1/* Copyright (c) 2006, 2010, Oracle and/or its affiliates. All rights reserved.
2
3 This program is free software; you can redistribute it and/or modify
4 it under the terms of the GNU General Public License as published by
5 the Free Software Foundation; version 2 of the License.
6
7 This program is distributed in the hope that it will be useful,
8 but WITHOUT ANY WARRANTY; without even the implied warranty of
9 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 GNU General Public License for more details.
11
12 You should have received a copy of the GNU General Public License
13 along with this program; if not, write to the Free Software
14 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
15
16/**
17 @file
18 File containing constants that can be used throughout the server.
19
20 @note This file shall not contain or include any declarations of any kinds.
21*/
22
23#ifndef SQL_CONST_INCLUDED
24#define SQL_CONST_INCLUDED
25
26#include <mysql_version.h>
27
28#define LIBLEN FN_REFLEN-FN_LEN /* Max l{ngd p} dev */
29/* extra 4+4 bytes for slave tmp tables */
30#define MAX_DBKEY_LENGTH (NAME_LEN*2+1+1+4+4)
31#define MAX_ALIAS_NAME 256
32#define MAX_FIELD_NAME 34 /* Max colum name length +2 */
33#define MAX_SYS_VAR_LENGTH 32
34#define MAX_KEY MAX_INDEXES /* Max used keys */
35#define MAX_REF_PARTS 32 /* Max parts used as ref */
36#define MAX_KEY_LENGTH 3072 /* max possible key */
37#if SIZEOF_OFF_T > 4
38#define MAX_REFLENGTH 8 /* Max length for record ref */
39#else
40#define MAX_REFLENGTH 4 /* Max length for record ref */
41#endif
42#define MAX_HOSTNAME 61 /* len+1 in mysql.user */
43#define MAX_CONNECTION_NAME NAME_LEN
44
45#define MAX_MBWIDTH 3 /* Max multibyte sequence */
46#define MAX_FILENAME_MBWIDTH 5
47#define MAX_FIELD_CHARLENGTH 255
48/*
49 In MAX_FIELD_VARCHARLENGTH we reserve extra bytes for the overhead:
50 - 2 bytes for the length
51 - 1 byte for NULL bits
52 to avoid the "Row size too large" error for these three corner definitions:
53 CREATE TABLE t1 (c VARBINARY(65533));
54 CREATE TABLE t1 (c VARBINARY(65534));
55 CREATE TABLE t1 (c VARBINARY(65535));
56 Like VARCHAR(65536), they will be converted to BLOB automatically
57 in non-sctict mode.
58*/
59#define MAX_FIELD_VARCHARLENGTH (65535-2-1)
60#define MAX_FIELD_BLOBLENGTH UINT_MAX32 /* cf field_blob::get_length() */
61#define CONVERT_IF_BIGGER_TO_BLOB 512 /* Threshold *in characters* */
62
63/* Max column width +1 */
64#define MAX_FIELD_WIDTH (MAX_FIELD_CHARLENGTH*MAX_MBWIDTH+1)
65
66#define MAX_BIT_FIELD_LENGTH 64 /* Max length in bits for bit fields */
67
68#define MAX_DATE_WIDTH 10 /* YYYY-MM-DD */
69#define MIN_TIME_WIDTH 10 /* -HHH:MM:SS */
70#define MAX_TIME_WIDTH 16 /* -DDDDDD HH:MM:SS */
71#define MAX_TIME_FULL_WIDTH 23 /* -DDDDDD HH:MM:SS.###### */
72#define MAX_DATETIME_FULL_WIDTH 26 /* YYYY-MM-DD HH:MM:SS.###### */
73#define MAX_DATETIME_WIDTH 19 /* YYYY-MM-DD HH:MM:SS */
74#define MAX_DATETIME_COMPRESSED_WIDTH 14 /* YYYYMMDDHHMMSS */
75#define MAX_DATETIME_PRECISION 6
76
77#define MAX_TABLES (sizeof(table_map)*8-3) /* Max tables in join */
78#define PARAM_TABLE_BIT (((table_map) 1) << (sizeof(table_map)*8-3))
79#define OUTER_REF_TABLE_BIT (((table_map) 1) << (sizeof(table_map)*8-2))
80#define RAND_TABLE_BIT (((table_map) 1) << (sizeof(table_map)*8-1))
81#define PSEUDO_TABLE_BITS (PARAM_TABLE_BIT | OUTER_REF_TABLE_BIT | \
82 RAND_TABLE_BIT)
83#define CONNECT_STRING_MAXLEN 65535 /* stored in 2 bytes in .frm */
84#define MAX_FIELDS 4096 /* Limit in the .frm file */
85#define MAX_PARTITIONS 8192
86
87#define MAX_SELECT_NESTING (sizeof(nesting_map)*8-1)
88
89#define MAX_SORT_MEMORY 2048*1024
