diff options
Diffstat (limited to 'sql/sql_const.h')
| -rw-r--r-- | sql/sql_const.h | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/sql/sql_const.h b/sql/sql_const.h index dca66628ddb..d08a8f18308 100644 --- a/sql/sql_const.h +++ b/sql/sql_const.h @@ -30,7 +30,7 @@ #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 16 /* Max parts used as ref */ +#define MAX_REF_PARTS 32 /* Max parts used as ref */ #define MAX_KEY_LENGTH 3072 /* max possible key */ #if SIZEOF_OFF_T > 4 #define MAX_REFLENGTH 8 /* Max length for record ref */ @@ -176,11 +176,11 @@ 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)0.5) +#define DISK_SEEK_BASE_COST ((double)0.9) #define BLOCKS_IN_AVG_SEEK 128 -#define DISK_SEEK_PROP_COST ((double)0.5/BLOCKS_IN_AVG_SEEK) +#define DISK_SEEK_PROP_COST ((double)0.1/BLOCKS_IN_AVG_SEEK) /** @@ -190,6 +190,12 @@ */ #define MATCHING_ROWS_IN_OTHER_TABLE 10 +/* + Subquery materialization-related constants +*/ +#define HEAP_TEMPTABLE_LOOKUP_COST 0.05 +#define DISK_TEMPTABLE_LOOKUP_COST 1.0 + #define MY_CHARSET_BIN_MB_MAXLEN 1 /** Don't pack string keys shorter than this (if PACK_KEYS=1 isn't used). */ |