqlite3_wal_checkpoint_v2() interface |
8566 | ** sets the error information that is queried by |
8567 | ** [sqlite3_errcode()] and [sqlite3_errmsg()]. |
8568 | ** |
8569 | ** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface |
8570 | ** from SQL. |
8571 | */ |
8572 | SQLITE_API int sqlite3_wal_checkpoint_v2( |
8573 | sqlite3 *db, /* Database handle */ |
8574 | const char *zDb, /* Name of attached database (or NULL) */ |
8575 | int eMode, /* SQLITE_CHECKPOINT_* value */ |
8576 | int *pnLog, /* OUT: Size of WAL log in frames */ |
8577 | int *pnCkpt /* OUT: Total number of frames checkpointed */ |
8578 | ); |
8579 | |
8580 | /* |
8581 | ** CAPI3REF: Checkpoint Mode Values |
8582 | ** KEYWORDS: {checkpoint mode} |
8583 | ** |
8584 | ** These constants define all valid values for the "checkpoint mode" passed |
8585 | ** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface. |
8586 | ** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the |
8587 | ** meaning of each of these checkpoint modes. |
8588 | */ |
8589 | #define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */ |
8590 | #define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */ |
8591 | #define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for for readers */ |
8592 | #define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */ |
8593 | |
8594 | /* |
8595 | ** CAPI3REF: Virtual Table Interface Configuration |
8596 | ** |
8597 | ** This function may be called by either the [xConnect] or [xCreate] method |
8598 | ** of a [virtual table] implementation to configure |
8599 | ** various facets of the virtual table interface. |
8600 | ** |
8601 | ** If this interface is invoked outside the context of an xConnect or |
8602 | ** xCreate virtual table method then the behavior is undefined. |
8603 | ** |
8604 | ** At present, there is only one option that may be configured using |
8605 | ** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].) Further options |
8606 | ** may be added in the future. |
8607 | */ |
8608 | SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...); |
8609 | |
8610 | /* |
8611 | ** CAPI3REF: Virtual Table Configuration Options |
8612 | ** |
8613 | ** These macros define the various options to the |
8614 | ** [sqlite3_vtab_config()] interface that [virtual table] implementations |
8615 | ** can use to customize and optimize their behavior. |
8616 | ** |
8617 | ** <dl> |
8618 | ** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT |
8619 | ** <dd>Calls of the form |
8620 | ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported, |
8621 | ** where X is an integer. If X is zero, then the [virtual table] whose |
8622 | ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not |
8623 | ** support constraints. In this configuration (which is the default) if |
8624 | ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire |
8625 | ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been |
8626 | ** specified as part of the users SQL statement, regardless of the actual |
8627 | ** ON CONFLICT mode specified. |
8628 | ** |
8629 | ** If X is non-zero, then the virtual table implementation guarantees |
8630 | ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before |
8631 | ** any modifications to internal or persistent data structures have been made. |
8632 | ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite |
8633 | ** is able to roll back a statement or database transaction, and abandon |
8634 | ** or continue processing the current SQL statement as appropriate. |
8635 | ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns |
8636 | ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode |
8637 | ** had been ABORT. |
8638 | ** |
8639 | ** Virtual table implementations that are required to handle OR REPLACE |
8640 | ** must do so within the [xUpdate] method. If a call to the |
8641 | ** [sqlite3_vtab_on_conflict()] function indicates that the current ON |
8642 | ** CONFLICT policy is REPLACE, the virtual table implementation should |
8643 | ** silently replace the appropriate rows within the xUpdate callback and |
8644 | ** return SQLITE_OK. Or, if this is not possible, it may return |
8645 | ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT |
8646 | ** constraint handling. |
8647 | ** </dl> |
8648 | */ |
8649 | #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1 |
8650 | |
8651 | /* |
8652 | ** CAPI3REF: Determine The Virtual Table Conflict Policy |
8653 | ** |
8654 | ** This function may only be called from within a call to the [xUpdate] method |
8655 | ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The |
8656 | ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL], |
8657 | ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode |
8658 | ** of the SQL statement that triggered the call to the [xUpdate] method of the |
8659 | ** [virtual table]. |
8660 | */ |
8661 | SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *); |
8662 | |
8663 | /* |
8664 | ** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE |
8665 | ** |
8666 | ** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn] |
8667 | ** method of a [virtual table], then it returns true if and only if the |
8668 | ** column is being fetched as part of an UPDATE operation during which the |
8669 | ** column value will not change. Applications might use this to substitute |
8670 | ** a return value that is less expensive to compute and that the corresponding |
8671 | ** [xUpdate] method understands as a "no-change" value. |
8672 | ** |
8673 | ** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that |
8674 | ** the column is not changed by the UPDATE statement, then the xColumn |
8675 | ** method can optionally return without setting a result, without calling |
8676 | ** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces]. |
8677 | ** In that case, [sqlite3_value_nochange(X)] will return true for the |
8678 | ** same column in the [xUpdate] method. |
8679 | */ |
8680 | SQLITE_API int sqlite3_vtab_nochange(sqlite3_context*); |
8681 | |
8682 | /* |
8683 | ** CAPI3REF: Determine The Collation For a Virtual Table Constraint |
8684 | ** |
8685 | ** This function may only be called from within a call to the [xBestIndex] |
8686 | ** method of a [virtual table]. |
8687 | ** |
8688 | ** The first argument must be the sqlite3_index_info object that is the |
8689 | ** first parameter to the xBestIndex() method. The second argument must be |
8690 | ** an index into the aConstraint[] array belonging to the sqlite3_index_info |
8691 | ** structure passed to xBestIndex. This function returns a pointer to a buffer |
8692 | ** containing the name of the collation sequence for the corresponding |
8693 | ** constraint. |
8694 | */ |
8695 | SQLITE_API SQLITE_EXPERIMENTAL const char *sqlite3_vtab_collation(sqlite3_index_info*,int); |
8696 | |
8697 | /* |
8698 | ** CAPI3REF: Conflict resolution modes |
8699 | ** KEYWORDS: {conflict resolution mode} |
8700 | ** |
8701 | ** These constants are returned by [sqlite3_vtab_on_conflict()] to |
8702 | ** inform a [virtual table] implementation what the [ON CONFLICT] mode |
8703 | ** is for the SQL statement being evaluated. |
8704 | ** |
8705 | ** Note that the [SQLITE_IGNORE] constant is also used as a potential |
8706 | ** return value from the [sqlite3_set_authorizer()] callback and that |
8707 | ** [SQLITE_ABORT] is also a [result code]. |
8708 | */ |
8709 | #define SQLITE_ROLLBACK 1 |
8710 | /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */ |
8711 | #define SQLITE_FAIL 3 |
8712 | /* #define SQLITE_ABORT 4 // Also an error code */ |
8713 | #define SQLITE_REPLACE 5 |
8714 | |
8715 | /* |
8716 | ** CAPI3REF: Prepared Statement Scan Status Opcodes |
8717 | ** KEYWORDS: {scanstatus options} |
8718 | ** |
8719 | ** The following constants can be used for the T parameter to the |
8720 | ** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a |
8721 | ** different metric for sqlite3_stmt_scanstatus() to return. |
8722 | ** |
8723 | ** When the value returned to V is a string, space to hold that string is |
8724 | ** managed by the prepared statement S and will be automatically freed when |
8725 | ** S is finalized. |
8726 | ** |
8727 | ** <dl> |
8728 | ** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt> |
8729 | ** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be |
8730 | ** set to the total number of times that the X-th loop has run.</dd> |
8731 | ** |
8732 | ** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt> |
8733 | ** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be set |
8734 | ** to the total number of rows examined by all iterations of the X-th loop.</dd> |
8735 | ** |
8736 | ** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt> |
8737 | ** <dd>^The "double" variable pointed to by the T parameter will be set to the |
8738 | ** query planner's estimate for the average number of rows output from each |
8739 | ** iteration of the X-th loop. If the query planner's estimates was accurate, |
8740 | ** then this value will approximate the quotient NVISIT/NLOOP and the |
8741 | ** product of this value for all prior loops with the same SELECTID will |
8742 | ** be the NLOOP value for the current loop. |
8743 | ** |
8744 | ** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt> |
8745 | ** <dd>^The "const char *" variable pointed to by the T parameter will be set |
8746 | ** to a zero-terminated UTF-8 string containing the name of the index or table |
8747 | ** used for the X-th loop. |
8748 | ** |
8749 | ** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt> |
8750 | ** <dd>^The "const char *" variable pointed to by the T parameter will be set |
8751 | ** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN] |
8752 | ** description for the X-th loop. |
8753 | ** |
8754 | ** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt> |
8755 | ** <dd>^The "int" variable pointed to by the T parameter will be set to the |
8756 | ** "select-id" for the X-th loop. The select-id identifies which query or |
8757 | ** subquery the loop is part of. The main query has a select-id of zero. |
8758 | ** The select-id is the same value as is output in the first column |
8759 | ** of an [EXPLAIN QUERY PLAN] query. |
8760 | ** </dl> |
8761 | */ |
8762 | #define SQLITE_SCANSTAT_NLOOP 0 |
8763 | #define SQLITE_SCANSTAT_NVISIT 1 |
8764 | #define SQLITE_SCANSTAT_EST 2 |
8765 | #define SQLITE_SCANSTAT_NAME 3 |
8766 | #define SQLITE_SCANSTAT_EXPLAIN 4 |
8767 | #define SQLITE_SCANSTAT_SELECTID 5 |
8768 | |
8769 | /* |
8770 | ** CAPI3REF: Prepared Statement Scan Status |
8771 | ** METHOD: sqlite3_stmt |
8772 | ** |
8773 | ** This interface returns information about the predicted and measured |
8774 | ** performance for pStmt. Advanced applications can use this |
8775 | ** interface to compare the predicted and the measured performance and |
8776 | ** issue warnings and/or rerun [ANALYZE] if discrepancies are found. |
8777 | ** |
8778 | ** Since this interface is expected to be rarely used, it is only |
8779 | ** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS] |
8780 | ** compile-time option. |
8781 | ** |
8782 | ** The "iScanStatusOp" parameter determines which status information to return. |
8783 | ** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior |
8784 | ** of this interface is undefined. |
8785 | ** ^The requested measurement is written into a variable pointed to by |
8786 | ** the "pOut" parameter. |
8787 | ** Parameter "idx" identifies the specific loop to retrieve statistics for. |
8788 | ** Loops are numbered starting from zero. ^If idx is out of range - less than |
8789 | ** zero or greater than or equal to the total number of loops used to implement |
8790 | ** the statement - a non-zero value is returned and the variable that pOut |
8791 | ** points to is unchanged. |
8792 | ** |
8793 | ** ^Statistics might not be available for all loops in all statements. ^In cases |
8794 | ** where there exist loops with no available statistics, this function behaves |
8795 | ** as if the loop did not exist - it returns non-zero and leave the variable |
8796 | ** that pOut points to unchanged. |
8797 | ** |
8798 | ** See also: [sqlite3_stmt_scanstatus_reset()] |
8799 | */ |
8800 | SQLITE_API int sqlite3_stmt_scanstatus( |
8801 | sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ |
8802 | int idx, /* Index of loop to report on */ |
8803 | int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ |
8804 | void *pOut /* Result written here */ |
8805 | ); |
8806 | |
8807 | /* |
8808 | ** CAPI3REF: Zero Scan-Status Counters |
8809 | ** METHOD: sqlite3_stmt |
8810 | ** |
8811 | ** ^Zero all [sqlite3_stmt_scanstatus()] related event counters. |
8812 | ** |
8813 | ** This API is only available if the library is built with pre-processor |
8814 | ** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. |
8815 | */ |
8816 | SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); |
8817 | |
8818 | /* |
8819 | ** CAPI3REF: Flush caches to disk mid-transaction |
8820 | ** |
8821 | ** ^If a write-transaction is open on [database connection] D when the |
8822 | ** [sqlite3_db_cacheflush(D)] interface invoked, any dirty |
8823 | ** pages in the pager-cache that are not currently in use are written out |
8824 | ** to disk. A dirty page may be in use if a database cursor created by an |
8825 | ** active SQL statement is reading from it, or if it is page 1 of a database |
8826 | ** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)] |
8827 | ** interface flushes caches for all schemas - "main", "temp", and |
8828 | ** any [attached] databases. |
8829 | ** |
8830 | ** ^If this function needs to obtain extra database locks before dirty pages |
8831 | ** can be flushed to disk, it does so. ^If those locks cannot be obtained |
8832 | ** immediately and there is a busy-handler callback configured, it is invoked |
8833 | ** in the usual manner. ^If the required lock still cannot be obtained, then |
8834 | ** the database is skipped and an attempt made to flush any dirty pages |
8835 | ** belonging to the next (if any) database. ^If any databases are skipped |
8836 | ** because locks cannot be obtained, but no other error occurs, this |
8837 | ** function returns SQLITE_BUSY. |
8838 | ** |
8839 | ** ^If any other error occurs while flushing dirty pages to disk (for |
8840 | ** example an IO error or out-of-memory condition), then processing is |
8841 | ** abandoned and an SQLite [error code] is returned to the caller immediately. |
8842 | ** |
8843 | ** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK. |
8844 | ** |
8845 | ** ^This function does not set the database handle error code or message |
8846 | ** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions. |
8847 | */ |
8848 | SQLITE_API int sqlite3_db_cacheflush(sqlite3*); |
8849 | |
8850 | /* |
8851 | ** CAPI3REF: The pre-update hook. |
8852 | ** |
8853 | ** ^These interfaces are only available if SQLite is compiled using the |
8854 | ** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option. |
8855 | ** |
8856 | ** ^The [sqlite3_preupdate_hook()] interface registers a callback function |
8857 | ** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation |
8858 | ** on a database table. |
8859 | ** ^At most one preupdate hook may be registered at a time on a single |
8860 | ** [database connection]; each call to [sqlite3_preupdate_hook()] overrides |
8861 | ** the previous setting. |
8862 | ** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()] |
8863 | ** with a NULL pointer as the second parameter. |
8864 | ** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as |
8865 | ** the first parameter to callbacks. |
8866 | ** |
8867 | ** ^The preupdate hook only fires for changes to real database tables; the |
8868 | ** preupdate hook is not invoked for changes to [virtual tables] or to |
8869 | ** system tables like sqlite_master or sqlite_stat1. |
8870 | ** |
8871 | ** ^The second parameter to the preupdate callback is a pointer to |
8872 | ** the [database connection] that registered the preupdate hook. |
8873 | ** ^The third parameter to the preupdate callback is one of the constants |
8874 | ** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the |
8875 | ** kind of update operation that is about to occur. |
8876 | ** ^(The fourth parameter to the preupdate callback is the name of the |
8877 | ** database within the database connection that is being modified. This |
8878 | ** will be "main" for the main database or "temp" for TEMP tables or |
8879 | ** the name given after the AS keyword in the [ATTACH] statement for attached |
8880 | ** databases.)^ |
8881 | ** ^The fifth parameter to the preupdate callback is the name of the |
8882 | ** table that is being modified. |
8883 | ** |
8884 | ** For an UPDATE or DELETE operation on a [rowid table], the sixth |
8885 | ** parameter passed to the preupdate callback is the initial [rowid] of the |
8886 | ** row being modified or deleted. For an INSERT operation on a rowid table, |
8887 | ** or any operation on a WITHOUT ROWID table, the value of the sixth |
8888 | ** parameter is undefined. For an INSERT or UPDATE on a rowid table the |
8889 | ** seventh parameter is the final rowid value of the row being inserted |
8890 | ** or updated. The value of the seventh parameter passed to the callback |
8891 | ** function is not defined for operations on WITHOUT ROWID tables, or for |
8892 | ** INSERT operations on rowid tables. |
8893 | ** |
8894 | ** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()], |
8895 | ** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces |
8896 | ** provide additional information about a preupdate event. These routines |
8897 | ** may only be called from within a preupdate callback. Invoking any of |
8898 | ** these routines from outside of a preupdate callback or with a |
8899 | ** [database connection] pointer that is different from the one supplied |
8900 | ** to the preupdate callback results in undefined and probably undesirable |
8901 | ** behavior. |
8902 | ** |
8903 | ** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns |
8904 | ** in the row that is being inserted, updated, or deleted. |
8905 | ** |
8906 | ** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to |
8907 | ** a [protected sqlite3_value] that contains the value of the Nth column of |
8908 | ** the table row before it is updated. The N parameter must be between 0 |
8909 | ** and one less than the number of columns or the behavior will be |
8910 | ** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE |
8911 | ** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the |
8912 | ** behavior is undefined. The [sqlite3_value] that P points to |
8913 | ** will be destroyed when the preupdate callback returns. |
8914 | ** |
8915 | ** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to |
8916 | ** a [protected sqlite3_value] that contains the value of the Nth column of |
8917 | ** the table row after it is updated. The N parameter must be between 0 |
8918 | ** and one less than the number of columns or the behavior will be |
8919 | ** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE |
8920 | ** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the |
8921 | ** behavior is undefined. The [sqlite3_value] that P points to |
8922 | ** will be destroyed when the preupdate callback returns. |
8923 | ** |