90#define MIN_SORT_MEMORY 1024
91
92/* Some portable defines */
93
94#define STRING_BUFFER_USUAL_SIZE 80
95
96/* Memory allocated when parsing a statement / saving a statement */
97#define MEM_ROOT_BLOCK_SIZE 8192
98#define MEM_ROOT_PREALLOC 8192
99#define TRANS_MEM_ROOT_BLOCK_SIZE 4096
100#define TRANS_MEM_ROOT_PREALLOC 4096
101
102#define DEFAULT_ERROR_COUNT 64
103#define EXTRA_RECORDS 10 /* Extra records in sort */
104#define SCROLL_EXTRA 5 /* Extra scroll-rows. */
105#define FIELD_NAME_USED ((uint) 32768) /* Bit set if fieldname used */
106#define FORM_NAME_USED ((uint) 16384) /* Bit set if formname used */
107#define FIELD_NR_MASK 16383 /* To get fieldnumber */
108#define FERR -1 /* Error from my_functions */
109#define CREATE_MODE 0 /* Default mode on new files */
110#define NAMES_SEP_CHAR 255 /* Char to sep. names */
111
112#define READ_RECORD_BUFFER (uint) (IO_SIZE*8) /* Pointer_buffer_size */
113#define DISK_BUFFER_SIZE (uint) (IO_SIZE*16) /* Size of diskbuffer */
114
115#define FRM_VER_TRUE_VARCHAR (FRM_VER+4) /* 10 */
116#define FRM_VER_EXPRESSSIONS (FRM_VER+5) /* 11 */
117#define FRM_VER_CURRENT FRM_VER_EXPRESSSIONS
118
119/***************************************************************************
120 Configuration parameters
121****************************************************************************/
122
123#define ACL_CACHE_SIZE 256
124#define MAX_PASSWORD_LENGTH 32
125#define HOST_CACHE_SIZE 128
126#define MAX_ACCEPT_RETRY 10 // Test accept this many times
127#define MAX_FIELDS_BEFORE_HASH 32
128#define USER_VARS_HASH_SIZE 16
129#define SEQUENCES_HASH_SIZE 16
130#define TABLE_OPEN_CACHE_MIN 200
131#define TABLE_OPEN_CACHE_DEFAULT 2000
132#define TABLE_DEF_CACHE_DEFAULT 400
133/**
134 We must have room for at least 400 table definitions in the table
135 cache, since otherwise there is no chance prepared
136 statements that use these many tables can work.
137 Prepared statements use table definition cache ids (table_map_id)
138 as table version identifiers. If the table definition
139 cache size is less than the number of tables used in a statement,
140 the contents of the table definition cache is guaranteed to rotate
141 between a prepare and execute. This leads to stable validation
142 errors. In future we shall use more stable version identifiers,
143 for now the only solution is to ensure that the table definition
144 cache can contain at least all tables of a given statement.
145*/
146#define TABLE_DEF_CACHE_MIN 400
147
148/**
149 Maximum number of connections default value.
150 151 is larger than Apache's default max children,
151 to avoid "too many connections" error in a common setup.
152*/
153#define MAX_CONNECTIONS_DEFAULT 151
154
155/*
156 Stack reservation.
157 Feel free to raise this by the smallest amount you can to get the
158 "execution_constants" test to pass.
159*/
160#define STACK_MIN_SIZE 16000 // Abort if less stack during eval.
161
162#define STACK_MIN_SIZE_FOR_OPEN (1024*80)
163#define STACK_BUFF_ALLOC 352 ///< For stack overrun checks
164#ifndef MYSQLD_NET_RETRY_COUNT
165#define MYSQLD_NET_RETRY_COUNT 10 ///< Abort read after this many int.
166#endif
167
168#define QUERY_ALLOC_BLOCK_SIZE 16384
169#define QUERY_ALLOC_PREALLOC_SIZE 24576
170#define TRANS_ALLOC_BLOCK_SIZE 8192
171#define TRANS_ALLOC_PREALLOC_SIZE 4096
172#define RANGE_ALLOC_BLOCK_SIZE 4096
173#define ACL_ALLOC_BLOCK_SIZE 1024
174#define UDF_ALLOC_BLOCK_SIZE 1024
175#define TABLE_ALLOC_BLOCK_SIZE 1024
176#define WARN_ALLOC_BLOCK_SIZE 2048
177#define WARN_ALLOC_PREALLOC_SIZE 1024
178/*
179 Note that if we are using 32K or less, then TCmalloc will use a local
180 heap without locks!
