diff options
Diffstat (limited to 'sql/opt_range.cc')
| -rw-r--r-- | sql/opt_range.cc | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/sql/opt_range.cc b/sql/opt_range.cc index 628b07631c1..733203b3160 100644 --- a/sql/opt_range.cc +++ b/sql/opt_range.cc @@ -219,6 +219,8 @@ public: } inline void merge_flags(SEL_ARG *arg) { maybe_flag|=arg->maybe_flag; } inline void maybe_smaller() { maybe_flag=1; } + /* Return true iff it's a single-point null interval */ + inline bool is_null_interval() { return maybe_null && max_value[0] == 1; } inline int cmp_min_to_min(SEL_ARG* arg) { return sel_cmp(field,min_value, arg->min_value, min_flag, arg->min_flag); @@ -560,6 +562,7 @@ public: bool is_ror_scan; /* Number of ranges in the last checked tree->key */ uint n_ranges; + uint8 first_null_comp; /* first null component if any, 0 - otherwise */ }; class TABLE_READ_PLAN; @@ -7016,6 +7019,7 @@ check_quick_select(PARAM *param,uint idx,SEL_ARG *tree, bool update_tbl_stats) DBUG_ENTER("check_quick_select"); param->is_ror_scan= FALSE; + param->first_null_comp= 0; if (!tree) DBUG_RETURN(HA_POS_ERROR); // Can't use it @@ -7116,6 +7120,7 @@ check_quick_keys(PARAM *param,uint idx,SEL_ARG *key_tree, ha_rows records=0, tmp; uint tmp_min_flag, tmp_max_flag, keynr, min_key_length, max_key_length; char *tmp_min_key, *tmp_max_key; + uint8 save_first_null_comp= param->first_null_comp; param->max_key_part=max(param->max_key_part,key_tree->part); if (key_tree->left != &null_element) @@ -7153,6 +7158,9 @@ check_quick_keys(PARAM *param,uint idx,SEL_ARG *key_tree, param->is_ror_scan= FALSE; } + if (!param->first_null_comp && key_tree->is_null_interval()) + param->first_null_comp= key_tree->part+1; + if (key_tree->next_key_part && key_tree->next_key_part->part == key_tree->part+1 && key_tree->next_key_part->type == SEL_ARG::KEY_RANGE) @@ -7196,7 +7204,8 @@ check_quick_keys(PARAM *param,uint idx,SEL_ARG *key_tree, (param->table->key_info[keynr].flags & (HA_NOSAME | HA_END_SPACE_KEY)) == HA_NOSAME && min_key_length == max_key_length && - !memcmp(param->min_key,param->max_key,min_key_length)) + !memcmp(param->min_key,param->max_key,min_key_length) && + !param->first_null_comp) { tmp=1; // Max one record param->n_ranges++; @@ -7271,6 +7280,7 @@ check_quick_keys(PARAM *param,uint idx,SEL_ARG *key_tree, return tmp; records+=tmp; } + param->first_null_comp= save_first_null_comp; return records; } |