8924 | ** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate |
8925 | ** callback was invoked as a result of a direct insert, update, or delete |
8926 | ** operation; or 1 for inserts, updates, or deletes invoked by top-level |
8927 | ** triggers; or 2 for changes resulting from triggers called by top-level |
8928 | ** triggers; and so forth. |
8929 | ** |
8930 | ** See also: [sqlite3_update_hook()] |
8931 | */ |
8932 | #if defined(SQLITE_ENABLE_PREUPDATE_HOOK) |
8933 | SQLITE_API void *sqlite3_preupdate_hook( |
8934 | sqlite3 *db, |
8935 | void(*xPreUpdate)( |
8936 | void *pCtx, /* Copy of third arg to preupdate_hook() */ |
8937 | sqlite3 *db, /* Database handle */ |
8938 | int op, /* SQLITE_UPDATE, DELETE or INSERT */ |
8939 | char const *zDb, /* Database name */ |
8940 | char const *zName, /* Table name */ |
8941 | sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */ |
8942 | sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */ |
8943 | ), |
8944 | void* |
8945 | ); |
8946 | SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **); |
8947 | SQLITE_API int sqlite3_preupdate_count(sqlite3 *); |
8948 | SQLITE_API int sqlite3_preupdate_depth(sqlite3 *); |
8949 | SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **); |
8950 | #endif |
8951 | |
8952 | /* |
8953 | ** CAPI3REF: Low-level system error code |
8954 | ** |
8955 | ** ^Attempt to return the underlying operating system error code or error |
8956 | ** number that caused the most recent I/O error or failure to open a file. |
8957 | ** The return value is OS-dependent. For example, on unix systems, after |
8958 | ** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be |
8959 | ** called to get back the underlying "errno" that caused the problem, such |
8960 | ** as ENOSPC, EAUTH, EISDIR, and so forth. |
8961 | */ |
8962 | SQLITE_API int sqlite3_system_errno(sqlite3*); |
8963 | |
8964 | /* |
8965 | ** CAPI3REF: Database Snapshot |
8966 | ** KEYWORDS: {snapshot} {sqlite3_snapshot} |
8967 | ** |
8968 | ** An instance of the snapshot object records the state of a [WAL mode] |
8969 | ** database for some specific point in history. |
8970 | ** |
8971 | ** In [WAL mode], multiple [database connections] that are open on the |
8972 | ** same database file can each be reading a different historical version |
8973 | ** of the database file. When a [database connection] begins a read |
8974 | ** transaction, that connection sees an unchanging copy of the database |
8975 | ** as it existed for the point in time when the transaction first started. |
8976 | ** Subsequent changes to the database from other connections are not seen |
8977 | ** by the reader until a new read transaction is started. |
8978 | ** |
8979 | ** The sqlite3_snapshot object records state information about an historical |
8980 | ** version of the database file so that it is possible to later open a new read |
8981 | ** transaction that sees that historical version of the database rather than |
8982 | ** the most recent version. |
8983 | */ |
8984 | typedef struct sqlite3_snapshot { |
8985 | unsigned char hidden[48]; |
8986 | } sqlite3_snapshot; |
8987 | |
8988 | /* |
8989 | ** CAPI3REF: Record A Database Snapshot |
8990 | ** CONSTRUCTOR: sqlite3_snapshot |
8991 | ** |
8992 | ** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a |
8993 | ** new [sqlite3_snapshot] object that records the current state of |
8994 | ** schema S in database connection D. ^On success, the |
8995 | ** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly |
8996 | ** created [sqlite3_snapshot] object into *P and returns SQLITE_OK. |
8997 | ** If there is not already a read-transaction open on schema S when |
8998 | ** this function is called, one is opened automatically. |
8999 | ** |
9000 | ** The following must be true for this function to succeed. If any of |
9001 | ** the following statements are false when sqlite3_snapshot_get() is |
9002 | ** called, SQLITE_ERROR is returned. The final value of *P is undefined |
9003 | ** in this case. |
9004 | ** |
9005 | ** <ul> |
9006 | ** <li> The database handle must not be in [autocommit mode]. |
9007 | ** |
9008 | ** <li> Schema S of [database connection] D must be a [WAL mode] database. |
9009 | ** |
9010 | ** <li> There must not be a write transaction open on schema S of database |
9011 | ** connection D. |
9012 | ** |
9013 | ** <li> One or more transactions must have been written to the current wal |
9014 | ** file since it was created on disk (by any connection). This means |
9015 | ** that a snapshot cannot be taken on a wal mode database with no wal |
9016 | ** file immediately after it is first opened. At least one transaction |
9017 | ** must be written to it first. |
9018 | ** </ul> |
9019 | ** |
9020 | ** This function may also return SQLITE_NOMEM. If it is called with the |
9021 | ** database handle in autocommit mode but fails for some other reason, |
9022 | ** whether or not a read transaction is opened on schema S is undefined. |
9023 | ** |
9024 | ** The [sqlite3_snapshot] object returned from a successful call to |
9025 | ** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()] |
9026 | ** to avoid a memory leak. |
9027 | ** |
9028 | ** The [sqlite3_snapshot_get()] interface is only available when the |
9029 | ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. |
9030 | */ |
9031 | SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get( |
9032 | sqlite3 *db, |
9033 | const char *zSchema, |
9034 | sqlite3_snapshot **ppSnapshot |
9035 | ); |
9036 | |
9037 | /* |
9038 | ** CAPI3REF: Start a read transaction on an historical snapshot |
9039 | ** METHOD: sqlite3_snapshot |
9040 | ** |
9041 | ** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read |
9042 | ** transaction or upgrades an existing one for schema S of |
9043 | ** [database connection] D such that the read transaction refers to |
9044 | ** historical [snapshot] P, rather than the most recent change to the |
9045 | ** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK |
9046 | ** on success or an appropriate [error code] if it fails. |
9047 | ** |
9048 | ** ^In order to succeed, the database connection must not be in |
9049 | ** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there |
9050 | ** is already a read transaction open on schema S, then the database handle |
9051 | ** must have no active statements (SELECT statements that have been passed |
9052 | ** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()). |
9053 | ** SQLITE_ERROR is returned if either of these conditions is violated, or |
9054 | ** if schema S does not exist, or if the snapshot object is invalid. |
9055 | ** |
9056 | ** ^A call to sqlite3_snapshot_open() will fail to open if the specified |
9057 | ** snapshot has been overwritten by a [checkpoint]. In this case |
9058 | ** SQLITE_ERROR_SNAPSHOT is returned. |
9059 | ** |
9060 | ** If there is already a read transaction open when this function is |
9061 | ** invoked, then the same read transaction remains open (on the same |
9062 | ** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT |
9063 | ** is returned. If another error code - for example SQLITE_PROTOCOL or an |
9064 | ** SQLITE_IOERR error code - is returned, then the final state of the |
9065 | ** read transaction is undefined. If SQLITE_OK is returned, then the |
9066 | ** read transaction is now open on database snapshot P. |
9067 | ** |
9068 | ** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the |
9069 | ** database connection D does not know that the database file for |
9070 | ** schema S is in [WAL mode]. A database connection might not know |
9071 | ** that the database file is in [WAL mode] if there has been no prior |
9072 | ** I/O on that database connection, or if the database entered [WAL mode] |
9073 | ** after the most recent I/O on the database connection.)^ |
9074 | ** (Hint: Run "[PRAGMA application_id]" against a newly opened |
9075 | ** database connection in order to make it ready to use snapshots.) |
9076 | ** |
9077 | ** The [sqlite3_snapshot_open()] interface is only available when the |
9078 | ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. |
9079 | */ |
9080 | SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open( |
9081 | sqlite3 *db, |
9082 | const char *zSchema, |
9083 | sqlite3_snapshot *pSnapshot |
9084 | ); |
9085 | |
9086 | /* |
9087 | ** CAPI3REF: Destroy a snapshot |
9088 | ** DESTRUCTOR: sqlite3_snapshot |
9089 | ** |
9090 | ** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P. |
9091 | ** The application must eventually free every [sqlite3_snapshot] object |
9092 | ** using this routine to avoid a memory leak. |
9093 | ** |
9094 | ** The [sqlite3_snapshot_free()] interface is only available when the |
9095 | ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. |
9096 | */ |
9097 | SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*); |
9098 | |
9099 | /* |
9100 | ** CAPI3REF: Compare the ages of two snapshot handles. |
9101 | ** METHOD: sqlite3_snapshot |
9102 | ** |
9103 | ** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages |
9104 | ** of two valid snapshot handles. |
9105 | ** |
9106 | ** If the two snapshot handles are not associated with the same database |
9107 | ** file, the result of the comparison is undefined. |
9108 | ** |
9109 | ** Additionally, the result of the comparison is only valid if both of the |
9110 | ** snapshot handles were obtained by calling sqlite3_snapshot_get() since the |
9111 | ** last time the wal file was deleted. The wal file is deleted when the |
9112 | ** database is changed back to rollback mode or when the number of database |
9113 | ** clients drops to zero. If either snapshot handle was obtained before the |
9114 | ** wal file was last deleted, the value returned by this function |
9115 | ** is undefined. |
9116 | ** |
9117 | ** Otherwise, this API returns a negative value if P1 refers to an older |
9118 | ** snapshot than P2, zero if the two handles refer to the same database |
9119 | ** snapshot, and a positive value if P1 is a newer snapshot than P2. |
9120 | ** |
9121 | ** This interface is only available if SQLite is compiled with the |
9122 | ** [SQLITE_ENABLE_SNAPSHOT] option. |
9123 | */ |
9124 | SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp( |
9125 | sqlite3_snapshot *p1, |
9126 | sqlite3_snapshot *p2 |
9127 | ); |
9128 | |
9129 | /* |
9130 | ** CAPI3REF: Recover snapshots from a wal file |
9131 | ** METHOD: sqlite3_snapshot |
9132 | ** |
9133 | ** If a [WAL file] remains on disk after all database connections close |
9134 | ** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control] |
9135 | ** or because the last process to have the database opened exited without |
9136 | ** calling [sqlite3_close()]) and a new connection is subsequently opened |
9137 | ** on that database and [WAL file], the [sqlite3_snapshot_open()] interface |
9138 | ** will only be able to open the last transaction added to the WAL file |
9139 | ** even though the WAL file contains other valid transactions. |
9140 | ** |
9141 | ** This function attempts to scan the WAL file associated with database zDb |
9142 | ** of database handle db and make all valid snapshots available to |
9143 | ** sqlite3_snapshot_open(). It is an error if there is already a read |
9144 | ** transaction open on the database, or if the database is not a WAL mode |
9145 | ** database. |
9146 | ** |
9147 | ** SQLITE_OK is returned if successful, or an SQLite error code otherwise. |
9148 | ** |
9149 | ** This interface is only available if SQLite is compiled with the |
9150 | ** [SQLITE_ENABLE_SNAPSHOT] option. |
9151 | */ |
9152 | SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb); |
9153 | |
9154 | /* |
9155 | ** CAPI3REF: Serialize a database |
9156 | ** |
9157 | ** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory |
9158 | ** that is a serialization of the S database on [database connection] D. |
9159 | ** If P is not a NULL pointer, then the size of the database in bytes |
9160 | ** is written into *P. |
9161 | ** |
9162 | ** For an ordinary on-disk database file, the serialization is just a |
9163 | ** copy of the disk file. For an in-memory database or a "TEMP" database, |
9164 | ** the serialization is the same sequence of bytes which would be written |
9165 | ** to disk if that database where backed up to disk. |
9166 | ** |
9167 | ** The usual case is that sqlite3_serialize() copies the serialization of |
9168 | ** the database into memory obtained from [sqlite3_malloc64()] and returns |
9169 | ** a pointer to that memory. The caller is responsible for freeing the |
9170 | ** returned value to avoid a memory leak. However, if the F argument |
9171 | ** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations |
9172 | ** are made, and the sqlite3_serialize() function will return a pointer |
9173 | ** to the contiguous memory representation of the database that SQLite |
9174 | ** is currently using for that database, or NULL if the no such contiguous |
9175 | ** memory representation of the database exists. A contiguous memory |
9176 | ** representation of the database will usually only exist if there has |
9177 | ** been a prior call to [sqlite3_deserialize(D,S,...)] with the same |
9178 | ** values of D and S. |
9179 | ** The size of the database is written into *P even if the |
9180 | ** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy |
9181 | ** of the database exists. |
9182 | ** |
9183 | ** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the |
9184 | ** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory |
9185 | ** allocation error occurs. |
9186 | ** |
9187 | ** This interface is only available if SQLite is compiled with the |
9188 | ** [SQLITE_ENABLE_DESERIALIZE] option. |
9189 | */ |
9190 | SQLITE_API unsigned char *sqlite3_serialize( |
9191 | sqlite3 *db, /* The database connection */ |
9192 | const char *zSchema, /* Which DB to serialize. ex: "main", "temp", ... */ |
9193 | sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */ |
9194 | unsigned int mFlags /* Zero or more SQLITE_SERIALIZE_* flags */ |
9195 | ); |
9196 | |
9197 | /* |
9198 | ** CAPI3REF: Flags for sqlite3_serialize |
9199 | ** |
9200 | ** Zero or more of the following constants can be OR-ed together for |
9201 | ** the F argument to [sqlite3_serialize(D,S,P,F)]. |
9202 | ** |
9203 | ** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return |
9204 | ** a pointer to contiguous in-memory database that it is currently using, |
9205 | ** without making a copy of the database. If SQLite is not currently using |
9206 | ** a contiguous in-memory database, then this option causes |
9207 | ** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be |
9208 | ** using a contiguous in-memory database if it has been initialized by a |
9209 | ** prior call to [sqlite3_deserialize()]. |
9210 | */ |
9211 | #define SQLITE_SERIALIZE_NOCOPY 0x001 /* Do no memory allocations */ |
9212 | |
9213 | /* |
9214 | ** CAPI3REF: Deserialize a database |
9215 | ** |
9216 | ** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the |
9217 | ** [database connection] D to disconnect from database S and then |
9218 | ** reopen S as an in-memory database based on the serialization contained |
9219 | ** in P. The serialized database P is N bytes in size. M is the size of |
9220 | ** the buffer P, which might be larger than N. If M is larger than N, and |
9221 | ** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is |
9222 | ** permitted to add content to the in-memory database as long as the total |
9223 | ** size does not exceed M bytes. |
9224 | ** |
9225 | ** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will |
9226 | ** invoke sqlite3_free() on the serialization buffer when the database |
9227 | ** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then |
9228 | ** SQLite will try to increase the buffer size using sqlite3_realloc64() |
9229 | ** if writes on the database cause it to grow larger than M bytes. |
9230 | ** |
9231 | ** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the |
9232 | ** database is currently in a read transaction or is involved in a backup |
9233 | ** operation. |
9234 | ** |
9235 | ** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the |
9236 | ** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then |
9237 | ** [sqlite3_free()] is invoked on argument P prior to returning. |
9238 | ** |
9239 | ** This interface is only available if SQLite is compiled with the |
9240 | ** [SQLITE_ENABLE_DESERIALIZE] option. |
9241 | */ |
9242 | SQLITE_API int sqlite3_deserialize( |
9243 | sqlite3 *db, /* The database connection */ |
9244 | const char *zSchema, /* Which DB to reopen with the deserialization */ |
9245 | unsigned char *pData, /* The serialized database content */ |
9246 | sqlite3_int64 szDb, /* Number bytes in the deserialization */ |
9247 | sqlite3_int64 szBuf, /* Total size of buffer pData[] */ |
9248 | unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */ |
9249 | ); |
9250 | |
9251 | /* |
9252 | ** CAPI3REF: Flags for sqlite3_deserialize() |
9253 | ** |
9254 | ** The following are allowed values for 6th argument (the F argument) to |
9255 | ** the [sqlite3_deserialize(D,S,P,N,M,F)] interface. |
9256 | ** |
9257 | ** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization |
9258 | ** in the P argument is held in memory obtained from [sqlite3_malloc64()] |
9259 | ** and that SQLite should take ownership of this memory and automatically |
9260 | ** free it when it has finished using it. Without this flag, the caller |
9261 | ** is responsible for freeing any dynamically allocated memory. |
9262 | ** |
9263 | ** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to |
9264 | ** grow the size of the database using calls to [sqlite3_realloc64()]. This |
9265 | ** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used. |
9266 | ** Without this flag, the deserialized database cannot increase in size beyond |
9267 | ** the number of bytes specified by the M parameter. |
9268 | ** |
9269 | ** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database |
9270 | ** should be treated as read-only. |
9271 | */ |
9272 | #define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */ |
9273 | #define SQLITE_DESERIALIZE_RESIZEABLE 2 /* Resize using sqlite3_realloc64() */ |
9274 | #define SQLITE_DESERIALIZE_READONLY 4 /* Database is read-only */ |
9275 | |
9276 | /* |
9277 | ** Undo the hack that converts floating point types to integer for |
9278 | ** builds on processors without floating point support. |
9279 | */ |
9280 | #ifdef SQLITE_OMIT_FLOATING_POINT |
9281 | # undef double |
9282 | #endif |
9283 | |
9284 | #ifdef __cplusplus |
9285 | } /* End of the 'extern "C"' block */ |
9286 | #endif |
9287 | #endif /* SQLITE3_H */ |
9288 | |
9289 | /******** Begin file sqlite3rtree.h *********/ |
9290 | /* |
9291 | ** 2010 August 30 |
9292 | ** |
9293 | ** The author disclaims copyright to this source code. In place of |
9294 | ** a legal notice, here is a blessing: |
9295 | ** |
9296 | ** May you do good and not evil. |
9297 | ** May you find forgiveness for yourself and forgive others. |
9298 | ** May you share freely, never taking more than you give. |
9299 | ** |
9300 | ************************************************************************* |
9301 | */ |
9302 | |
9303 | #ifndef _SQLITE3RTREE_H_ |