181*/
182#define SHOW_ALLOC_BLOCK_SIZE (32768-MALLOC_OVERHEAD)
183
184/*
185 The following parameters is to decide when to use an extra cache to
186 optimise seeks when reading a big table in sorted order
187*/
188#define MIN_FILE_LENGTH_TO_USE_ROW_CACHE (10L*1024*1024)
189#define MIN_ROWS_TO_USE_TABLE_CACHE 100
190#define MIN_ROWS_TO_USE_BULK_INSERT 100
191
192/**
193 The following is used to decide if MySQL should use table scanning
194 instead of reading with keys. The number says how many evaluation of the
195 WHERE clause is comparable to reading one extra row from a table.
196*/
197#define TIME_FOR_COMPARE 5 // 5 compares == one read
198
199/**
200 Number of comparisons of table rowids equivalent to reading one row from a
201 table.
202*/
203#define TIME_FOR_COMPARE_ROWID (TIME_FOR_COMPARE*100)
204
205/* cost1 is better that cost2 only if cost1 + COST_EPS < cost2 */
206#define COST_EPS 0.001
207
208/*
209 For sequential disk seeks the cost formula is:
210 DISK_SEEK_BASE_COST + DISK_SEEK_PROP_COST * #blocks_to_skip
211
212 The cost of average seek
213 DISK_SEEK_BASE_COST + DISK_SEEK_PROP_COST*BLOCKS_IN_AVG_SEEK =1.0.
214*/
215#define DISK_SEEK_BASE_COST ((double)0.9)
216
217#define BLOCKS_IN_AVG_SEEK 128
218
219#define DISK_SEEK_PROP_COST ((double)0.1/BLOCKS_IN_AVG_SEEK)
220
221
222/**
223 Number of rows in a reference table when refereed through a not unique key.
224 This value is only used when we don't know anything about the key
225 distribution.
226*/
227#define MATCHING_ROWS_IN_OTHER_TABLE 10
228
229/*
230 Subquery materialization-related constants
231*/
232#define HEAP_TEMPTABLE_LOOKUP_COST 0.05
233#define DISK_TEMPTABLE_LOOKUP_COST 1.0
234#define SORT_INDEX_CMP_COST 0.02
235
236#define MY_CHARSET_BIN_MB_MAXLEN 1
237
238/** Don't pack string keys shorter than this (if PACK_KEYS=1 isn't used). */
239#define KEY_DEFAULT_PACK_LENGTH 8
240
241/** Characters shown for the command in 'show processlist'. */
242#define PROCESS_LIST_WIDTH 100
243/* Characters shown for the command in 'information_schema.processlist' */
244#define PROCESS_LIST_INFO_WIDTH 65535
245
246#define PRECISION_FOR_DOUBLE 53
247#define PRECISION_FOR_FLOAT 24
248
249/* -[digits].E+## */
250#define MAX_FLOAT_STR_LENGTH (FLT_DIG + 6)
251/* -[digits].E+### */
252#define MAX_DOUBLE_STR_LENGTH (DBL_DIG + 7)
253
254/*
255 Default time to wait before aborting a new client connection
256 that does not respond to "initial server greeting" timely
257*/
258#define CONNECT_TIMEOUT 10
259 /* Wait 5 minutes before removing thread from thread cache */
260#define THREAD_CACHE_TIMEOUT 5*60
261
262/* The following can also be changed from the command line */
263#define DEFAULT_CONCURRENCY 10
264#define DELAYED_LIMIT 100 /**< pause after xxx inserts */
265#define DELAYED_QUEUE_SIZE 1000
266#define DELAYED_WAIT_TIMEOUT (5*60) /**< Wait for delayed insert */
267#define MAX_CONNECT_ERRORS 100 ///< errors before disabling host
268
269#define LONG_TIMEOUT ((ulong) 3600L*24L*365L)
270
271/**
272 Maximum length of time zone name that we support (Time zone name is
273 char(64) in db). mysqlbinlog needs it.
274*/
275#define MAX_TIME_ZONE_NAME_LENGTH (NAME_LEN + 1)
276
277#if defined(__WIN__)
278
279#define INTERRUPT_PRIOR -2
280#define CONNECT_PRIOR -1
281#define WAIT_PRIOR 0
282#define QUERY_PRIOR 2
283#else
284#define INTERRUPT_PRIOR 10
285#define CONNECT_PRIOR 9
286#define WAIT_PRIOR 8
287#define QUERY_PRIOR 6
288#endif /* __WIN92__ */
289
290#endif /* SQL_CONST_INCLUDED */
291