sql_const.h

Go to the documentation of this file.

/* Copyright (c) 2006, 2011, Oracle and/or its affiliates. All rights reserved.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA */

#ifndef SQL_CONST_INCLUDED
#define SQL_CONST_INCLUDED

#define LIBLEN FN_REFLEN-FN_LEN                 /* Max l{ngd p} dev */
/* extra 4+4 bytes for slave tmp tables */
#define MAX_DBKEY_LENGTH (NAME_LEN*2+1+1+4+4)
#define MAX_ALIAS_NAME 256
#define MAX_FIELD_NAME 34                       /* Max colum name length +2 */
#define MAX_SYS_VAR_LENGTH 32
#define MAX_KEY MAX_INDEXES                     /* Max used keys */
#define MAX_REF_PARTS 16U                       /* Max parts used as ref */
#define MAX_KEY_LENGTH 3072U                    /* max possible key */
#if SIZEOF_OFF_T > 4
#define MAX_REFLENGTH 8                         /* Max length for record ref */
#else
#define MAX_REFLENGTH 4                         /* Max length for record ref */
#endif
#define MAX_HOSTNAME  61                        /* len+1 in mysql.user */

#define MAX_MBWIDTH             3               /* Max multibyte sequence */
#define MAX_FIELD_CHARLENGTH    255
#define MAX_FIELD_VARCHARLENGTH 65535
#define MAX_FIELD_BLOBLENGTH UINT_MAX32     /* cf field_blob::get_length() */
#define CONVERT_IF_BIGGER_TO_BLOB 512           /* Used for CREATE ... SELECT */

/* Max column width +1 */
#define MAX_FIELD_WIDTH         (MAX_FIELD_CHARLENGTH*MAX_MBWIDTH+1)

#define MAX_BIT_FIELD_LENGTH    64      /* Max length in bits for bit fields */

#define MAX_DATE_WIDTH          10      /* YYYY-MM-DD */
#define MAX_TIME_WIDTH          10      /* -838:59:59 */
#define MAX_TIME_FULL_WIDTH     23      /* -DDDDDD HH:MM:SS.###### */
#define MAX_DATETIME_FULL_WIDTH 29      /* YYYY-MM-DD HH:MM:SS.###### AM */
#define MAX_DATETIME_WIDTH      19      /* YYYY-MM-DD HH:MM:SS */
#define MAX_DATETIME_COMPRESSED_WIDTH 14  /* YYYYMMDDHHMMSS */

#define DATE_INT_DIGITS       8         /* YYYYMMDD       */
#define TIME_INT_DIGITS       7         /* hhhmmss        */
#define DATETIME_INT_DIGITS  14         /* YYYYMMDDhhmmss */

#define MAX_TABLES      (sizeof(table_map)*8-3) /* Max tables in join */
#define PARAM_TABLE_BIT (((table_map) 1) << (sizeof(table_map)*8-3))
#define OUTER_REF_TABLE_BIT     (((table_map) 1) << (sizeof(table_map)*8-2))
#define RAND_TABLE_BIT  (((table_map) 1) << (sizeof(table_map)*8-1))
#define PSEUDO_TABLE_BITS (PARAM_TABLE_BIT | OUTER_REF_TABLE_BIT | \
                           RAND_TABLE_BIT)
#define MAX_FIELDS      4096                    /* Limit in the .frm file */
#define MAX_PARTITIONS  8192

#define MAX_SELECT_NESTING (sizeof(nesting_map)*8-1)

#define DEFAULT_SORT_MEMORY (256U* 1024U)
#define MIN_SORT_MEMORY     (32U * 1024U)

/* Some portable defines */

#define STRING_BUFFER_USUAL_SIZE 80

/* Memory allocated when parsing a statement / saving a statement */
#define MEM_ROOT_BLOCK_SIZE       8192
#define MEM_ROOT_PREALLOC         8192
#define TRANS_MEM_ROOT_BLOCK_SIZE 4096
#define TRANS_MEM_ROOT_PREALLOC   4096

#define DEFAULT_ERROR_COUNT     64
#define EXTRA_RECORDS   10                      /* Extra records in sort */
#define SCROLL_EXTRA    5                       /* Extra scroll-rows. */
#define FIELD_NAME_USED ((uint) 32768)          /* Bit set if fieldname used */
#define FORM_NAME_USED  ((uint) 16384)          /* Bit set if formname used */
#define FIELD_NR_MASK   16383                   /* To get fieldnumber */
#define FERR            -1                      /* Error from my_functions */
#define CREATE_MODE     0                       /* Default mode on new files */
#define NAMES_SEP_CHAR  '\377'                  /* Char to sep. names */

#define READ_RECORD_BUFFER      (uint) (IO_SIZE*8) /* Pointer_buffer_size */
#define DISK_BUFFER_SIZE        (uint) (IO_SIZE*16) /* Size of diskbuffer */

#define FRM_VER_TRUE_VARCHAR (FRM_VER+4) /* 10 */

/***************************************************************************
  Configuration parameters
****************************************************************************/

#define ACL_CACHE_SIZE          256
#define MAX_PASSWORD_LENGTH     32
#define HOST_CACHE_SIZE         128
#define MAX_ACCEPT_RETRY        10      // Test accept this many times
#define MAX_FIELDS_BEFORE_HASH  32
#define USER_VARS_HASH_SIZE     16
#define TABLE_OPEN_CACHE_MIN    400
#define TABLE_OPEN_CACHE_DEFAULT 2000
#define TABLE_DEF_CACHE_DEFAULT 400

#define MAX_CONNECTIONS_DEFAULT 151

#define TABLE_DEF_CACHE_MIN     400

/*
  Stack reservation.
  Feel free to raise this by the smallest amount you can to get the
  "execution_constants" test to pass.
*/
#define STACK_MIN_SIZE          16000   // Abort if less stack during eval.