9304 | #define _SQLITE3RTREE_H_ |
9305 | |
9306 | |
9307 | #ifdef __cplusplus |
9308 | extern "C" { |
9309 | #endif |
9310 | |
9311 | typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry; |
9312 | typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info; |
9313 | |
9314 | /* The double-precision datatype used by RTree depends on the |
9315 | ** SQLITE_RTREE_INT_ONLY compile-time option. |
9316 | */ |
9317 | #ifdef SQLITE_RTREE_INT_ONLY |
9318 | typedef sqlite3_int64 sqlite3_rtree_dbl; |
9319 | #else |
9320 | typedef double sqlite3_rtree_dbl; |
9321 | #endif |
9322 | |
9323 | /* |
9324 | ** Register a geometry callback named zGeom that can be used as part of an |
9325 | ** R-Tree geometry query as follows: |
9326 | ** |
9327 | ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...) |
9328 | */ |
9329 | SQLITE_API int sqlite3_rtree_geometry_callback( |
9330 | sqlite3 *db, |
9331 | const char *zGeom, |
9332 | int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*), |
9333 | void *pContext |
9334 | ); |
9335 | |
9336 | |
9337 | /* |
9338 | ** A pointer to a structure of the following type is passed as the first |
9339 | ** argument to callbacks registered using rtree_geometry_callback(). |
9340 | */ |
9341 | struct sqlite3_rtree_geometry { |
9342 | void *pContext; /* Copy of pContext passed to s_r_g_c() */ |
9343 | int nParam; /* Size of array aParam[] */ |
9344 | sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */ |
9345 | void *pUser; /* Callback implementation user data */ |
9346 | void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */ |
9347 | }; |
9348 | |
9349 | /* |
9350 | ** Register a 2nd-generation geometry callback named zScore that can be |
9351 | ** used as part of an R-Tree geometry query as follows: |
9352 | ** |
9353 | ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...) |
9354 | */ |
9355 | SQLITE_API int sqlite3_rtree_query_callback( |
9356 | sqlite3 *db, |
9357 | const char *zQueryFunc, |
9358 | int (*xQueryFunc)(sqlite3_rtree_query_info*), |
9359 | void *pContext, |
9360 | void (*xDestructor)(void*) |
9361 | ); |
9362 | |
9363 | |
9364 | /* |
9365 | ** A pointer to a structure of the following type is passed as the |
9366 | ** argument to scored geometry callback registered using |
9367 | ** sqlite3_rtree_query_callback(). |
9368 | ** |
9369 | ** Note that the first 5 fields of this structure are identical to |
9370 | ** sqlite3_rtree_geometry. This structure is a subclass of |
9371 | ** sqlite3_rtree_geometry. |
9372 | */ |
9373 | struct sqlite3_rtree_query_info { |
9374 | void *pContext; /* pContext from when function registered */ |
9375 | int nParam; /* Number of function parameters */ |
9376 | sqlite3_rtree_dbl *aParam; /* value of function parameters */ |
9377 | void *pUser; /* callback can use this, if desired */ |
9378 | void (*xDelUser)(void*); /* function to free pUser */ |
9379 | sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */ |
9380 | unsigned int *anQueue; /* Number of pending entries in the queue */ |
9381 | int nCoord; /* Number of coordinates */ |
9382 | int iLevel; /* Level of current node or entry */ |
9383 | int mxLevel; /* The largest iLevel value in the tree */ |
9384 | sqlite3_int64 iRowid; /* Rowid for current entry */ |
9385 | sqlite3_rtree_dbl rParentScore; /* Score of parent node */ |
9386 | int eParentWithin; /* Visibility of parent node */ |
9387 | int eWithin; /* OUT: Visiblity */ |
9388 | sqlite3_rtree_dbl rScore; /* OUT: Write the score here */ |
9389 | /* The following fields are only available in 3.8.11 and later */ |
9390 | sqlite3_value **apSqlParam; /* Original SQL values of parameters */ |
9391 | }; |
9392 | |
9393 | /* |
9394 | ** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin. |
9395 | */ |
9396 | #define NOT_WITHIN 0 /* Object completely outside of query region */ |
9397 | #define PARTLY_WITHIN 1 /* Object partially overlaps query region */ |
9398 | #define FULLY_WITHIN 2 /* Object fully contained within query region */ |
9399 | |
9400 | |
9401 | #ifdef __cplusplus |
9402 | } /* end of the 'extern "C"' block */ |
9403 | #endif |
9404 | |
9405 | #endif /* ifndef _SQLITE3RTREE_H_ */ |
9406 | |
9407 | /******** End of sqlite3rtree.h *********/ |
9408 | /******** Begin file sqlite3session.h *********/ |
9409 | |
9410 | #if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) |
9411 | #define __SQLITESESSION_H_ 1 |
9412 | |
9413 | /* |
9414 | ** Make sure we can call this stuff from C++. |
9415 | */ |
9416 | #ifdef __cplusplus |
9417 | extern "C" { |
9418 | #endif |
9419 | |
9420 | |
9421 | /* |
9422 | ** CAPI3REF: Session Object Handle |
9423 | ** |
9424 | ** An instance of this object is a [session] that can be used to |
9425 | ** record changes to a database. |
9426 | */ |
9427 | typedef struct sqlite3_session sqlite3_session; |
9428 | |
9429 | /* |
9430 | ** CAPI3REF: Changeset Iterator Handle |
9431 | ** |
9432 | ** An instance of this object acts as a cursor for iterating |
9433 | ** over the elements of a [changeset] or [patchset]. |
9434 | */ |
9435 | typedef struct sqlite3_changeset_iter sqlite3_changeset_iter; |
9436 | |
9437 | /* |
9438 | ** CAPI3REF: Create A New Session Object |
9439 | ** CONSTRUCTOR: sqlite3_session |
9440 | ** |
9441 | ** Create a new session object attached to database handle db. If successful, |
9442 | ** a pointer to the new object is written to *ppSession and SQLITE_OK is |
9443 | ** returned. If an error occurs, *ppSession is set to NULL and an SQLite |
9444 | ** error code (e.g. SQLITE_NOMEM) is returned. |
9445 | ** |
9446 | ** It is possible to create multiple session objects attached to a single |
9447 | ** database handle. |
9448 | ** |
9449 | ** Session objects created using this function should be deleted using the |
9450 | ** [sqlite3session_delete()] function before the database handle that they |
9451 | ** are attached to is itself closed. If the database handle is closed before |
9452 | ** the session object is deleted, then the results of calling any session |
9453 | ** module function, including [sqlite3session_delete()] on the session object |
9454 | ** are undefined. |
9455 | ** |
9456 | ** Because the session module uses the [sqlite3_preupdate_hook()] API, it |
9457 | ** is not possible for an application to register a pre-update hook on a |
9458 | ** database handle that has one or more session objects attached. Nor is |
9459 | ** it possible to create a session object attached to a database handle for |
9460 | ** which a pre-update hook is already defined. The results of attempting |
9461 | ** either of these things are undefined. |
9462 | ** |
9463 | ** The session object will be used to create changesets for tables in |
9464 | ** database zDb, where zDb is either "main", or "temp", or the name of an |
9465 | ** attached database. It is not an error if database zDb is not attached |
9466 | ** to the database when the session object is created. |
9467 | */ |
9468 | SQLITE_API int sqlite3session_create( |
9469 | sqlite3 *db, /* Database handle */ |
9470 | const char *zDb, /* Name of db (e.g. "main") */ |
9471 | sqlite3_session **ppSession /* OUT: New session object */ |
9472 | ); |
9473 | |
9474 | /* |
9475 | ** CAPI3REF: Delete A Session Object |
9476 | ** DESTRUCTOR: sqlite3_session |
9477 | ** |
9478 | ** Delete a session object previously allocated using |
9479 | ** [sqlite3session_create()]. Once a session object has been deleted, the |
9480 | ** results of attempting to use pSession with any other session module |
9481 | ** function are undefined. |
9482 | ** |
9483 | ** Session objects must be deleted before the database handle to which they |
9484 | ** are attached is closed. Refer to the documentation for |
9485 | ** [sqlite3session_create()] for details. |
9486 | */ |
9487 | SQLITE_API void sqlite3session_delete(sqlite3_session *pSession); |
9488 | |
9489 | |
9490 | /* |
9491 | ** CAPI3REF: Enable Or Disable A Session Object |
9492 | ** METHOD: sqlite3_session |
9493 | ** |
9494 | ** Enable or disable the recording of changes by a session object. When |
9495 | ** enabled, a session object records changes made to the database. When |
9496 | ** disabled - it does not. A newly created session object is enabled. |
9497 | ** Refer to the documentation for [sqlite3session_changeset()] for further |
9498 | ** details regarding how enabling and disabling a session object affects |
9499 | ** the eventual changesets. |
9500 | ** |
9501 | ** Passing zero to this function disables the session. Passing a value |
9502 | ** greater than zero enables it. Passing a value less than zero is a |
9503 | ** no-op, and may be used to query the current state of the session. |
9504 | ** |
9505 | ** The return value indicates the final state of the session object: 0 if |
9506 | ** the session is disabled, or 1 if it is enabled. |
9507 | */ |
9508 | SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable); |
9509 | |
9510 | /* |
9511 | ** CAPI3REF: Set Or Clear the Indirect Change Flag |
9512 | ** METHOD: sqlite3_session |
9513 | ** |
9514 | ** Each change recorded by a session object is marked as either direct or |
9515 | ** indirect. A change is marked as indirect if either: |
9516 | ** |
9517 | ** <ul> |
9518 | ** <li> The session object "indirect" flag is set when the change is |
9519 | ** made, or |
9520 | ** <li> The change is made by an SQL trigger or foreign key action |
9521 | ** instead of directly as a result of a users SQL statement. |
9522 | ** </ul> |
9523 | ** |
9524 | ** If a single row is affected by more than one operation within a session, |
9525 | ** then the change is considered indirect if all operations meet the criteria |
9526 | ** for an indirect change above, or direct otherwise. |
9527 | ** |
9528 | ** This function is used to set, clear or query the session object indirect |
9529 | ** flag. If the second argument passed to this function is zero, then the |
9530 | ** indirect flag is cleared. If it is greater than zero, the indirect flag |
9531 | ** is set. Passing a value less than zero does not modify the current value |
9532 | ** of the indirect flag, and may be used to query the current state of the |
9533 | ** indirect flag for the specified session object. |
9534 | ** |
9535 | ** The return value indicates the final state of the indirect flag: 0 if |
9536 | ** it is clear, or 1 if it is set. |
9537 | */ |
9538 | SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect); |
9539 | |
9540 | /* |
9541 | ** CAPI3REF: Attach A Table To A Session Object |
9542 | ** METHOD: sqlite3_session |
9543 | ** |
9544 | ** If argument zTab is not NULL, then it is the name of a table to attach |
9545 | ** to the session object passed as the first argument. All subsequent changes |
9546 | ** made to the table while the session object is enabled will be recorded. See |
9547 | ** documentation for [sqlite3session_changeset()] for further details. |
9548 | ** |
9549 | ** Or, if argument zTab is NULL, then changes are recorded for all tables |
9550 | ** in the database. If additional tables are added to the database (by |
9551 | ** executing "CREATE TABLE" statements) after this call is made, changes for |
9552 | ** the new tables are also recorded. |
9553 | ** |
9554 | ** Changes can only be recorded for tables that have a PRIMARY KEY explicitly |
9555 | ** defined as part of their CREATE TABLE statement. It does not matter if the |
9556 | ** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY |
9557 | ** KEY may consist of a single column, or may be a composite key. |
9558 | ** |
9559 | ** It is not an error if the named table does not exist in the database. Nor |
9560 | ** is it an error if the named table does not have a PRIMARY KEY. However, |
9561 | ** no changes will be recorded in either of these scenarios. |
9562 | ** |
9563 | ** Changes are not recorded for individual rows that have NULL values stored |
9564 | ** in one or more of their PRIMARY KEY columns. |
9565 | ** |
9566 | ** SQLITE_OK is returned if the call completes without error. Or, if an error |
9567 | ** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned. |
9568 | ** |
9569 | ** <h3>Special sqlite_stat1 Handling</h3> |
9570 | ** |
9571 | ** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to |
9572 | ** some of the rules above. In SQLite, the schema of sqlite_stat1 is: |
9573 | ** <pre> |
9574 | ** CREATE TABLE sqlite_stat1(tbl,idx,stat) |
9575 | ** </pre> |
9576 | ** |
9577 | ** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are |
9578 | ** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes |
9579 | ** are recorded for rows for which (idx IS NULL) is true. However, for such |
9580 | ** rows a zero-length blob (SQL value X'') is stored in the changeset or |
9581 | ** patchset instead of a NULL value. This allows such changesets to be |
9582 | ** manipulated by legacy implementations of sqlite3changeset_invert(), |
9583 | ** concat() and similar. |
9584 | ** |
9585 | ** The sqlite3changeset_apply() function automatically converts the |
9586 | ** zero-length blob back to a NULL value when updating the sqlite_stat1 |
9587 | ** table. However, if the application calls sqlite3changeset_new(), |
9588 | ** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset |
9589 | ** iterator directly (including on a changeset iterator passed to a |
9590 | ** conflict-handler callback) then the X'' value is returned. The application |
9591 | ** must translate X'' to NULL itself if required. |
9592 | ** |
9593 | ** Legacy (older than 3.22.0) versions of the sessions module cannot capture |
9594 | ** changes made to the sqlite_stat1 table. Legacy versions of the |
9595 | ** sqlite3changeset_apply() function silently ignore any modifications to the |
9596 | ** sqlite_stat1 table that are part of a changeset or patchset. |
9597 | */ |
9598 | SQLITE_API int sqlite3session_attach( |
9599 | sqlite3_session *pSession, /* Session object */ |
9600 | const char *zTab /* Table name */ |
9601 | ); |
9602 | |
9603 | /* |
9604 | ** CAPI3REF: Set a table filter on a Session Object. |
9605 | ** METHOD: sqlite3_session |
9606 | ** |
9607 | ** The second argument (xFilter) is the "filter callback". For changes to rows |
9608 | ** in tables that are not attached to the Session object, the filter is called |
9609 | ** to determine whether changes to the table's rows should be tracked or not. |
9610 | ** If xFilter returns 0, changes is not tracked. Note that once a table is |
9611 | ** attached, xFilter will not be called again. |
9612 | */ |
9613 | SQLITE_API void sqlite3session_table_filter( |
9614 | sqlite3_session *pSession, /* Session object */ |
9615 | int(*xFilter)( |
9616 | void *pCtx, /* Copy of third arg to _filter_table() */ |
9617 | const char *zTab /* Table name */ |
9618 | ), |
9619 | void *pCtx /* First argument passed to xFilter */ |
9620 | ); |
9621 | |
9622 | /* |
9623 | ** CAPI3REF: Generate A Changeset From A Session Object |
9624 | ** METHOD: sqlite3_session |
9625 | ** |
9626 | ** Obtain a changeset containing changes to the tables attached to the |
9627 | ** session object passed as the first argument. If successful, |
9628 | ** set *ppChangeset to point to a buffer containing the changeset |
9629 | ** and *pnChangeset to the size of the changeset in bytes before returning |
9630 | ** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to |
9631 | ** zero and return an SQLite error code. |
9632 | ** |
9633 | ** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes, |
9634 | ** each representing a change to a single row of an attached table. An INSERT |
9635 | ** change contains the values of each field of a new database row. A DELETE |
9636 | ** contains the original values of each field of a deleted database row. An |
9637 | ** UPDATE change contains the original values of each field of an updated |
9638 | ** database row along with the updated values for each updated non-primary-key |
9639 | ** column. It is not possible for an UPDATE change to represent a change that |
9640 | ** modifies the values of primary key columns. If such a change is made, it |
9641 | ** is represented in a changeset as a DELETE followed by an INSERT. |
9642 | ** |
9643 | ** Changes are not recorded for rows that have NULL values stored in one or |
9644 | ** more of their PRIMARY KEY columns. If such a row is inserted or deleted, |
9645 | ** no corresponding change is present in the changesets returned by this |
9646 | ** function. If an existing row with one or more NULL values stored in |
9647 | ** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL, |
9648 | ** only an INSERT is appears in the changeset. Similarly, if an existing row |
9649 | ** with non-NULL PRIMARY KEY values is updated so that one or more of its |
9650 | ** PRIMARY KEY columns are set to NULL, the resulting changeset contains a |
9651 | ** DELETE change only. |
9652 | ** |
9653 | ** The contents of a changeset may be traversed using an iterator created |
9654 | ** using the [sqlite3changeset_start()] API. A changeset may be applied to |
9655 | ** a database with a compatible schema using the [sqlite3changeset_apply()] |
9656 | ** API. |
9657 | ** |
9658 | ** Within a changeset generated by this function, all changes related to a |
9659 | ** single table are grouped together. In other words, when iterating through |
9660 | ** a changeset or when applying a changeset to a database, all changes related |
9661 | ** to a single table are processed before moving on to the next table. Tables |
9662 | ** are sorted in the same order in which they were attached (or auto-attached) |
9663 | ** to the sqlite3_session object. The order in which the changes related to |
9664 | ** a single table are stored is undefined. |
9665 | ** |
9666 | ** Following a successful call to this function, it is the responsibility of |
9667 | ** the caller to eventually free the buffer that *ppChangeset points to using |
9668 | ** [sqlite3_free()]. |
9669 | ** |
9670 | ** <h3>Changeset Generation</h3> |
9671 | ** |
9672 | ** Once a table has been attached to a session object, the session object |
9673 | ** records the primary key values of all new rows inserted into the table. |
9674 | ** It also records the original primary key and other column values of any |
9675 | ** deleted or updated rows. For each unique primary key value, data is only |
9676 | ** recorded once - the first time a row with said primary key is inserted, |
9677 | ** updated or deleted in the lifetime of the session. |
9678 | ** |
9679 | ** There is one exception to the previous paragraph: when a row is inserted, |
9680 | ** updated or deleted, if one or more of its primary key columns contain a |
9681 | ** NULL value, no record of the change is made. |
9682 | ** |
9683 | ** The session object therefore accumulates two types of records - those |
9684 | ** that consist of primary key values only (created when the user inserts |
9685 | ** a new record) and those that consist of the primary key values and the |
9686 | ** original values of other table columns (created when the users deletes |
9687 | ** or updates a record). |
9688 | ** |
9689 | ** When this function is called, the requested changeset is created using |
9690 | ** both the accumulated records and the current contents of the database |
9691 | ** file. Specifically: |
9692 | ** |
9693 | ** <ul> |
9694 | ** <li> For each record generated by an insert, the database is queried |
