diff options
Diffstat (limited to 'sql/opt_index_cond_pushdown.cc')
| -rw-r--r-- | sql/opt_index_cond_pushdown.cc | 90 |
1 files changed, 55 insertions, 35 deletions
diff --git a/sql/opt_index_cond_pushdown.cc b/sql/opt_index_cond_pushdown.cc index cee96d88438..12a732176a5 100644 --- a/sql/opt_index_cond_pushdown.cc +++ b/sql/opt_index_cond_pushdown.cc @@ -83,15 +83,44 @@ bool uses_index_fields_only(Item *item, TABLE *tbl, uint keyno, case Item::FIELD_ITEM: { Item_field *item_field= (Item_field*)item; - if (item_field->field->table != tbl) + Field *field= item_field->field; + if (field->table != tbl) return TRUE; /* The below is probably a repetition - the first part checks the other two, but let's play it safe: */ - return item_field->field->part_of_key.is_set(keyno) && - item_field->field->type() != MYSQL_TYPE_GEOMETRY && - item_field->field->type() != MYSQL_TYPE_BLOB; + if(!field->part_of_key.is_set(keyno) || + field->type() == MYSQL_TYPE_GEOMETRY || + field->type() == MYSQL_TYPE_BLOB) + return FALSE; + KEY *key_info= tbl->key_info + keyno; + KEY_PART_INFO *key_part= key_info->key_part; + KEY_PART_INFO *key_part_end= key_part + key_info->key_parts; + for ( ; key_part < key_part_end; key_part++) + { + if (field->eq(key_part->field)) + return !(key_part->key_part_flag & HA_PART_KEY_SEG); + } + if ((tbl->file->ha_table_flags() & HA_PRIMARY_KEY_IN_READ_INDEX) && + tbl->s->primary_key != MAX_KEY && + tbl->s->primary_key != keyno) + { + key_info= tbl->key_info + tbl->s->primary_key; + key_part= key_info->key_part; + key_part_end= key_part + key_info->key_parts; + for ( ; key_part < key_part_end; key_part++) + { + /* + It does not make sense to use the fact that the engine can read in + a full field if the key if the index is built only over a part + of this field. + */ + if (field->eq(key_part->field)) + return !(key_part->key_part_flag & HA_PART_KEY_SEG); + } + } + return FALSE; } case Item::REF_ITEM: return uses_index_fields_only(item->real_item(), tbl, keyno, @@ -210,11 +239,9 @@ Item *make_cond_for_index(Item *cond, TABLE *table, uint keyno, } -Item *make_cond_remainder(Item *cond, bool exclude_index) +Item *make_cond_remainder(Item *cond, TABLE *table, uint keyno, + bool other_tbls_ok, bool exclude_index) { - if (exclude_index && cond->marker == ICP_COND_USES_INDEX_ONLY) - return 0; /* Already checked */ - if (cond->type() == Item::COND_ITEM) { table_map tbl_map= 0; @@ -228,7 +255,8 @@ Item *make_cond_remainder(Item *cond, bool exclude_index) Item *item; while ((item=li++)) { - Item *fix= make_cond_remainder(item, exclude_index); + Item *fix= make_cond_remainder(item, table, keyno, + other_tbls_ok, exclude_index); if (fix) { new_cond->argument_list()->push_back(fix); @@ -255,7 +283,8 @@ Item *make_cond_remainder(Item *cond, bool exclude_index) Item *item; while ((item=li++)) { - Item *fix= make_cond_remainder(item, FALSE); + Item *fix= make_cond_remainder(item, table, keyno, + other_tbls_ok, FALSE); if (!fix) return (COND*) 0; new_cond->argument_list()->push_back(fix); @@ -267,7 +296,14 @@ Item *make_cond_remainder(Item *cond, bool exclude_index) return new_cond; } } - return cond; + else + { + if (exclude_index && + uses_index_fields_only(cond, table, keyno, other_tbls_ok)) + return 0; + else + return cond; + } } @@ -288,30 +324,13 @@ void push_index_cond(JOIN_TAB *tab, uint keyno) { DBUG_ENTER("push_index_cond"); Item *idx_cond; - bool do_index_cond_pushdown= - ((tab->table->file->index_flags(keyno, 0, 1) & - HA_DO_INDEX_COND_PUSHDOWN) && - optimizer_flag(tab->join->thd, OPTIMIZER_SWITCH_INDEX_COND_PUSHDOWN)); - - /* - Do not try index condition pushdown on indexes which have partially-covered - columns. Unpacking from a column prefix into index tuple is not a supported - operation in some engines, see e.g. MySQL BUG#42991. - TODO: a better solution would be not to consider partially-covered columns - as parts of the index and still produce/check index condition for - fully-covered index columns. - */ - KEY *key_info= tab->table->key_info + keyno; - for (uint kp= 0; kp < key_info->key_parts; kp++) - { - if ((key_info->key_part[kp].key_part_flag & HA_PART_KEY_SEG)) - { - do_index_cond_pushdown= FALSE; - break; - } - } - if (do_index_cond_pushdown) + if ((tab->table->file->index_flags(keyno, 0, 1) & + HA_DO_INDEX_COND_PUSHDOWN) && + optimizer_flag(tab->join->thd, OPTIMIZER_SWITCH_INDEX_COND_PUSHDOWN) && + tab->join->thd->lex->sql_command != SQLCOM_UPDATE_MULTI && + tab->join->thd->lex->sql_command != SQLCOM_DELETE_MULTI && + tab->type != JT_CONST && tab->type != JT_SYSTEM) { DBUG_EXECUTE("where", print_where(tab->select_cond, "full cond", QT_ORDINARY);); @@ -356,7 +375,8 @@ void push_index_cond(JOIN_TAB *tab, uint keyno) tab->ref.disable_cache= TRUE; Item *row_cond= tab->idx_cond_fact_out ? - make_cond_remainder(tab->select_cond, TRUE) : + make_cond_remainder(tab->select_cond, tab->table, keyno, + tab->icp_other_tables_ok, TRUE) : tab->pre_idx_push_select_cond; DBUG_EXECUTE("where", |