diff options
Diffstat (limited to 'sql/handler.h')
| -rw-r--r-- | sql/handler.h | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/sql/handler.h b/sql/handler.h index 35d27599d9d..7c6f182bb97 100644 --- a/sql/handler.h +++ b/sql/handler.h @@ -354,7 +354,8 @@ enum legacy_db_type DB_TYPE_BINLOG=21, DB_TYPE_PBXT=23, DB_TYPE_PERFORMANCE_SCHEMA=28, - DB_TYPE_FIRST_DYNAMIC=42, + DB_TYPE_ARIA=42, + DB_TYPE_FIRST_DYNAMIC=43, DB_TYPE_DEFAULT=127 // Must be last }; /* @@ -2783,7 +2784,33 @@ public: Pops the top if condition stack, if stack is not empty. */ virtual void cond_pop() { return; }; + + /** + Push down an index condition to the handler. + + The server will use this method to push down a condition it wants + the handler to evaluate when retrieving records using a specified + index. The pushed index condition will only refer to fields from + this handler that is contained in the index (but it may also refer + to fields in other handlers). Before the handler evaluates the + condition it must read the content of the index entry into the + record buffer. + + The handler is free to decide if and how much of the condition it + will take responsibility for evaluating. Based on this evaluation + it should return the part of the condition it will not evaluate. + If it decides to evaluate the entire condition it should return + NULL. If it decides not to evaluate any part of the condition it + should return a pointer to the same condition as given as argument. + + @param keyno the index number to evaluate the condition on + @param idx_cond the condition to be evaluated by the handler + + @return The part of the pushed condition that the handler decides + not to evaluate + */ virtual Item *idx_cond_push(uint keyno, Item* idx_cond) { return idx_cond; } + /** Reset information about pushed index conditions */ virtual void cancel_pushed_idx_cond() { |