9695 | ** for a row with a matching primary key. If one is found, an INSERT |
9696 | ** change is added to the changeset. If no such row is found, no change |
9697 | ** is added to the changeset. |
9698 | ** |
9699 | ** <li> For each record generated by an update or delete, the database is |
9700 | ** queried for a row with a matching primary key. If such a row is |
9701 | ** found and one or more of the non-primary key fields have been |
9702 | ** modified from their original values, an UPDATE change is added to |
9703 | ** the changeset. Or, if no such row is found in the table, a DELETE |
9704 | ** change is added to the changeset. If there is a row with a matching |
9705 | ** primary key in the database, but all fields contain their original |
9706 | ** values, no change is added to the changeset. |
9707 | ** </ul> |
9708 | ** |
9709 | ** This means, amongst other things, that if a row is inserted and then later |
9710 | ** deleted while a session object is active, neither the insert nor the delete |
9711 | ** will be present in the changeset. Or if a row is deleted and then later a |
9712 | ** row with the same primary key values inserted while a session object is |
9713 | ** active, the resulting changeset will contain an UPDATE change instead of |
9714 | ** a DELETE and an INSERT. |
9715 | ** |
9716 | ** When a session object is disabled (see the [sqlite3session_enable()] API), |
9717 | ** it does not accumulate records when rows are inserted, updated or deleted. |
9718 | ** This may appear to have some counter-intuitive effects if a single row |
9719 | ** is written to more than once during a session. For example, if a row |
9720 | ** is inserted while a session object is enabled, then later deleted while |
9721 | ** the same session object is disabled, no INSERT record will appear in the |
9722 | ** changeset, even though the delete took place while the session was disabled. |
9723 | ** Or, if one field of a row is updated while a session is disabled, and |
9724 | ** another field of the same row is updated while the session is enabled, the |
9725 | ** resulting changeset will contain an UPDATE change that updates both fields. |
9726 | */ |
9727 | SQLITE_API int sqlite3session_changeset( |
9728 | sqlite3_session *pSession, /* Session object */ |
9729 | int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */ |
9730 | void **ppChangeset /* OUT: Buffer containing changeset */ |
9731 | ); |
9732 | |
9733 | /* |
9734 | ** CAPI3REF: Load The Difference Between Tables Into A Session |
9735 | ** METHOD: sqlite3_session |
9736 | ** |
9737 | ** If it is not already attached to the session object passed as the first |
9738 | ** argument, this function attaches table zTbl in the same manner as the |
9739 | ** [sqlite3session_attach()] function. If zTbl does not exist, or if it |
9740 | ** does not have a primary key, this function is a no-op (but does not return |
9741 | ** an error). |
9742 | ** |
9743 | ** Argument zFromDb must be the name of a database ("main", "temp" etc.) |
9744 | ** attached to the same database handle as the session object that contains |
9745 | ** a table compatible with the table attached to the session by this function. |
9746 | ** A table is considered compatible if it: |
9747 | ** |
9748 | ** <ul> |
9749 | ** <li> Has the same name, |
9750 | ** <li> Has the same set of columns declared in the same order, and |
9751 | ** <li> Has the same PRIMARY KEY definition. |
9752 | ** </ul> |
9753 | ** |
9754 | ** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables |
9755 | ** are compatible but do not have any PRIMARY KEY columns, it is not an error |
9756 | ** but no changes are added to the session object. As with other session |
9757 | ** APIs, tables without PRIMARY KEYs are simply ignored. |
9758 | ** |
9759 | ** This function adds a set of changes to the session object that could be |
9760 | ** used to update the table in database zFrom (call this the "from-table") |
9761 | ** so that its content is the same as the table attached to the session |
9762 | ** object (call this the "to-table"). Specifically: |
9763 | ** |
9764 | ** <ul> |
9765 | ** <li> For each row (primary key) that exists in the to-table but not in |
9766 | ** the from-table, an INSERT record is added to the session object. |
9767 | ** |
9768 | ** <li> For each row (primary key) that exists in the to-table but not in |
9769 | ** the from-table, a DELETE record is added to the session object. |
9770 | ** |
9771 | ** <li> For each row (primary key) that exists in both tables, but features |
9772 | ** different non-PK values in each, an UPDATE record is added to the |
9773 | ** session. |
9774 | ** </ul> |
9775 | ** |
9776 | ** To clarify, if this function is called and then a changeset constructed |
9777 | ** using [sqlite3session_changeset()], then after applying that changeset to |
9778 | ** database zFrom the contents of the two compatible tables would be |
9779 | ** identical. |
9780 | ** |
9781 | ** It an error if database zFrom does not exist or does not contain the |
9782 | ** required compatible table. |
9783 | ** |
9784 | ** If the operation successful, SQLITE_OK is returned. Otherwise, an SQLite |
9785 | ** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg |
9786 | ** may be set to point to a buffer containing an English language error |
9787 | ** message. It is the responsibility of the caller to free this buffer using |
9788 | ** sqlite3_free(). |
9789 | */ |
9790 | SQLITE_API int sqlite3session_diff( |
9791 | sqlite3_session *pSession, |
9792 | const char *zFromDb, |
9793 | const char *zTbl, |
9794 | char **pzErrMsg |
9795 | ); |
9796 | |
9797 | |
9798 | /* |
9799 | ** CAPI3REF: Generate A Patchset From A Session Object |
9800 | ** METHOD: sqlite3_session |
9801 | ** |
9802 | ** The differences between a patchset and a changeset are that: |
9803 | ** |
9804 | ** <ul> |
9805 | ** <li> DELETE records consist of the primary key fields only. The |
9806 | ** original values of other fields are omitted. |
9807 | ** <li> The original values of any modified fields are omitted from |
9808 | ** UPDATE records. |
9809 | ** </ul> |
9810 | ** |
9811 | ** A patchset blob may be used with up to date versions of all |
9812 | ** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(), |
9813 | ** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly, |
9814 | ** attempting to use a patchset blob with old versions of the |
9815 | ** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error. |
9816 | ** |
9817 | ** Because the non-primary key "old.*" fields are omitted, no |
9818 | ** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset |
9819 | ** is passed to the sqlite3changeset_apply() API. Other conflict types work |
9820 | ** in the same way as for changesets. |
9821 | ** |
9822 | ** Changes within a patchset are ordered in the same way as for changesets |
9823 | ** generated by the sqlite3session_changeset() function (i.e. all changes for |
9824 | ** a single table are grouped together, tables appear in the order in which |
9825 | ** they were attached to the session object). |
9826 | */ |
9827 | SQLITE_API int sqlite3session_patchset( |
9828 | sqlite3_session *pSession, /* Session object */ |
9829 | int *pnPatchset, /* OUT: Size of buffer at *ppPatchset */ |
9830 | void **ppPatchset /* OUT: Buffer containing patchset */ |
9831 | ); |
9832 | |
9833 | /* |
9834 | ** CAPI3REF: Test if a changeset has recorded any changes. |
9835 | ** |
9836 | ** Return non-zero if no changes to attached tables have been recorded by |
9837 | ** the session object passed as the first argument. Otherwise, if one or |
9838 | ** more changes have been recorded, return zero. |
9839 | ** |
9840 | ** Even if this function returns zero, it is possible that calling |
9841 | ** [sqlite3session_changeset()] on the session handle may still return a |
9842 | ** changeset that contains no changes. This can happen when a row in |
9843 | ** an attached table is modified and then later on the original values |
9844 | ** are restored. However, if this function returns non-zero, then it is |
9845 | ** guaranteed that a call to sqlite3session_changeset() will return a |
9846 | ** changeset containing zero changes. |
9847 | */ |
9848 | SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession); |
9849 | |
9850 | /* |
9851 | ** CAPI3REF: Create An Iterator To Traverse A Changeset |
9852 | ** CONSTRUCTOR: sqlite3_changeset_iter |
9853 | ** |
9854 | ** Create an iterator used to iterate through the contents of a changeset. |
9855 | ** If successful, *pp is set to point to the iterator handle and SQLITE_OK |
9856 | ** is returned. Otherwise, if an error occurs, *pp is set to zero and an |
9857 | ** SQLite error code is returned. |
9858 | ** |
9859 | ** The following functions can be used to advance and query a changeset |
9860 | ** iterator created by this function: |
9861 | ** |
9862 | ** <ul> |
9863 | ** <li> [sqlite3changeset_next()] |
9864 | ** <li> [sqlite3changeset_op()] |
9865 | ** <li> [sqlite3changeset_new()] |
9866 | ** <li> [sqlite3changeset_old()] |
9867 | ** </ul> |
9868 | ** |
9869 | ** It is the responsibility of the caller to eventually destroy the iterator |
9870 | ** by passing it to [sqlite3changeset_finalize()]. The buffer containing the |
9871 | ** changeset (pChangeset) must remain valid until after the iterator is |
9872 | ** destroyed. |
9873 | ** |
9874 | ** Assuming the changeset blob was created by one of the |
9875 | ** [sqlite3session_changeset()], [sqlite3changeset_concat()] or |
9876 | ** [sqlite3changeset_invert()] functions, all changes within the changeset |
9877 | ** that apply to a single table are grouped together. This means that when |
9878 | ** an application iterates through a changeset using an iterator created by |
9879 | ** this function, all changes that relate to a single table are visited |
9880 | ** consecutively. There is no chance that the iterator will visit a change |
9881 | ** the applies to table X, then one for table Y, and then later on visit |
9882 | ** another change for table X. |
9883 | */ |
9884 | SQLITE_API int sqlite3changeset_start( |
9885 | sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ |
9886 | int nChangeset, /* Size of changeset blob in bytes */ |
9887 | void *pChangeset /* Pointer to blob containing changeset */ |
9888 | ); |
9889 | |
9890 | |
9891 | /* |
9892 | ** CAPI3REF: Advance A Changeset Iterator |
9893 | ** METHOD: sqlite3_changeset_iter |
9894 | ** |
9895 | ** This function may only be used with iterators created by function |
9896 | ** [sqlite3changeset_start()]. If it is called on an iterator passed to |
9897 | ** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE |
9898 | ** is returned and the call has no effect. |
9899 | ** |
9900 | ** Immediately after an iterator is created by sqlite3changeset_start(), it |
9901 | ** does not point to any change in the changeset. Assuming the changeset |
9902 | ** is not empty, the first call to this function advances the iterator to |
9903 | ** point to the first change in the changeset. Each subsequent call advances |
9904 | ** the iterator to point to the next change in the changeset (if any). If |
9905 | ** no error occurs and the iterator points to a valid change after a call |
9906 | ** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned. |
9907 | ** Otherwise, if all changes in the changeset have already been visited, |
9908 | ** SQLITE_DONE is returned. |
9909 | ** |
9910 | ** If an error occurs, an SQLite error code is returned. Possible error |
9911 | ** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or |
9912 | ** SQLITE_NOMEM. |
9913 | */ |
9914 | SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter); |
9915 | |
9916 | /* |
9917 | ** CAPI3REF: Obtain The Current Operation From A Changeset Iterator |
9918 | ** METHOD: sqlite3_changeset_iter |
9919 | ** |
9920 | ** The pIter argument passed to this function may either be an iterator |
9921 | ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator |
9922 | ** created by [sqlite3changeset_start()]. In the latter case, the most recent |
9923 | ** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this |
9924 | ** is not the case, this function returns [SQLITE_MISUSE]. |
9925 | ** |
9926 | ** If argument pzTab is not NULL, then *pzTab is set to point to a |
9927 | ** nul-terminated utf-8 encoded string containing the name of the table |
9928 | ** affected by the current change. The buffer remains valid until either |
9929 | ** sqlite3changeset_next() is called on the iterator or until the |
9930 | ** conflict-handler function returns. If pnCol is not NULL, then *pnCol is |
9931 | ** set to the number of columns in the table affected by the change. If |
9932 | ** pbIncorrect is not NULL, then *pbIndirect is set to true (1) if the change |
9933 | ** is an indirect change, or false (0) otherwise. See the documentation for |
9934 | ** [sqlite3session_indirect()] for a description of direct and indirect |
9935 | ** changes. Finally, if pOp is not NULL, then *pOp is set to one of |
9936 | ** [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], depending on the |
9937 | ** type of change that the iterator currently points to. |
9938 | ** |
9939 | ** If no error occurs, SQLITE_OK is returned. If an error does occur, an |
9940 | ** SQLite error code is returned. The values of the output variables may not |
9941 | ** be trusted in this case. |
9942 | */ |
9943 | SQLITE_API int sqlite3changeset_op( |
9944 | sqlite3_changeset_iter *pIter, /* Iterator object */ |
9945 | const char **pzTab, /* OUT: Pointer to table name */ |
9946 | int *pnCol, /* OUT: Number of columns in table */ |
9947 | int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */ |
9948 | int *pbIndirect /* OUT: True for an 'indirect' change */ |
9949 | ); |
9950 | |
9951 | /* |
9952 | ** CAPI3REF: Obtain The Primary Key Definition Of A Table |
9953 | ** METHOD: sqlite3_changeset_iter |
9954 | ** |
9955 | ** For each modified table, a changeset includes the following: |
9956 | ** |
9957 | ** <ul> |
9958 | ** <li> The number of columns in the table, and |
9959 | ** <li> Which of those columns make up the tables PRIMARY KEY. |
9960 | ** </ul> |
9961 | ** |
9962 | ** This function is used to find which columns comprise the PRIMARY KEY of |
9963 | ** the table modified by the change that iterator pIter currently points to. |
9964 | ** If successful, *pabPK is set to point to an array of nCol entries, where |
9965 | ** nCol is the number of columns in the table. Elements of *pabPK are set to |
9966 | ** 0x01 if the corresponding column is part of the tables primary key, or |
9967 | ** 0x00 if it is not. |
9968 | ** |
9969 | ** If argument pnCol is not NULL, then *pnCol is set to the number of columns |
9970 | ** in the table. |
9971 | ** |
9972 | ** If this function is called when the iterator does not point to a valid |
9973 | ** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise, |
9974 | ** SQLITE_OK is returned and the output variables populated as described |
9975 | ** above. |
9976 | */ |
9977 | SQLITE_API int sqlite3changeset_pk( |
9978 | sqlite3_changeset_iter *pIter, /* Iterator object */ |
9979 | unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */ |
9980 | int *pnCol /* OUT: Number of entries in output array */ |
9981 | ); |
9982 | |
9983 | /* |
9984 | ** CAPI3REF: Obtain old.* Values From A Changeset Iterator |
9985 | ** METHOD: sqlite3_changeset_iter |
9986 | ** |
9987 | ** The pIter argument passed to this function may either be an iterator |
9988 | ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator |
9989 | ** created by [sqlite3changeset_start()]. In the latter case, the most recent |
9990 | ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. |
9991 | ** Furthermore, it may only be called if the type of change that the iterator |
9992 | ** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise, |
9993 | ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. |
9994 | ** |
9995 | ** Argument iVal must be greater than or equal to 0, and less than the number |
9996 | ** of columns in the table affected by the current change. Otherwise, |
9997 | ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. |
9998 | ** |
9999 | ** If successful, this function sets *ppValue to point to a protected |
10000 | ** sqlite3_value object containing the iVal'th value from the vector of |
10001 | ** original row values stored as part of the UPDATE or DELETE change and |
10002 | ** returns SQLITE_OK. The name of the function comes from the fact that this |
10003 | ** is similar to the "old.*" columns available to update or delete triggers. |
10004 | ** |
10005 | ** If some other error occurs (e.g. an OOM condition), an SQLite error code |
10006 | ** is returned and *ppValue is set to NULL. |
10007 | */ |
10008 | SQLITE_API int sqlite3changeset_old( |
10009 | sqlite3_changeset_iter *pIter, /* Changeset iterator */ |
10010 | int iVal, /* Column number */ |
10011 | sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */ |
10012 | ); |
10013 | |
10014 | /* |
10015 | ** CAPI3REF: Obtain new.* Values From A Changeset Iterator |
10016 | ** METHOD: sqlite3_changeset_iter |
10017 | ** |
10018 | ** The pIter argument passed to this function may either be an iterator |
10019 | ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator |
10020 | ** created by [sqlite3changeset_start()]. In the latter case, the most recent |
10021 | ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. |
10022 | ** Furthermore, it may only be called if the type of change that the iterator |
10023 | ** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise, |
10024 | ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. |
10025 | ** |
10026 | ** Argument iVal must be greater than or equal to 0, and less than the number |
10027 | ** of columns in the table affected by the current change. Otherwise, |
10028 | ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. |
10029 | ** |
10030 | ** If successful, this function sets *ppValue to point to a protected |
10031 | ** sqlite3_value object containing the iVal'th value from the vector of |
10032 | ** new row values stored as part of the UPDATE or INSERT change and |
10033 | ** returns SQLITE_OK. If the change is an UPDATE and does not include |
10034 | ** a new value for the requested column, *ppValue is set to NULL and |
10035 | ** SQLITE_OK returned. The name of the function comes from the fact that |
10036 | ** this is similar to the "new.*" columns available to update or delete |
10037 | ** triggers. |
10038 | ** |
10039 | ** If some other error occurs (e.g. an OOM condition), an SQLite error code |
10040 | ** is returned and *ppValue is set to NULL. |
10041 | */ |
10042 | SQLITE_API int sqlite3changeset_new( |
10043 | sqlite3_changeset_iter *pIter, /* Changeset iterator */ |
10044 | int iVal, /* Column number */ |
10045 | sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */ |
10046 | ); |
10047 | |
10048 | /* |
10049 | ** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator |
10050 | ** METHOD: sqlite3_changeset_iter |
10051 | ** |
10052 | ** This function should only be used with iterator objects passed to a |
10053 | ** conflict-handler callback by [sqlite3changeset_apply()] with either |
10054 | ** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function |