#define STACK_MIN_SIZE_FOR_OPEN 1024*80
#define STACK_BUFF_ALLOC        352     
#ifndef MYSQLD_NET_RETRY_COUNT
#define MYSQLD_NET_RETRY_COUNT  10      
#endif

#define QUERY_ALLOC_BLOCK_SIZE          8192
#define QUERY_ALLOC_PREALLOC_SIZE       8192
#define TRANS_ALLOC_BLOCK_SIZE          4096
#define TRANS_ALLOC_PREALLOC_SIZE       4096
#define RANGE_ALLOC_BLOCK_SIZE          4096
#define ACL_ALLOC_BLOCK_SIZE            1024
#define UDF_ALLOC_BLOCK_SIZE            1024
#define TABLE_ALLOC_BLOCK_SIZE          1024
#define WARN_ALLOC_BLOCK_SIZE           2048
#define WARN_ALLOC_PREALLOC_SIZE        1024

/*
  The following parameters is to decide when to use an extra cache to
  optimise seeks when reading a big table in sorted order
*/
#define MIN_FILE_LENGTH_TO_USE_ROW_CACHE (10L*1024*1024)
#define MIN_ROWS_TO_USE_TABLE_CACHE      100
#define MIN_ROWS_TO_USE_BULK_INSERT      100

#define ROW_EVALUATE_COST  0.20

#define ROWID_COMPARE_COST 0.10  // Half the cost of a general row comparison

/*
  For sequential disk seeks the cost formula is:
    DISK_SEEK_BASE_COST + DISK_SEEK_PROP_COST * #blocks_to_skip  
  
  The cost of average seek 
    DISK_SEEK_BASE_COST + DISK_SEEK_PROP_COST*BLOCKS_IN_AVG_SEEK =1.0.
*/
#define DISK_SEEK_BASE_COST ((double)0.9)

#define BLOCKS_IN_AVG_SEEK  128

#define DISK_SEEK_PROP_COST ((double)0.1/BLOCKS_IN_AVG_SEEK)


#define MATCHING_ROWS_IN_OTHER_TABLE 10

/*
  Constants related to the use of temporary tables in query execution.
  Lookup and write operations are currently assumed to be equally costly
  (concerns HEAP_TEMPTABLE_ROW_COST and DISK_TEMPTABLE_ROW_COST).
*/
/*
  Creating a Heap temporary table is by benchmark found to be as costly as
  writing 10 rows into the table.
*/
#define HEAP_TEMPTABLE_CREATE_COST    2.0
/*
  Writing a row to or reading a row from a Heap temporary table is equivalent
  to evaluating a row in the join engine.
*/
#define HEAP_TEMPTABLE_ROW_COST       0.2
/*
  Creating a MyISAM table is 20 times slower than creating a Heap table.
*/
#define DISK_TEMPTABLE_CREATE_COST   40.0
/*
  Generating MyIsam rows sequentially is 2 times slower than generating
  Heap rows, when number of rows is greater than 1000. However, we do not have
  benchmarks for very large tables, so setting this factor conservatively to
  be 5 times slower (ie the cost is 1.0).
*/
#define DISK_TEMPTABLE_ROW_COST       1.0

#define MY_CHARSET_BIN_MB_MAXLEN 1

#define KEY_DEFAULT_PACK_LENGTH 8

#define PROCESS_LIST_WIDTH 100
/* Characters shown for the command in 'information_schema.processlist' */
#define PROCESS_LIST_INFO_WIDTH 65535

#define PRECISION_FOR_DOUBLE 53
#define PRECISION_FOR_FLOAT  24

/* -[digits].E+## */
#define MAX_FLOAT_STR_LENGTH (FLT_DIG + 6)
/* -[digits].E+### */
#define MAX_DOUBLE_STR_LENGTH (DBL_DIG + 7)

/*
  Default time to wait before aborting a new client connection
  that does not respond to "initial server greeting" timely
*/
#define CONNECT_TIMEOUT         10

/* The following can also be changed from the command line */
#define DEFAULT_CONCURRENCY     10
#define DELAYED_LIMIT           100             
#define DELAYED_QUEUE_SIZE      1000
#define DELAYED_WAIT_TIMEOUT    5*60            
#define LONG_TIMEOUT ((ulong) 3600L*24L*365L)

#define MAX_TIME_ZONE_NAME_LENGTH       (NAME_LEN + 1)

#if defined(__WIN__)
#define INTERRUPT_PRIOR -2
#define CONNECT_PRIOR   -1
#define WAIT_PRIOR      0
#define QUERY_PRIOR     2
#else
#define INTERRUPT_PRIOR 10
#define CONNECT_PRIOR   9
#define WAIT_PRIOR      8
#define QUERY_PRIOR     6
#endif /* __WIN92__ */

#endif /* SQL_CONST_INCLUDED */