diff options
Diffstat (limited to 'sql/sql_const.h')
| -rw-r--r-- | sql/sql_const.h | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/sql/sql_const.h b/sql/sql_const.h index 0cd214d8bc7..1d6549f777f 100644 --- a/sql/sql_const.h +++ b/sql/sql_const.h @@ -33,7 +33,17 @@ #define MAX_SYS_VAR_LENGTH 32 #define MAX_KEY MAX_INDEXES /* Max used keys */ #define MAX_REF_PARTS 32 /* Max parts used as ref */ -#define MAX_KEY_LENGTH 3072 /* max possible key */ + +/* + Maximum length of the data part of an index lookup key. + + The "data part" is defined as the value itself, not including the + NULL-indicator bytes or varchar length bytes ("the Extras"). We need this + value because there was a bug where length of the Extras were not counted. + + You probably need MAX_KEY_LENGTH, not this constant. +*/ +#define MAX_DATA_LENGTH_FOR_KEY 3072 #if SIZEOF_OFF_T > 4 #define MAX_REFLENGTH 8 /* Max length for record ref */ #else |