10055 | ** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue |
10056 | ** is set to NULL. |
10057 | ** |
10058 | ** Argument iVal must be greater than or equal to 0, and less than the number |
10059 | ** of columns in the table affected by the current change. Otherwise, |
10060 | ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. |
10061 | ** |
10062 | ** If successful, this function sets *ppValue to point to a protected |
10063 | ** sqlite3_value object containing the iVal'th value from the |
10064 | ** "conflicting row" associated with the current conflict-handler callback |
10065 | ** and returns SQLITE_OK. |
10066 | ** |
10067 | ** If some other error occurs (e.g. an OOM condition), an SQLite error code |
10068 | ** is returned and *ppValue is set to NULL. |
10069 | */ |
10070 | SQLITE_API int sqlite3changeset_conflict( |
10071 | sqlite3_changeset_iter *pIter, /* Changeset iterator */ |
10072 | int iVal, /* Column number */ |
10073 | sqlite3_value **ppValue /* OUT: Value from conflicting row */ |
10074 | ); |
10075 | |
10076 | /* |
10077 | ** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations |
10078 | ** METHOD: sqlite3_changeset_iter |
10079 | ** |
10080 | ** This function may only be called with an iterator passed to an |
10081 | ** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case |
10082 | ** it sets the output variable to the total number of known foreign key |
10083 | ** violations in the destination database and returns SQLITE_OK. |
10084 | ** |
10085 | ** In all other cases this function returns SQLITE_MISUSE. |
10086 | */ |
10087 | SQLITE_API int sqlite3changeset_fk_conflicts( |
10088 | sqlite3_changeset_iter *pIter, /* Changeset iterator */ |
10089 | int *pnOut /* OUT: Number of FK violations */ |
10090 | ); |
10091 | |
10092 | |
10093 | /* |
10094 | ** CAPI3REF: Finalize A Changeset Iterator |
10095 | ** METHOD: sqlite3_changeset_iter |
10096 | ** |
10097 | ** This function is used to finalize an iterator allocated with |
10098 | ** [sqlite3changeset_start()]. |
10099 | ** |
10100 | ** This function should only be called on iterators created using the |
10101 | ** [sqlite3changeset_start()] function. If an application calls this |
10102 | ** function with an iterator passed to a conflict-handler by |
10103 | ** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the |
10104 | ** call has no effect. |
10105 | ** |
10106 | ** If an error was encountered within a call to an sqlite3changeset_xxx() |
10107 | ** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an |
10108 | ** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding |
10109 | ** to that error is returned by this function. Otherwise, SQLITE_OK is |
10110 | ** returned. This is to allow the following pattern (pseudo-code): |
10111 | ** |
10112 | ** <pre> |
10113 | ** sqlite3changeset_start(); |
10114 | ** while( SQLITE_ROW==sqlite3changeset_next() ){ |
10115 | ** // Do something with change. |
10116 | ** } |
10117 | ** rc = sqlite3changeset_finalize(); |
10118 | ** if( rc!=SQLITE_OK ){ |
10119 | ** // An error has occurred |
10120 | ** } |
10121 | ** </pre> |
10122 | */ |
10123 | SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter); |
10124 | |
10125 | /* |
10126 | ** CAPI3REF: Invert A Changeset |
10127 | ** |
10128 | ** This function is used to "invert" a changeset object. Applying an inverted |
10129 | ** changeset to a database reverses the effects of applying the uninverted |
10130 | ** changeset. Specifically: |
10131 | ** |
10132 | ** <ul> |
10133 | ** <li> Each DELETE change is changed to an INSERT, and |
10134 | ** <li> Each INSERT change is changed to a DELETE, and |
10135 | ** <li> For each UPDATE change, the old.* and new.* values are exchanged. |
10136 | ** </ul> |
10137 | ** |
10138 | ** This function does not change the order in which changes appear within |
10139 | ** the changeset. It merely reverses the sense of each individual change. |
10140 | ** |
10141 | ** If successful, a pointer to a buffer containing the inverted changeset |
10142 | ** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and |
10143 | ** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are |
10144 | ** zeroed and an SQLite error code returned. |
10145 | ** |
10146 | ** It is the responsibility of the caller to eventually call sqlite3_free() |
10147 | ** on the *ppOut pointer to free the buffer allocation following a successful |
10148 | ** call to this function. |
10149 | ** |
10150 | ** WARNING/TODO: This function currently assumes that the input is a valid |
10151 | ** changeset. If it is not, the results are undefined. |
10152 | */ |
10153 | SQLITE_API int sqlite3changeset_invert( |
10154 | int nIn, const void *pIn, /* Input changeset */ |
10155 | int *pnOut, void **ppOut /* OUT: Inverse of input */ |
10156 | ); |
10157 | |
10158 | /* |
10159 | ** CAPI3REF: Concatenate Two Changeset Objects |
10160 | ** |
10161 | ** This function is used to concatenate two changesets, A and B, into a |
10162 | ** single changeset. The result is a changeset equivalent to applying |
10163 | ** changeset A followed by changeset B. |
10164 | ** |
10165 | ** This function combines the two input changesets using an |
10166 | ** sqlite3_changegroup object. Calling it produces similar results as the |
10167 | ** following code fragment: |
10168 | ** |
10169 | ** <pre> |
10170 | ** sqlite3_changegroup *pGrp; |
10171 | ** rc = sqlite3_changegroup_new(&pGrp); |
10172 | ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA); |
10173 | ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB); |
10174 | ** if( rc==SQLITE_OK ){ |
10175 | ** rc = sqlite3changegroup_output(pGrp, pnOut, ppOut); |
10176 | ** }else{ |
10177 | ** *ppOut = 0; |
10178 | ** *pnOut = 0; |
10179 | ** } |
10180 | ** </pre> |
10181 | ** |
10182 | ** Refer to the sqlite3_changegroup documentation below for details. |
10183 | */ |
10184 | SQLITE_API int sqlite3changeset_concat( |
10185 | int nA, /* Number of bytes in buffer pA */ |
10186 | void *pA, /* Pointer to buffer containing changeset A */ |
10187 | int nB, /* Number of bytes in buffer pB */ |
10188 | void *pB, /* Pointer to buffer containing changeset B */ |
10189 | int *pnOut, /* OUT: Number of bytes in output changeset */ |
10190 | void **ppOut /* OUT: Buffer containing output changeset */ |
10191 | ); |
10192 | |
10193 | |
10194 | /* |
10195 | ** CAPI3REF: Changegroup Handle |
10196 | ** |
10197 | ** A changegroup is an object used to combine two or more |
10198 | ** [changesets] or [patchsets] |
10199 | */ |
10200 | typedef struct sqlite3_changegroup sqlite3_changegroup; |
10201 | |
10202 | /* |
10203 | ** CAPI3REF: Create A New Changegroup Object |
10204 | ** CONSTRUCTOR: sqlite3_changegroup |
10205 | ** |
10206 | ** An sqlite3_changegroup object is used to combine two or more changesets |
10207 | ** (or patchsets) into a single changeset (or patchset). A single changegroup |
10208 | ** object may combine changesets or patchsets, but not both. The output is |
10209 | ** always in the same format as the input. |
10210 | ** |
10211 | ** If successful, this function returns SQLITE_OK and populates (*pp) with |
10212 | ** a pointer to a new sqlite3_changegroup object before returning. The caller |
10213 | ** should eventually free the returned object using a call to |
10214 | ** sqlite3changegroup_delete(). If an error occurs, an SQLite error code |
10215 | ** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL. |
10216 | ** |
10217 | ** The usual usage pattern for an sqlite3_changegroup object is as follows: |
10218 | ** |
10219 | ** <ul> |
10220 | ** <li> It is created using a call to sqlite3changegroup_new(). |
10221 | ** |
10222 | ** <li> Zero or more changesets (or patchsets) are added to the object |
10223 | ** by calling sqlite3changegroup_add(). |
10224 | ** |
10225 | ** <li> The result of combining all input changesets together is obtained |
10226 | ** by the application via a call to sqlite3changegroup_output(). |
10227 | ** |
10228 | ** <li> The object is deleted using a call to sqlite3changegroup_delete(). |
10229 | ** </ul> |
10230 | ** |
10231 | ** Any number of calls to add() and output() may be made between the calls to |
10232 | ** new() and delete(), and in any order. |
10233 | ** |
10234 | ** As well as the regular sqlite3changegroup_add() and |
10235 | ** sqlite3changegroup_output() functions, also available are the streaming |
10236 | ** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm(). |
10237 | */ |
10238 | SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp); |
10239 | |
10240 | /* |
10241 | ** CAPI3REF: Add A Changeset To A Changegroup |
10242 | ** METHOD: sqlite3_changegroup |
10243 | ** |
10244 | ** Add all changes within the changeset (or patchset) in buffer pData (size |
10245 | ** nData bytes) to the changegroup. |
10246 | ** |
10247 | ** If the buffer contains a patchset, then all prior calls to this function |
10248 | ** on the same changegroup object must also have specified patchsets. Or, if |
10249 | ** the buffer contains a changeset, so must have the earlier calls to this |
10250 | ** function. Otherwise, SQLITE_ERROR is returned and no changes are added |
10251 | ** to the changegroup. |
10252 | ** |
10253 | ** Rows within the changeset and changegroup are identified by the values in |
10254 | ** their PRIMARY KEY columns. A change in the changeset is considered to |
10255 | ** apply to the same row as a change already present in the changegroup if |
10256 | ** the two rows have the same primary key. |
10257 | ** |
10258 | ** Changes to rows that do not already appear in the changegroup are |
10259 | ** simply copied into it. Or, if both the new changeset and the changegroup |
10260 | ** contain changes that apply to a single row, the final contents of the |
10261 | ** changegroup depends on the type of each change, as follows: |
10262 | ** |
10263 | ** <table border=1 style="margin-left:8ex;margin-right:8ex"> |
10264 | ** <tr><th style="white-space:pre">Existing Change </th> |
10265 | ** <th style="white-space:pre">New Change </th> |
10266 | ** <th>Output Change |
10267 | ** <tr><td>INSERT <td>INSERT <td> |
10268 | ** The new change is ignored. This case does not occur if the new |
10269 | ** changeset was recorded immediately after the changesets already |
10270 | ** added to the changegroup. |
10271 | ** <tr><td>INSERT <td>UPDATE <td> |
10272 | ** The INSERT change remains in the changegroup. The values in the |
10273 | ** INSERT change are modified as if the row was inserted by the |
10274 | ** existing change and then updated according to the new change. |
10275 | ** <tr><td>INSERT <td>DELETE <td> |
10276 | ** The existing INSERT is removed from the changegroup. The DELETE is |
10277 | ** not added. |
10278 | ** <tr><td>UPDATE <td>INSERT <td> |
10279 | ** The new change is ignored. This case does not occur if the new |
10280 | ** changeset was recorded immediately after the changesets already |
10281 | ** added to the changegroup. |
10282 | ** <tr><td>UPDATE <td>UPDATE <td> |
10283 | ** The existing UPDATE remains within the changegroup. It is amended |
10284 | ** so that the accompanying values are as if the row was updated once |
10285 | ** by the existing change and then again by the new change. |
10286 | ** <tr><td>UPDATE <td>DELETE <td> |
10287 | ** The existing UPDATE is replaced by the new DELETE within the |
10288 | ** changegroup. |
10289 | ** <tr><td>DELETE <td>INSERT <td> |
10290 | ** If one or more of the column values in the row inserted by the |
10291 | ** new change differ from those in the row deleted by the existing |
10292 | ** change, the existing DELETE is replaced by an UPDATE within the |
10293 | ** changegroup. Otherwise, if the inserted row is exactly the same |
10294 | ** as the deleted row, the existing DELETE is simply discarded. |
10295 | ** <tr><td>DELETE <td>UPDATE <td> |
10296 | ** The new change is ignored. This case does not occur if the new |
10297 | ** changeset was recorded immediately after the changesets already |
10298 | ** added to the changegroup. |
10299 | ** <tr><td>DELETE <td>DELETE <td> |
10300 | ** The new change is ignored. This case does not occur if the new |
10301 | ** changeset was recorded immediately after the changesets already |
10302 | ** added to the changegroup. |
10303 | ** </table> |
10304 | ** |
10305 | ** If the new changeset contains changes to a table that is already present |
10306 | ** in the changegroup, then the number of columns and the position of the |
10307 | ** primary key columns for the table must be consistent. If this is not the |
10308 | ** case, this function fails with SQLITE_SCHEMA. If the input changeset |
10309 | ** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is |
10310 | ** returned. Or, if an out-of-memory condition occurs during processing, this |
10311 | ** function returns SQLITE_NOMEM. In all cases, if an error occurs the |
10312 | ** final contents of the changegroup is undefined. |
10313 | ** |
10314 | ** If no error occurs, SQLITE_OK is returned. |
10315 | */ |
10316 | SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData); |
10317 | |
10318 | /* |
10319 | ** CAPI3REF: Obtain A Composite Changeset From A Changegroup |
10320 | ** METHOD: sqlite3_changegroup |
10321 | ** |
10322 | ** Obtain a buffer containing a changeset (or patchset) representing the |
10323 | ** current contents of the changegroup. If the inputs to the changegroup |
10324 | ** were themselves changesets, the output is a changeset. Or, if the |
10325 | ** inputs were patchsets, the output is also a patchset. |
10326 | ** |
10327 | ** As with the output of the sqlite3session_changeset() and |
10328 | ** sqlite3session_patchset() functions, all changes related to a single |
10329 | ** table are grouped together in the output of this function. Tables appear |
10330 | ** in the same order as for the very first changeset added to the changegroup. |
10331 | ** If the second or subsequent changesets added to the changegroup contain |
10332 | ** changes for tables that do not appear in the first changeset, they are |
10333 | ** appended onto the end of the output changeset, again in the order in |
10334 | ** which they are first encountered. |
10335 | ** |
10336 | ** If an error occurs, an SQLite error code is returned and the output |
10337 | ** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK |
10338 | ** is returned and the output variables are set to the size of and a |
10339 | ** pointer to the output buffer, respectively. In this case it is the |
10340 | ** responsibility of the caller to eventually free the buffer using a |
10341 | ** call to sqlite3_free(). |
10342 | */ |
10343 | SQLITE_API int sqlite3changegroup_output( |
10344 | sqlite3_changegroup*, |
10345 | int *pnData, /* OUT: Size of output buffer in bytes */ |
10346 | void **ppData /* OUT: Pointer to output buffer */ |
10347 | ); |
10348 | |
10349 | /* |
10350 | ** CAPI3REF: Delete A Changegroup Object |
10351 | ** DESTRUCTOR: sqlite3_changegroup |
10352 | */ |
10353 | SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*); |
10354 | |
10355 | /* |
10356 | ** CAPI3REF: Apply A Changeset To A Database |
10357 | ** |
10358 | ** Apply a changeset or patchset to a database. These functions attempt to |
10359 | ** update the "main" database attached to handle db with the changes found in |
10360 | ** the changeset passed via the second and third arguments. |
10361 | ** |
10362 | ** The fourth argument (xFilter) passed to these functions is the "filter |
10363 | ** callback". If it is not NULL, then for each table affected by at least one |
10364 | ** change in the changeset, the filter callback is invoked with |
10365 | ** the table name as the second argument, and a copy of the context pointer |
10366 | ** passed as the sixth argument as the first. If the "filter callback" |
10367 | ** returns zero, then no attempt is made to apply any changes to the table. |
10368 | ** Otherwise, if the return value is non-zero or the xFilter argument to |
10369 | ** is NULL, all changes related to the table are attempted. |
10370 | ** |
10371 | ** For each table that is not excluded by the filter callback, this function |
10372 | ** tests that the target database contains a compatible table. A table is |
10373 | ** considered compatible if all of the following are true: |
10374 | ** |
10375 | ** <ul> |
10376 | ** <li> The table has the same name as the name recorded in the |
10377 | ** changeset, and |
10378 | ** <li> The table has at least as many columns as recorded in the |
10379 | ** changeset, and |
10380 | ** <li> The table has primary key columns in the same position as |
10381 | ** recorded in the changeset. |
10382 | ** </ul> |
10383 | ** |
10384 | ** If there is no compatible table, it is not an error, but none of the |
10385 | ** changes associated with the table are applied. A warning message is issued |
10386 | ** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most |
10387 | ** one such warning is issued for each table in the changeset. |
10388 | ** |
10389 | ** For each change for which there is a compatible table, an attempt is made |
10390 | ** to modify the table contents according to the UPDATE, INSERT or DELETE |
10391 | ** change. If a change cannot be applied cleanly, the conflict handler |
10392 | ** function passed as the fifth argument to sqlite3changeset_apply() may be |
10393 | ** invoked. A description of exactly when the conflict handler is invoked for |
10394 | ** each type of change is below. |
10395 | ** |
10396 | ** Unlike the xFilter argument, xConflict may not be passed NULL. The results |
10397 | ** of passing anything other than a valid function pointer as the xConflict |
10398 | ** argument are undefined. |
10399 | ** |
10400 | ** Each time the conflict handler function is invoked, it must return one |
10401 | ** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or |
10402 | ** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned |
10403 | ** if the second argument passed to the conflict handler is either |
10404 | ** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler |
10405 | ** returns an illegal value, any changes already made are rolled back and |
10406 | ** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different |
10407 | ** actions are taken by sqlite3changeset_apply() depending on the value |
10408 | ** returned by each invocation of the conflict-handler function. Refer to |
10409 | ** the documentation for the three |
10410 | ** [SQLITE_CHANGESET_OMIT|available return values] for details. |
10411 | ** |
10412 | ** <dl> |
10413 | ** <dt>DELETE Changes<dd> |
10414 | ** For each DELETE change, the function checks if the target database |
10415 | ** contains a row with the same primary key value (or values) as the |
10416 | ** original row values stored in the changeset. If it does, and the values |
10417 | ** stored in all non-primary key columns also match the values stored in |
10418 | ** the changeset the row is deleted from the target database. |
10419 | ** |
10420 | ** If a row with matching primary key values is found, but one or more of |
10421 | ** the non-primary key fields contains a value different from the original |
10422 | ** row value stored in the changeset, the conflict-handler function is |
10423 | ** invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the |
10424 | ** database table has more columns than are recorded in the changeset, |
10425 | ** only the values of those non-primary key fields are compared against |
10426 | ** the current database contents - any trailing database table columns |
10427 | ** are ignored. |
10428 | ** |
10429 | ** If no row with matching primary key values is found in the database, |
10430 | ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] |
10431 | ** passed as the second argument. |
10432 | ** |
10433 | ** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT |
10434 | ** (which can only happen if a foreign key constraint is violated), the |
10435 | ** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT] |
10436 | ** passed as the second argument. This includes the case where the DELETE |
10437 | ** operation is attempted because an earlier call to the conflict handler |
10438 | ** function returned [SQLITE_CHANGESET_REPLACE]. |
10439 | ** |
10440 | ** <dt>INSERT Changes<dd> |
10441 | ** For each INSERT change, an attempt is made to insert the new row into |
10442 | ** the database. If the changeset row contains fewer fields than the |
10443 | ** database table, the trailing fields are populated with their default |
10444 | ** values. |
10445 | ** |
10446 | ** If the attempt to insert the row fails because the database already |
10447 | ** contains a row with the same primary key values, the conflict handler |
10448 | ** function is invoked with the second argument set to |
10449 | ** [SQLITE_CHANGESET_CONFLICT]. |
10450 | ** |
10451 | ** If the attempt to insert the row fails because of some other constraint |
10452 | ** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is |
10453 | ** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT]. |
10454 | ** This includes the case where the INSERT operation is re-attempted because |
10455 | ** an earlier call to the conflict handler function returned |
10456 | ** [SQLITE_CHANGESET_REPLACE]. |
10457 | ** |
10458 | ** <dt>UPDATE Changes<dd> |
10459 | ** For each UPDATE change, the function checks if the target database |
10460 | ** contains a row with the same primary key value (or values) as the |
10461 | ** original row values stored in the changeset. If it does, and the values |
10462 | ** stored in all modified non-primary key columns also match the values |
10463 | ** stored in the changeset the row is updated within the target database. |
10464 | ** |
10465 | ** If a row with matching primary key values is found, but one or more of |
10466 | ** the modified non-primary key fields contains a value different from an |
10467 | ** original row value stored in the changeset, the conflict-handler function |
10468 | ** is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since |
10469 | ** UPDATE changes only contain values for non-primary key fields that are |
10470 | ** to be modified, only those fields need to match the original values to |
10471 | ** avoid the SQLITE_CHANGESET_DATA conflict-handler callback. |
10472 | ** |
10473 | ** If no row with matching primary key values is found in the database, |
10474 | ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] |
10475 | ** passed as the second argument. |
10476 | ** |
10477 | ** If the UPDATE operation is attempted, but SQLite returns |
10478 | ** SQLITE_CONSTRAINT, the conflict-handler function is invoked with |
10479 | ** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument. |
10480 | ** This includes the case where the UPDATE operation is attempted after |
10481 | ** an earlier call to the conflict handler function returned |
10482 | ** [SQLITE_CHANGESET_REPLACE]. |
10483 | ** </dl> |
10484 | ** |
10485 | ** It is safe to execute SQL statements, including those that write to the |
10486 | ** table that the callback related to, from within the xConflict callback. |
10487 | ** This can be used to further customize the applications conflict |
10488 | ** resolution strategy. |
10489 | ** |
10490 | ** All changes made by these functions are enclosed in a savepoint transaction. |
10491 | ** If any other error (aside from a constraint failure when attempting to |
10492 | ** write to the target database) occurs, then the savepoint transaction is |
10493 | ** rolled back, restoring the target database to its original state, and an |
10494 | ** SQLite error code returned. |
10495 | ** |
10496 | ** If the output parameters (ppRebase) and (pnRebase) are non-NULL and |
10497 | ** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2() |
10498 | ** may set (*ppRebase) to point to a "rebase" that may be used with the |
10499 | ** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase) |
10500 | ** is set to the size of the buffer in bytes. It is the responsibility of the |
10501 | ** caller to eventually free any such buffer using sqlite3_free(). The buffer |
10502 | ** is only allocated and populated if one or more conflicts were encountered |
10503 | ** while applying the patchset. See comments surrounding the sqlite3_rebaser |
10504 | ** APIs for further details. |
10505 | ** |
10506 | ** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent |
10507 | ** may be modified by passing a combination of |
10508 | ** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter. |
10509 | ** |
10510 | ** Note that the sqlite3changeset_apply_v2() API is still <b>experimental</b> |
10511 | ** and therefore subject to change. |
10512 | */ |
10513 | SQLITE_API int sqlite3changeset_apply( |
10514 | sqlite3 *db, /* Apply change to "main" db of this handle */ |
10515 | int nChangeset, /* Size of changeset in bytes */ |
10516 | void *pChangeset, /* Changeset blob */ |
10517 | int(*xFilter)( |
10518 | void *pCtx, /* Copy of sixth arg to _apply() */ |
10519 | const char *zTab /* Table name */ |
10520 | ), |
10521 | int(*xConflict)( |
10522 | void *pCtx, /* Copy of sixth arg to _apply() */ |
10523 | int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ |
10524 | sqlite3_changeset_iter *p /* Handle describing change and conflict */ |
10525 | ), |
10526 | void *pCtx /* First argument passed to xConflict */ |
10527 | ); |
10528 | SQLITE_API int sqlite3changeset_apply_v2( |
10529 | sqlite3 *db, /* Apply change to "main" db of this handle */ |
10530 | int nChangeset, /* Size of changeset in bytes */ |
10531 | void *pChangeset, /* Changeset blob */ |
10532 | int(*xFilter)( |
10533 | void *pCtx, /* Copy of sixth arg to _apply() */ |
10534 | const char *zTab /* Table name */ |
10535 | ), |
10536 | int(*xConflict)( |
10537 | void *pCtx, /* Copy of sixth arg to _apply() */ |
10538 | int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ |
10539 | sqlite3_changeset_iter *p /* Handle describing change and conflict */ |
10540 | ), |
10541 | void *pCtx, /* First argument passed to xConflict */ |
10542 | void **ppRebase, int *pnRebase, /* OUT: Rebase data */ |
10543 | int flags /* Combination of SESSION_APPLY_* flags */ |
10544 | ); |
10545 | |
10546 | /* |
10547 | ** CAPI3REF: Flags for sqlite3changeset_apply_v2 |
10548 | ** |
10549 | ** The following flags may passed via the 9th parameter to |
10550 | ** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]: |
10551 | ** |
10552 | ** <dl> |
10553 | ** <dt>SQLITE_CHANGESETAPPLY_NOSAVEPOINT <dd> |
10554 | ** Usually, the sessions module encloses all operations performed by |
10555 | ** a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The |
10556 | ** SAVEPOINT is committed if the changeset or patchset is successfully |
10557 | ** applied, or rolled back if an error occurs. Specifying this flag |
10558 | ** causes the sessions module to omit this savepoint. In this case, if the |
10559 | ** caller has an open transaction or savepoint when apply_v2() is called, |
10560 | ** it may revert the partially applied changeset by rolling it back. |
10561 | */ |
10562 | #define SQLITE_CHANGESETAPPLY_NOSAVEPOINT 0x0001 |
10563 | |
10564 | /* |
10565 | ** CAPI3REF: Constants Passed To The Conflict Handler |
10566 | ** |
10567 | ** Values that may be passed as the second argument to a conflict-handler. |
10568 | ** |
10569 | ** <dl> |
10570 | ** <dt>SQLITE_CHANGESET_DATA<dd> |
10571 | ** The conflict handler is invoked with CHANGESET_DATA as the second argument |
10572 | ** when processing a DELETE or UPDATE change if a row with the required |
10573 | ** PRIMARY KEY fields is present in the database, but one or more other |
10574 | ** (non primary-key) fields modified by the update do not contain the |
10575 | ** expected "before" values. |
10576 | ** |
10577 | ** The conflicting row, in this case, is the database row with the matching |
10578 | ** primary key. |
10579 | ** |
10580 | ** <dt>SQLITE_CHANGESET_NOTFOUND<dd> |
10581 | ** The conflict handler is invoked with CHANGESET_NOTFOUND as the second |
10582 | ** argument when processing a DELETE or UPDATE change if a row with the |
10583 | ** required PRIMARY KEY fields is not present in the database. |
10584 | ** |
10585 | ** There is no conflicting row in this case. The results of invoking the |
10586 | ** sqlite3changeset_conflict() API are undefined. |
10587 | ** |
10588 | ** <dt>SQLITE_CHANGESET_CONFLICT<dd> |
10589 | ** CHANGESET_CONFLICT is passed as the second argument to the conflict |
10590 | ** handler while processing an INSERT change if the operation would result |
10591 | ** in duplicate primary key values. |
10592 | ** |
10593 | ** The conflicting row in this case is the database row with the matching |
10594 | ** primary key. |
10595 | ** |
10596 | ** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd> |
10597 | ** If foreign key handling is enabled, and applying a changeset leaves the |
10598 | ** database in a state containing foreign key violations, the conflict |
10599 | ** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument |
10600 | ** exactly once before the changeset is committed. If the conflict handler |
10601 | ** returns CHANGESET_OMIT, the changes, including those that caused the |
10602 | ** foreign key constraint violation, are committed. Or, if it returns |
10603 | ** CHANGESET_ABORT, the changeset is rolled back. |
10604 | ** |
10605 | ** No current or conflicting row information is provided. The only function |
10606 | ** it is possible to call on the supplied sqlite3_changeset_iter handle |
10607 | ** is sqlite3changeset_fk_conflicts(). |
10608 | ** |
10609 | ** <dt>SQLITE_CHANGESET_CONSTRAINT<dd> |
10610 | ** If any other constraint violation occurs while applying a change (i.e. |
10611 | ** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is |
10612 | ** invoked with CHANGESET_CONSTRAINT as the second argument. |
10613 | ** |
10614 | ** There is no conflicting row in this case. The results of invoking the |
10615 | ** sqlite3changeset_conflict() API are undefined. |
10616 | ** |
10617 | ** </dl> |
10618 | */ |
10619 | #define SQLITE_CHANGESET_DATA 1 |
10620 | #define SQLITE_CHANGESET_NOTFOUND 2 |
10621 | #define SQLITE_CHANGESET_CONFLICT 3 |
10622 | #define SQLITE_CHANGESET_CONSTRAINT 4 |
10623 | #define SQLITE_CHANGESET_FOREIGN_KEY 5 |
10624 | |
10625 | /* |
10626 | ** CAPI3REF: Constants Returned By The Conflict Handler |
10627 | ** |
10628 | ** A conflict handler callback must return one of the following three values. |
10629 | ** |
10630 | ** <dl> |
10631 | ** <dt>SQLITE_CHANGESET_OMIT<dd> |
10632 | ** If a conflict handler returns this value no special action is taken. The |
10633 | ** change that caused the conflict is not applied. The session module |
10634 | ** continues to the next change in the changeset. |
10635 | ** |
10636 | ** <dt>SQLITE_CHANGESET_REPLACE<dd> |
10637 | ** This value may only be returned if the second argument to the conflict |
10638 | ** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this |
10639 | ** is not the case, any changes applied so far are rolled back and the |
10640 | ** call to sqlite3changeset_apply() returns SQLITE_MISUSE. |
10641 | ** |
10642 | ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict |
10643 | ** handler, then the conflicting row is either updated or deleted, depending |
10644 | ** on the type of change. |
10645 | ** |
10646 | ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict |
10647 | ** handler, then the conflicting row is removed from the database and a |
10648 | ** second attempt to apply the change is made. If this second attempt fails, |
10649 | ** the original row is restored to the database before continuing. |
10650 | ** |
10651 | ** <dt>SQLITE_CHANGESET_ABORT<dd> |
10652 | ** If this value is returned, any changes applied so far are rolled back |
10653 | ** and the call to sqlite3changeset_apply() returns SQLITE_ABORT. |
10654 | ** </dl> |
10655 | */ |
10656 | #define SQLITE_CHANGESET_OMIT 0 |
10657 | #define SQLITE_CHANGESET_REPLACE 1 |
10658 | #define SQLITE_CHANGESET_ABORT 2 |
10659 | |
10660 | /* |
10661 | ** CAPI3REF: Rebasing changesets |
10662 | ** EXPERIMENTAL |
10663 | ** |
10664 | ** Suppose there is a site hosting a database in state S0. And that |
10665 | ** modifications are made that move that database to state S1 and a |
10666 | ** changeset recorded (the "local" changeset). Then, a changeset based |
10667 | ** on S0 is received from another site (the "remote" changeset) and |
10668 | ** applied to the database. The database is then in state |
10669 | ** (S1+"remote"), where the exact state depends on any conflict |
10670 | ** resolution decisions (OMIT or REPLACE) made while applying "remote". |
10671 | ** Rebasing a changeset is to update it to take those conflict |
10672 | ** resolution decisions into account, so that the same conflicts |
10673 | ** do not have to be resolved elsewhere in the network. |
10674 | ** |
10675 | ** For example, if both the local and remote changesets contain an |
10676 | ** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)": |
10677 | ** |
10678 | ** local: INSERT INTO t1 VALUES(1, 'v1'); |
10679 | ** remote: INSERT INTO t1 VALUES(1, 'v2'); |
10680 | ** |
10681 | ** and the conflict resolution is REPLACE, then the INSERT change is |
10682 | ** removed from the local changeset (it was overridden). Or, if the |
10683 | ** conflict resolution was "OMIT", then the local changeset is modified |
10684 | ** to instead contain: |
10685 | ** |
10686 | ** UPDATE t1 SET b = 'v2' WHERE a=1; |
10687 | ** |
10688 | ** Changes within the local changeset are rebased as follows: |
10689 | ** |
10690 | ** <dl> |
10691 | ** <dt>Local INSERT<dd> |
10692 | ** This may only conflict with a remote INSERT. If the conflict |
10693 | ** resolution was OMIT, then add an UPDATE change to the rebased |
10694 | ** changeset. Or, if the conflict resolution was REPLACE, add |
10695 | ** nothing to the rebased changeset. |
10696 | ** |
10697 | ** <dt>Local DELETE<dd> |
10698 | ** This may conflict with a remote UPDATE or DELETE. In both cases the |
10699 | ** only possible resolution is OMIT. If the remote operation was a |
10700 | ** DELETE, then add no change to the rebased changeset. If the remote |
10701 | ** operation was an UPDATE, then the old.* fields of change are updated |
10702 | ** to reflect the new.* values in the UPDATE. |
10703 | ** |
10704 | ** <dt>Local UPDATE<dd> |
10705 | ** This may conflict with a remote UPDATE or DELETE. If it conflicts |
10706 | ** with a DELETE, and the conflict resolution was OMIT, then the update |
10707 | ** is changed into an INSERT. Any undefined values in the new.* record |
10708 | ** from the update change are filled in using the old.* values from |
10709 | ** the conflicting DELETE. Or, if the conflict resolution was REPLACE, |
10710 | ** the UPDATE change is simply omitted from the rebased changeset. |
10711 | ** |
10712 | ** If conflict is with a remote UPDATE and the resolution is OMIT, then |
10713 | ** the old.* values are rebased using the new.* values in the remote |
10714 | ** change. Or, if the resolution is REPLACE, then the change is copied |
10715 | ** into the rebased changeset with updates to columns also updated by |
10716 | ** the conflicting remote UPDATE removed. If this means no columns would |
10717 | ** be updated, the change is omitted. |
10718 | ** </dl> |
10719 | ** |
10720 | ** A local change may be rebased against multiple remote changes |
10721 | ** simultaneously. If a single key is modified by multiple remote |
10722 | ** changesets, they are combined as follows before the local changeset |
10723 | ** is rebased: |
10724 | ** |
10725 | ** <ul> |
10726 | ** <li> If there has been one or more REPLACE resolutions on a |
10727 | ** key, it is rebased according to a REPLACE. |
10728 | ** |
10729 | ** <li> If there have been no REPLACE resolutions on a key, then |
10730 | ** the local changeset is rebased according to the most recent |
10731 | ** of the OMIT resolutions. |
10732 | ** </ul> |
10733 | ** |
10734 | ** Note that conflict resolutions from multiple remote changesets are |
10735 | ** combined on a per-field basis, not per-row. This means that in the |
10736 | ** case of multiple remote UPDATE operations, some fields of a single |
10737 | ** local change may be rebased for REPLACE while others are rebased for |
10738 | ** OMIT. |
10739 | ** |
10740 | ** In order to rebase a local changeset, the remote changeset must first |
10741 | ** be applied to the local database using sqlite3changeset_apply_v2() and |
10742 | ** the buffer of rebase information captured. Then: |
10743 | ** |
10744 | ** <ol> |
10745 | ** <li> An sqlite3_rebaser object is created by calling |
10746 | ** sqlite3rebaser_create(). |
10747 | ** <li> The new object is configured with the rebase buffer obtained from |
10748 | ** sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure(). |
10749 | ** If the local changeset is to be rebased against multiple remote |
10750 | ** changesets, then sqlite3rebaser_configure() should be called |
10751 | ** multiple times, in the same order that the multiple |
10752 | ** sqlite3changeset_apply_v2() calls were made. |
10753 | ** <li> Each local changeset is rebased by calling sqlite3rebaser_rebase(). |
10754 | ** <li> The sqlite3_rebaser object is deleted by calling |
10755 | ** sqlite3rebaser_delete(). |
10756 | ** </ol> |
10757 | */ |
10758 | typedef struct sqlite3_rebaser sqlite3_rebaser; |
10759 | |
10760 | /* |
10761 | ** CAPI3REF: Create a changeset rebaser object. |
10762 | ** EXPERIMENTAL |
10763 | ** |
10764 | ** Allocate a new changeset rebaser object. If successful, set (*ppNew) to |
10765 | ** point to the new object and return SQLITE_OK. Otherwise, if an error |
10766 | ** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew) |
10767 | ** to NULL. |
10768 | */ |
10769 | SQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew); |
10770 | |
10771 | /* |
10772 | ** CAPI3REF: Configure a changeset rebaser object. |
10773 | ** EXPERIMENTAL |
10774 | ** |
10775 | ** Configure the changeset rebaser object to rebase changesets according |
10776 | ** to the conflict resolutions described by buffer pRebase (size nRebase |
10777 | ** bytes), which must have been obtained from a previous call to |
10778 | ** sqlite3changeset_apply_v2(). |
10779 | */ |
10780 | SQLITE_API int sqlite3rebaser_configure( |
10781 | sqlite3_rebaser*, |
10782 | int nRebase, const void *pRebase |
10783 | ); |
10784 | |
10785 | /* |
10786 | ** CAPI3REF: Rebase a changeset |
10787 | ** EXPERIMENTAL |
10788 | ** |
10789 | ** Argument pIn must point to a buffer containing a changeset nIn bytes |
10790 | ** in size. This function allocates and populates a buffer with a copy |
10791 | ** of the changeset rebased rebased according to the configuration of the |
10792 | ** rebaser object passed as the first argument. If successful, (*ppOut) |
10793 | ** is set to point to the new buffer containing the rebased changset and |
10794 | ** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the |
10795 | ** responsibility of the caller to eventually free the new buffer using |
10796 | ** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut) |
10797 | ** are set to zero and an SQLite error code returned. |
10798 | */ |
10799 | SQLITE_API int sqlite3rebaser_rebase( |
10800 | sqlite3_rebaser*, |
10801 | int nIn, const void *pIn, |
10802 | int *pnOut, void **ppOut |
10803 | ); |
10804 | |
10805 | /* |
10806 | ** CAPI3REF: Delete a changeset rebaser object. |
10807 | ** EXPERIMENTAL |
10808 | ** |
10809 | ** Delete the changeset rebaser object and all associated resources. There |
10810 | ** should be one call to this function for each successful invocation |
10811 | ** of sqlite3rebaser_create(). |
10812 | */ |
10813 | SQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p); |
10814 | |
10815 | /* |
10816 | ** CAPI3REF: Streaming Versions of API functions. |
10817 | ** |
10818 | ** The six streaming API xxx_strm() functions serve similar purposes to the |
10819 | ** corresponding non-streaming API functions: |
10820 | ** |
10821 | ** <table border=1 style="margin-left:8ex;margin-right:8ex"> |
10822 | ** <tr><th>Streaming function<th>Non-streaming equivalent</th> |
10823 | ** <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply] |
10824 | ** <tr><td>sqlite3changeset_apply_strm_v2<td>[sqlite3changeset_apply_v2] |
10825 | ** <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat] |
10826 | ** <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert] |
10827 | ** <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start] |
10828 | ** <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset] |
10829 | ** <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset] |
10830 | ** </table> |
10831 | ** |
10832 | ** Non-streaming functions that accept changesets (or patchsets) as input |
10833 | ** require that the entire changeset be stored in a single buffer in memory. |
10834 | ** Similarly, those that return a changeset or patchset do so by returning |
10835 | ** a pointer to a single large buffer allocated using sqlite3_malloc(). |
10836 | ** Normally this is convenient. However, if an application running in a |
10837 | ** low-memory environment is required to handle very large changesets, the |
10838 | ** large contiguous memory allocations required can become onerous. |
10839 | ** |
10840 | ** In order to avoid this problem, instead of a single large buffer, input |
10841 | ** is passed to a streaming API functions by way of a callback function that |
10842 | ** the sessions module invokes to incrementally request input data as it is |
10843 | ** required. In all cases, a pair of API function parameters such as |
10844 | ** |
10845 | ** <pre> |
10846 | ** int nChangeset, |
10847 | ** void *pChangeset, |
10848 | ** </pre> |
10849 | ** |
10850 | ** Is replaced by: |
10851 | ** |
10852 | ** <pre> |
10853 | ** int (*xInput)(void *pIn, void *pData, int *pnData), |
10854 | ** void *pIn, |
10855 | ** </pre> |
10856 | ** |
10857 | ** Each time the xInput callback is invoked by the sessions module, the first |
10858 | ** argument passed is a copy of the supplied pIn context pointer. The second |
10859 | ** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no |
10860 | ** error occurs the xInput method should copy up to (*pnData) bytes of data |
10861 | ** into the buffer and set (*pnData) to the actual number of bytes copied |
10862 | ** before returning SQLITE_OK. If the input is completely exhausted, (*pnData) |
10863 | ** should be set to zero to indicate this. Or, if an error occurs, an SQLite |
10864 | ** error code should be returned. In all cases, if an xInput callback returns |
10865 | ** an error, all processing is abandoned and the streaming API function |
10866 | ** returns a copy of the error code to the caller. |
10867 | ** |
10868 | ** In the case of sqlite3changeset_start_strm(), the xInput callback may be |
10869 | ** invoked by the sessions module at any point during the lifetime of the |
10870 | ** iterator. If such an xInput callback returns an error, the iterator enters |
10871 | ** an error state, whereby all subsequent calls to iterator functions |
10872 | ** immediately fail with the same error code as returned by xInput. |
10873 | ** |
10874 | ** Similarly, streaming API functions that return changesets (or patchsets) |
10875 | ** return them in chunks by way of a callback function instead of via a |
10876 | ** pointer to a single large buffer. In this case, a pair of parameters such |
10877 | ** as: |
10878 | ** |
10879 | ** <pre> |
10880 | ** int *pnChangeset, |
10881 | ** void **ppChangeset, |
10882 | ** </pre> |
10883 | ** |
10884 | ** Is replaced by: |
10885 | ** |
10886 | ** <pre> |
10887 | ** int (*xOutput)(void *pOut, const void *pData, int nData), |
10888 | ** void *pOut |
10889 | ** </pre> |
10890 | ** |
10891 | ** The xOutput callback is invoked zero or more times to return data to |
10892 | ** the application. The first parameter passed to each call is a copy of the |
10893 | ** pOut pointer supplied by the application. The second parameter, pData, |
10894 | ** points to a buffer nData bytes in size containing the chunk of output |
10895 | ** data being returned. If the xOutput callback successfully processes the |
10896 | ** supplied data, it should return SQLITE_OK to indicate success. Otherwise, |
10897 | ** it should return some other SQLite error code. In this case processing |
10898 | ** is immediately abandoned and the streaming API function returns a copy |
10899 | ** of the xOutput error code to the application. |
10900 | ** |
10901 | ** The sessions module never invokes an xOutput callback with the third |
10902 | ** parameter set to a value less than or equal to zero. Other than this, |
10903 | ** no guarantees are made as to the size of the chunks of data returned. |
10904 | */ |
10905 | SQLITE_API int sqlite3changeset_apply_strm( |
10906 | sqlite3 *db, /* Apply change to "main" db of this handle */ |
10907 | int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ |
10908 | void *pIn, /* First arg for xInput */ |
10909 | int(*xFilter)( |
10910 | void *pCtx, /* Copy of sixth arg to _apply() */ |
10911 | const char *zTab /* Table name */ |
10912 | ), |
10913 | int(*xConflict)( |
10914 | void *pCtx, /* Copy of sixth arg to _apply() */ |
10915 | int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ |
10916 | sqlite3_changeset_iter *p /* Handle describing change and conflict */ |
10917 | ), |
10918 | void *pCtx /* First argument passed to xConflict */ |
10919 | ); |
10920 | SQLITE_API int sqlite3changeset_apply_v2_strm( |
10921 | sqlite3 *db, /* Apply change to "main" db of this handle */ |
10922 | int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ |
10923 | void *pIn, /* First arg for xInput */ |
10924 | int(*xFilter)( |
10925 | void *pCtx, /* Copy of sixth arg to _apply() */ |
10926 | const char *zTab /* Table name */ |
10927 | ), |
10928 | int(*xConflict)( |
10929 | void *pCtx, /* Copy of sixth arg to _apply() */ |
10930 | int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ |
10931 | sqlite3_changeset_iter *p /* Handle describing change and conflict */ |
10932 | ), |
10933 | void *pCtx, /* First argument passed to xConflict */ |
10934 | void **ppRebase, int *pnRebase, |
10935 | int flags |
10936 | ); |
10937 | SQLITE_API int sqlite3changeset_concat_strm( |
10938 | int (*xInputA)(void *pIn, void *pData, int *pnData), |
10939 | void *pInA, |
10940 | int (*xInputB)(void *pIn, void *pData, int *pnData), |
10941 | void *pInB, |
10942 | int (*xOutput)(void *pOut, const void *pData, int nData), |
10943 | void *pOut |
10944 | ); |
10945 | SQLITE_API int sqlite3changeset_invert_strm( |
10946 | int (*xInput)(void *pIn, void *pData, int *pnData), |
10947 | void *pIn, |
10948 | int (*xOutput)(void *pOut, const void *pData, int nData), |
10949 | void *pOut |
10950 | ); |
10951 | SQLITE_API int sqlite3changeset_start_strm( |
10952 | sqlite3_changeset_iter **pp, |
10953 | int (*xInput)(void *pIn, void *pData, int *pnData), |
10954 | void *pIn |
10955 | ); |
10956 | SQLITE_API int sqlite3session_changeset_strm( |
10957 | sqlite3_session *pSession, |
10958 | int (*xOutput)(void *pOut, const void *pData, int nData), |
10959 | void *pOut |
10960 | ); |
10961 | SQLITE_API int sqlite3session_patchset_strm( |
10962 | sqlite3_session *pSession, |
10963 | int (*xOutput)(void *pOut, const void *pData, int nData), |
10964 | void *pOut |
10965 | ); |
10966 | SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*, |
10967 | int (*xInput)(void *pIn, void *pData, int *pnData), |
10968 | void *pIn |
10969 | ); |
10970 | SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*, |
10971 | int (*xOutput)(void *pOut, const void *pData, int nData), |
10972 | void *pOut |
10973 | ); |
10974 | SQLITE_API int sqlite3rebaser_rebase_strm( |
10975 | sqlite3_rebaser *pRebaser, |
10976 | int (*xInput)(void *pIn, void *pData, int *pnData), |
10977 | void *pIn, |
10978 | int (*xOutput)(void *pOut, const void *pData, int nData), |
10979 | void *pOut |
10980 | ); |
10981 | |
10982 | |
10983 | /* |
10984 | ** Make sure we can call this stuff from C++. |
10985 | */ |
10986 | #ifdef __cplusplus |
10987 | } |
10988 | #endif |
10989 | |
10990 | #endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */ |
10991 | |
10992 | /******** End of sqlite3session.h *********/ |
10993 | /******** Begin file fts5.h *********/ |
10994 | /* |
10995 | ** 2014 May 31 |
10996 | ** |
10997 | ** The author disclaims copyright to this source code. In place of |
10998 | ** a legal notice, here is a blessing: |
10999 | ** |
11000 | ** May you do good and not evil. |
11001 | ** May you find forgiveness for yourself and forgive others. |
11002 | ** May you share freely, never taking more than you give. |
11003 | ** |
11004 | ****************************************************************************** |
11005 | ** |
11006 | ** Interfaces to extend FTS5. Using the interfaces defined in this file, |
11007 | ** FTS5 may be extended with: |
11008 | ** |
11009 | ** * custom tokenizers, and |
11010 | ** * custom auxiliary functions. |
11011 | */ |
11012 | |
11013 | |
11014 | #ifndef _FTS5_H |
11015 | #define _FTS5_H |
11016 | |
11017 | |
11018 | #ifdef __cplusplus |
11019 | extern "C" { |
11020 | #endif |
11021 | |
11022 | /************************************************************************* |
11023 | ** CUSTOM AUXILIARY FUNCTIONS |
11024 | ** |
11025 | ** Virtual table implementations may overload SQL functions by implementing |
11026 | ** the sqlite3_module.xFindFunction() method. |
11027 | */ |
11028 | |
11029 | typedef struct Fts5ExtensionApi Fts5ExtensionApi; |
11030 | typedef struct Fts5Context Fts5Context; |
11031 | typedef struct Fts5PhraseIter Fts5PhraseIter; |
11032 | |
11033 | typedef void (*fts5_extension_function)( |
11034 | const Fts5ExtensionApi *pApi, /* API offered by current FTS version */ |
11035 | Fts5Context *pFts, /* First arg to pass to pApi functions */ |
11036 | sqlite3_context *pCtx, /* Context for returning result/error */ |
11037 | int nVal, /* Number of values in apVal[] array */ |
11038 | sqlite3_value **apVal /* Array of trailing arguments */ |
11039 | ); |
11040 | |
11041 | struct Fts5PhraseIter { |
11042 | const unsigned char *a; |
11043 | const unsigned char *b; |
11044 | }; |
11045 | |
11046 | /* |
11047 | ** EXTENSION API FUNCTIONS |
11048 | ** |
11049 | ** xUserData(pFts): |
11050 | ** Return a copy of the context pointer the extension function was |
11051 | ** registered with. |
11052 | ** |
11053 | ** xColumnTotalSize(pFts, iCol, pnToken): |
11054 | ** If parameter iCol is less than zero, set output variable *pnToken |
11055 | ** to the total number of tokens in the FTS5 table. Or, if iCol is |
11056 | ** non-negative but less than the number of columns in the table, return |
11057 | ** the total number of tokens in column iCol, considering all rows in |
11058 | ** the FTS5 table. |
11059 | ** |
11060 | ** If parameter iCol is greater than or equal to the number of columns |
11061 | ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. |
11062 | ** an OOM condition or IO error), an appropriate SQLite error code is |
11063 | ** returned. |
11064 | ** |
11065 | ** xColumnCount(pFts): |
11066 | ** Return the number of columns in the table. |
11067 | ** |
11068 | ** xColumnSize(pFts, iCol, pnToken): |
11069 | ** If parameter iCol is less than zero, set output variable *pnToken |
11070 | ** to the total number of tokens in the current row. Or, if iCol is |
11071 | ** non-negative but less than the number of columns in the table, set |
11072 | ** *pnToken to the number of tokens in column iCol of the current row. |
11073 | ** |
11074 | ** If parameter iCol is greater than or equal to the number of columns |
11075 | ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. |
11076 | ** an OOM condition or IO error), an appropriate SQLite error code is |
11077 | ** returned. |
11078 | ** |
11079 | ** This function may be quite inefficient if used with an FTS5 table |
11080 | ** created with the "columnsize=0" option. |
11081 | ** |
11082 | ** xColumnText: |
11083 | ** This function attempts to retrieve the text of column iCol of the |
11084 | ** current document. If successful, (*pz) is set to point to a buffer |
11085 | ** containing the text in utf-8 encoding, (*pn) is set to the size in bytes |
11086 | ** (not characters) of the buffer and SQLITE_OK is returned. Otherwise, |
11087 | ** if an error occurs, an SQLite error code is returned and the final values |
11088 | ** of (*pz) and (*pn) are undefined. |
11089 | ** |
11090 | ** xPhraseCount: |
11091 | ** Returns the number of phrases in the current query expression. |
11092 | ** |
11093 | ** xPhraseSize: |
11094 | ** Returns the number of tokens in phrase iPhrase of the query. Phrases |
11095 | ** are numbered starting from zero. |
11096 | ** |
11097 | ** xInstCount: |
11098 | ** Set *pnInst to the total number of occurrences of all phrases within |
11099 | ** the query within the current row. Return SQLITE_OK if successful, or |
11100 | ** an error code (i.e. SQLITE_NOMEM) if an error occurs. |
11101 | ** |
11102 | ** This API can be quite slow if used with an FTS5 table created with the |
11103 | ** "detail=none" or "detail=column" option. If the FTS5 table is created |
11104 | ** with either "detail=none" or "detail=column" and "content=" option |
11105 | ** (i.e. if it is a contentless table), then this API always returns 0. |
11106 | ** |
11107 | ** xInst: |
11108 | ** Query for the details of phrase match iIdx within the current row. |
11109 | ** Phrase matches are numbered starting from zero, so the iIdx argument |
11110 | ** should be greater than or equal to zero and smaller than the value |
11111 | ** output by xInstCount(). |
11112 | ** |
11113 | ** Usually, output parameter *piPhrase is set to the phrase number, *piCol |
11114 | ** to the column in which it occurs and *piOff the token offset of the |
11115 | ** first token of the phrase. The exception is if the table was created |
11116 | ** with the offsets=0 option specified. In this case *piOff is always |
11117 | ** set to -1. |
11118 | ** |
11119 | ** Returns SQLITE_OK if successful, or an error code (i.e. SQLITE_NOMEM) |
11120 | ** if an error occurs. |
11121 | ** |
11122 | ** This API can be quite slow if used with an FTS5 table created with the |
11123 | ** "detail=none" or "detail=column" option. |
11124 | ** |
11125 | ** xRowid: |
11126 | ** Returns the rowid of the current row. |
11127 | ** |
11128 | ** xTokenize: |
11129 | ** Tokenize text using the tokenizer belonging to the FTS5 table. |
11130 | ** |
11131 | ** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback): |
11132 | ** This API function is used to query the FTS table for phrase iPhrase |
11133 | ** of the current query. Specifically, a query equivalent to: |
11134 | ** |
11135 | ** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid |
11136 | ** |
11137 | ** with $p set to a phrase equivalent to the phrase iPhrase of the |
11138 | ** current query is executed. Any column filter that applies to |
11139 | ** phrase iPhrase of the current query is included in $p. For each |
11140 | ** row visited, the callback function passed as the fourth argument |
11141 | ** is invoked. The context and API objects passed to the callback |
11142 | ** function may be used to access the properties of each matched row. |
11143 | ** Invoking Api.xUserData() returns a copy of the pointer passed as |
11144 | ** the third argument to pUserData. |
11145 | ** |
11146 | ** If the callback function returns any value other than SQLITE_OK, the |
11147 | ** query is abandoned and the xQueryPhrase function returns immediately. |
11148 | ** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK. |
11149 | ** Otherwise, the error code is propagated upwards. |
11150 | ** |
11151 | ** If the query runs to completion without incident, SQLITE_OK is returned. |
11152 | ** Or, if some error occurs before the query completes or is aborted by |
11153 | ** the callback, an SQLite error code is returned. |
11154 | ** |
11155 | ** |
11156 | ** xSetAuxdata(pFts5, pAux, xDelete) |
11157 | ** |
11158 | ** Save the pointer passed as the second argument as the extension functions |
11159 | ** "auxiliary data". The pointer may then be retrieved by the current or any |
11160 | ** future invocation of the same fts5 extension function made as part of |
11161 | ** of the same MATCH query using the xGetAuxdata() API. |
11162 | ** |
11163 | ** Each extension function is allocated a single auxiliary data slot for |
11164 | ** each FTS query (MATCH expression). If the extension function is invoked |
11165 | ** more than once for a single FTS query, then all invocations share a |
11166 | ** single auxiliary data context. |
11167 | ** |
11168 | ** If there is already an auxiliary data pointer when this function is |
11169 | ** invoked, then it is replaced by the new pointer. If an xDelete callback |
11170 | ** was specified along with the original pointer, it is invoked at this |
11171 | ** point. |
11172 | ** |
11173 | ** The xDelete callback, if one is specified, is also invoked on the |
11174 | ** auxiliary data pointer after the FTS5 query has finished. |
11175 | ** |
11176 | ** If an error (e.g. an OOM condition) occurs within this function, an |
11177 | ** the auxiliary data is set to NULL and an error code returned. If the |
11178 | ** xDelete parameter was not NULL, it is invoked on the auxiliary data |
11179 | ** pointer before returning. |
11180 | ** |
11181 | ** |
11182 | ** xGetAuxdata(pFts5, bClear) |
11183 | ** |
11184 | ** Returns the current auxiliary data pointer for the fts5 extension |
11185 | ** function. See the xSetAuxdata() method for details. |
11186 | ** |
11187 | ** If the bClear argument is non-zero, then the auxiliary data is cleared |
11188 | ** (set to NULL) before this function returns. In this case the xDelete, |
11189 | ** if any, is not invoked. |
11190 | ** |
11191 | ** |
11192 | ** xRowCount(pFts5, pnRow) |
11193 | ** |
11194 | ** This function is used to retrieve the total number of rows in the table. |
11195 | ** In other words, the same value that would be returned by: |
11196 | ** |
11197 | ** SELECT count(*) FROM ftstable; |
11198 | ** |
11199 | ** xPhraseFirst() |
11200 | ** This function is used, along with type Fts5PhraseIter and the xPhraseNext |
11201 | ** method, to iterate through all instances of a single query phrase within |
11202 | ** the current row. This is the same information as is accessible via the |
11203 | ** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient |
11204 | ** to use, this API may be faster under some circumstances. To iterate |
11205 | ** through instances of phrase iPhrase, use the following code: |
11206 | ** |
11207 | ** Fts5PhraseIter iter; |
11208 | ** int iCol, iOff; |
11209 | ** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff); |
11210 | ** iCol>=0; |
11211 | ** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff) |
11212 | ** ){ |
11213 | ** // An instance of phrase iPhrase at offset iOff of column iCol |
11214 | ** } |
11215 | ** |
11216 | ** The Fts5PhraseIter structure is defined above. Applications should not |
11217 | ** modify this structure directly - it should only be used as shown above |
11218 | ** with the xPhraseFirst() and xPhraseNext() API methods (and by |
11219 | ** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below). |
11220 | ** |
11221 | ** This API can be quite slow if used with an FTS5 table created with the |
11222 | ** "detail=none" or "detail=column" option. If the FTS5 table is created |
11223 | ** with either "detail=none" or "detail=column" and "content=" option |
11224 | ** (i.e. if it is a contentless table), then this API always iterates |
11225 | ** through an empty set (all calls to xPhraseFirst() set iCol to -1). |
11226 | ** |
11227 | ** xPhraseNext() |
11228 | ** See xPhraseFirst above. |
11229 | ** |
11230 | ** xPhraseFirstColumn() |
11231 | ** This function and xPhraseNextColumn() are similar to the xPhraseFirst() |
11232 | ** and xPhraseNext() APIs described above. The difference is that instead |
11233 | ** of iterating through all instances of a phrase in the current row, these |
11234 | ** APIs are used to iterate through the set of columns in the current row |
11235 | ** that contain one or more instances of a specified phrase. For example: |
11236 | ** |
11237 | ** Fts5PhraseIter iter; |
11238 | ** int iCol; |
11239 | ** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol); |
11240 | ** iCol>=0; |
11241 | ** pApi->xPhraseNextColumn(pFts, &iter, &iCol) |
11242 | ** ){ |
11243 | ** // Column iCol contains at least one instance of phrase iPhrase |
11244 | ** } |
11245 | ** |
11246 | ** This API can be quite slow if used with an FTS5 table created with the |
11247 | ** "detail=none" option. If the FTS5 table is created with either |
11248 | ** "detail=none" "content=" option (i.e. if it is a contentless table), |
11249 | ** then this API always iterates through an empty set (all calls to |
11250 | ** xPhraseFirstColumn() set iCol to -1). |
11251 | ** |
11252 | ** The information accessed using this API and its companion |
11253 | ** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext |
11254 | ** (or xInst/xInstCount). The chief advantage of this API is that it is |
11255 | ** significantly more efficient than those alternatives when used with |
11256 | ** "detail=column" tables. |
11257 | ** |
11258 | ** xPhraseNextColumn() |
11259 | ** See xPhraseFirstColumn above. |
11260 | */ |
11261 | struct Fts5ExtensionApi { |
11262 | int iVersion; /* Currently always set to 3 */ |
11263 | |
11264 | void *(*xUserData)(Fts5Context*); |
11265 | |
11266 | int (*xColumnCount)(Fts5Context*); |
11267 | int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow); |
11268 | int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken); |
11269 | |
11270 | int (*xTokenize)(Fts5Context*, |
11271 | const char *pText, int nText, /* Text to tokenize */ |
11272 | void *pCtx, /* Context passed to xToken() */ |
11273 | int (*xToken)(void*, int, const char*, int, int, int) /* Callback */ |
11274 | ); |
11275 | |
11276 | int (*xPhraseCount)(Fts5Context*); |
11277 | int (*xPhraseSize)(Fts5Context*, int iPhrase); |
11278 | |
11279 | int (*xInstCount)(Fts5Context*, int *pnInst); |
11280 | int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff); |
11281 | |
11282 | sqlite3_int64 (*xRowid)(Fts5Context*); |
11283 | int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn); |
11284 | int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken); |
11285 | |
11286 | int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData, |
11287 | int(*)(const Fts5ExtensionApi*,Fts5Context*,void*) |
11288 | ); |
11289 | int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*)); |
11290 | void *(*xGetAuxdata)(Fts5Context*, int bClear); |
11291 | |
11292 | int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*); |
11293 | void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff); |
11294 | |
11295 | int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*); |
11296 | void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol); |
11297 | }; |
11298 | |
11299 | /* |
11300 | ** CUSTOM AUXILIARY FUNCTIONS |
11301 | *************************************************************************/ |
11302 | |
11303 | /************************************************************************* |
11304 | ** CUSTOM TOKENIZERS |
11305 | ** |
11306 | ** Applications may also register custom tokenizer types. A tokenizer |
11307 | ** is registered by providing fts5 with a populated instance of the |
11308 | ** following structure. All structure methods must be defined, setting |
11309 | ** any member of the fts5_tokenizer struct to NULL leads to undefined |
11310 | ** behaviour. The structure methods are expected to function as follows: |
11311 | ** |
11312 | ** xCreate: |
11313 | ** This function is used to allocate and initialize a tokenizer instance. |
11314 | ** A tokenizer instance is required to actually tokenize text. |
11315 | ** |
11316 | ** The first argument passed to this function is a copy of the (void*) |
11317 | ** pointer provided by the application when the fts5_tokenizer object |
11318 | ** was registered with FTS5 (the third argument to xCreateTokenizer()). |
11319 | ** The second and third arguments are an array of nul-terminated strings |
11320 | ** containing the tokenizer arguments, if any, specified following the |
11321 | ** tokenizer name as part of the CREATE VIRTUAL TABLE statement used |
11322 | ** to create the FTS5 table. |
11323 | ** |
11324 | ** The final argument is an output variable. If successful, (*ppOut) |
11325 | ** should be set to point to the new tokenizer handle and SQLITE_OK |
11326 | ** returned. If an error occurs, some value other than SQLITE_OK should |
11327 | ** be returned. In this case, fts5 assumes that the final value of *ppOut |
11328 | ** is undefined. |
11329 | ** |
11330 | ** xDelete: |
11331 | ** This function is invoked to delete a tokenizer handle previously |
11332 | ** allocated using xCreate(). Fts5 guarantees that this function will |
11333 | ** be invoked exactly once for each successful call to xCreate(). |
11334 | ** |
11335 | ** xTokenize: |
11336 | ** This function is expected to tokenize the nText byte string indicated |
11337 | ** by argument pText. pText may or may not be nul-terminated. The first |
11338 | ** argument passed to this function is a pointer to an Fts5Tokenizer object |
11339 | ** returned by an earlier call to xCreate(). |
11340 | ** |
11341 | ** The second argument indicates the reason that FTS5 is requesting |
11342 | ** tokenization of the supplied text. This is always one of the following |
11343 | ** four values: |
11344 | ** |
11345 | ** <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into |
11346 | ** or removed from the FTS table. The tokenizer is being invoked to |
11347 | ** determine the set of tokens to add to (or delete from) the |
11348 | ** FTS index. |
11349 | ** |
11350 | ** <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed |
11351 | ** against the FTS index. The tokenizer is being called to tokenize |
11352 | ** a bareword or quoted string specified as part of the query. |
11353 | ** |
11354 | ** <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as |
11355 | ** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is |
11356 | ** followed by a "*" character, indicating that the last token |
11357 | ** returned by the tokenizer will be treated as a token prefix. |
11358 | ** |
11359 | ** <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to |
11360 | ** satisfy an fts5_api.xTokenize() request made by an auxiliary |
11361 | ** function. Or an fts5_api.xColumnSize() request made by the same |
11362 | ** on a columnsize=0 database. |
11363 | ** </ul> |
11364 | ** |
11365 | ** For each token in the input string, the supplied callback xToken() must |
11366 | ** be invoked. The first argument to it should be a copy of the pointer |
11367 | ** passed as the second argument to xTokenize(). The third and fourth |
11368 | ** arguments are a pointer to a buffer containing the token text, and the |
11369 | ** size of the token in bytes. The 4th and 5th arguments are the byte offsets |
11370 | ** of the first byte of and first byte immediately following the text from |
11371 | ** which the token is derived within the input. |
11372 | ** |
11373 | ** The second argument passed to the xToken() callback ("tflags") should |
11374 | ** normally be set to 0. The exception is if the tokenizer supports |
11375 | ** synonyms. In this case see the discussion below for details. |
11376 | ** |
11377 | ** FTS5 assumes the xToken() callback is invoked for each token in the |
11378 | ** order that they occur within the input text. |
11379 | ** |
11380 | ** If an xToken() callback returns any value other than SQLITE_OK, then |
11381 | ** the tokenization should be abandoned and the xTokenize() method should |
11382 | ** immediately return a copy of the xToken() return value. Or, if the |
11383 | ** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally, |
11384 | ** if an error occurs with the xTokenize() implementation itself, it |
11385 | ** may abandon the tokenization and return any error code other than |
11386 | ** SQLITE_OK or SQLITE_DONE. |
11387 | ** |
11388 | ** SYNONYM SUPPORT |
11389 | ** |
11390 | ** Custom tokenizers may also support synonyms. Consider a case in which a |
11391 | ** user wishes to query for a phrase such as "first place". Using the |
11392 | ** built-in tokenizers, the FTS5 query 'first + place' will match instances |
11393 | ** of "first place" within the document set, but not alternative forms |
11394 | ** such as "1st place". In some applications, it would be better to match |
11395 | ** all instances of "first place" or "1st place" regardless of which form |
11396 | ** the user specified in the MATCH query text. |
11397 | ** |
11398 | ** There are several ways to approach this in FTS5: |
11399 | ** |
11400 | ** <ol><li> By mapping all synonyms to a single token. In this case, the |
11401 | ** In the above example, this means that the tokenizer returns the |
11402 | ** same token for inputs "first" and "1st". Say that token is in |
11403 | ** fact "first", so that when the user inserts the document "I won |
11404 | ** 1st place" entries are added to the index for tokens "i", "won", |
11405 | ** "first" and "place". If the user then queries for '1st + place', |
11406 | ** the tokenizer substitutes "first" for "1st" and the query works |
11407 | ** as expected. |
11408 | ** |
11409 | ** <li> By adding multiple synonyms for a single term to the FTS index. |
11410 | ** In this case, when tokenizing query text, the tokenizer may |
11411 | ** provide multiple synonyms for a single term within the document. |
11412 | ** FTS5 then queries the index for each synonym individually. For |
11413 | ** example, faced with the query: |
11414 | ** |
11415 | ** <codeblock> |
11416 | ** ... MATCH 'first place'</codeblock> |
11417 | ** |
11418 | ** the tokenizer offers both "1st" and "first" as synonyms for the |
11419 | ** first token in the MATCH query and FTS5 effectively runs a query |
11420 | ** similar to: |
11421 | ** |
11422 | ** <codeblock> |
11423 | ** ... MATCH '(first OR 1st) place'</codeblock> |
11424 | ** |
11425 | ** except that, for the purposes of auxiliary functions, the query |
11426 | ** still appears to contain just two phrases - "(first OR 1st)" |
11427 | ** being treated as a single phrase. |
11428 | ** |
11429 | ** <li> By adding multiple synonyms for a single term to the FTS index. |
11430 | ** Using this method, when tokenizing document text, the tokenizer |
11431 | ** provides multiple synonyms for each token. So that when a |
11432 | ** document such as "I won first place" is tokenized, entries are |
11433 | ** added to the FTS index for "i", "won", "first", "1st" and |
11434 | ** "place". |
11435 | ** |
11436 | ** This way, even if the tokenizer does not provide synonyms |
11437 | ** when tokenizing query text (it should not - to do would be |
11438 | ** inefficient), it doesn't matter if the user queries for |
11439 | ** 'first + place' or '1st + place', as there are entries in the |
11440 | ** FTS index corresponding to both forms of the first token. |
11441 | ** </ol> |
11442 | ** |
11443 | ** Whether it is parsing document or query text, any call to xToken that |
11444 | ** specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit |
11445 | ** is considered to supply a synonym for the previous token. For example, |
11446 | ** when parsing the document "I won first place", a tokenizer that supports |
11447 | ** synonyms would call xToken() 5 times, as follows: |
11448 | ** |
11449 | ** <codeblock> |
11450 | ** xToken(pCtx, 0, "i", 1, 0, 1); |
11451 | ** xToken(pCtx, 0, "won", 3, 2, 5); |
11452 | ** xToken(pCtx, 0, "first", 5, 6, 11); |
11453 | ** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11); |
11454 | ** xToken(pCtx, 0, "place", 5, 12, 17); |
11455 | **</codeblock> |
11456 | ** |
11457 | ** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time |
11458 | ** xToken() is called. Multiple synonyms may be specified for a single token |
11459 | ** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence. |
11460 | ** There is no limit to the number of synonyms that may be provided for a |
11461 | ** single token. |
11462 | ** |
11463 | ** In many cases, method (1) above is the best approach. It does not add |
11464 | ** extra data to the FTS index or require FTS5 to query for multiple terms, |
11465 | ** so it is efficient in terms of disk space and query speed. However, it |
11466 | ** does not support prefix queries very well. If, as suggested above, the |
11467 | ** token "first" is substituted for "1st" by the tokenizer, then the query: |
11468 | ** |
11469 | ** <codeblock> |
11470 | ** ... MATCH '1s*'</codeblock> |
11471 | ** |
11472 | ** will not match documents that contain the token "1st" (as the tokenizer |
11473 | ** will probably not map "1s" to any prefix of "first"). |
11474 | ** |
11475 | ** For full prefix support, method (3) may be preferred. In this case, |
11476 | ** because the index contains entries for both "first" and "1st", prefix |
11477 | ** queries such as 'fi*' or '1s*' will match correctly. However, because |
11478 | ** extra entries are added to the FTS index, this method uses more space |
11479 | ** within the database. |
11480 | ** |
11481 | ** Method (2) offers a midpoint between (1) and (3). Using this method, |
11482 | ** a query such as '1s*' will match documents that contain the literal |
11483 | ** token "1st", but not "first" (assuming the tokenizer is not able to |
11484 | ** provide synonyms for prefixes). However, a non-prefix query like '1st' |
11485 | ** will match against "1st" and "first". This method does not require |
11486 | ** extra disk space, as no extra entries are added to the FTS index. |
11487 | ** On the other hand, it may require more CPU cycles to run MATCH queries, |
11488 | ** as separate queries of the FTS index are required for each synonym. |
11489 | ** |
11490 | ** When using methods (2) or (3), it is important that the tokenizer only |
11491 | ** provide synonyms when tokenizing document text (method (2)) or query |
11492 | ** text (method (3)), not both. Doing so will not cause any errors, but is |
11493 | ** inefficient. |
11494 | */ |
11495 | typedef struct Fts5Tokenizer Fts5Tokenizer; |
11496 | typedef struct fts5_tokenizer fts5_tokenizer; |
11497 | struct fts5_tokenizer { |
11498 | int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut); |
11499 | void (*xDelete)(Fts5Tokenizer*); |
11500 | int (*xTokenize)(Fts5Tokenizer*, |
11501 | void *pCtx, |
11502 | int flags, /* Mask of FTS5_TOKENIZE_* flags */ |
11503 | const char *pText, int nText, |
11504 | int (*xToken)( |
11505 | void *pCtx, /* Copy of 2nd argument to xTokenize() */ |
11506 | int tflags, /* Mask of FTS5_TOKEN_* flags */ |
11507 | const char *pToken, /* Pointer to buffer containing token */ |
11508 | int nToken, /* Size of token in bytes */ |
11509 | int iStart, /* Byte offset of token within input text */ |
11510 | int iEnd /* Byte offset of end of token within input text */ |
11511 | ) |
11512 | ); |
11513 | }; |
11514 | |
11515 | /* Flags that may be passed as the third argument to xTokenize() */ |
11516 | #define FTS5_TOKENIZE_QUERY 0x0001 |
11517 | #define FTS5_TOKENIZE_PREFIX 0x0002 |
11518 | #define FTS5_TOKENIZE_DOCUMENT 0x0004 |
11519 | #define FTS5_TOKENIZE_AUX 0x0008 |
11520 | |
11521 | /* Flags that may be passed by the tokenizer implementation back to FTS5 |
11522 | ** as the third argument to the supplied xToken callback. */ |
11523 | #define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */ |
11524 | |
11525 | /* |
11526 | ** END OF CUSTOM TOKENIZERS |
11527 | *************************************************************************/ |
11528 | |
11529 | /************************************************************************* |
11530 | ** FTS5 EXTENSION REGISTRATION API |
11531 | */ |
11532 | typedef struct fts5_api fts5_api; |
11533 | struct fts5_api { |
11534 | int iVersion; /* Currently always set to 2 */ |
11535 | |
11536 | /* Create a new tokenizer */ |
11537 | int (*xCreateTokenizer)( |
11538 | fts5_api *pApi, |
11539 | const char *zName, |
11540 | void *pContext, |
11541 | fts5_tokenizer *pTokenizer, |
11542 | void (*xDestroy)(void*) |
11543 | ); |
11544 | |
11545 | /* Find an existing tokenizer */ |
11546 | int (*xFindTokenizer)( |
11547 | fts5_api *pApi, |
11548 | const char *zName, |
11549 | void **ppContext, |
11550 | fts5_tokenizer *pTokenizer |
11551 | ); |
11552 | |
11553 | /* Create a new auxiliary function */ |
11554 | int (*xCreateFunction)( |
11555 | fts5_api *pApi, |
11556 | const char *zName, |
11557 | void *pContext, |
11558 | fts5_extension_function xFunction, |
11559 | void (*xDestroy)(void*) |
11560 | ); |
11561 | }; |
11562 | |
11563 | /* |
11564 | ** END OF REGISTRATION API |
11565 | *************************************************************************/ |
11566 | |
11567 | #ifdef __cplusplus |
11568 | } /* end of the 'extern "C"' block */ |
11569 | #endif |
11570 | |
11571 | #endif /* _FTS5_H */ |
11572 | |
11573 | /******** End of fts5.h *********/ |
11574 | |