diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 02ec7ae08ed..da96c98cd4f 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -932,17 +932,28 @@ JOIN::optimize() tmp_table_param.hidden_field_count= (all_fields.elements - fields_list.elements); + ORDER *tmp_group= ((!simple_group && !procedure && + !(test_flags & TEST_NO_KEY_GROUP)) ? group_list : + (ORDER*) 0); + /* + Pushing LIMIT to the temporary table creation is not applicable + when there is ORDER BY or GROUP BY or there is no GROUP BY, but + there are aggregate functions, because in all these cases we need + all result rows. + */ + ha_rows tmp_rows_limit= ((order == 0 || skip_sort_order || + test(select_options & OPTION_BUFFER_RESULT)) && + !tmp_group && + !thd->lex->current_select->with_sum_func) ? + select_limit : HA_POS_ERROR; + if (!(exec_tmp_table1 = create_tmp_table(thd, &tmp_table_param, all_fields, - ((!simple_group && !procedure && - !(test_flags & TEST_NO_KEY_GROUP)) ? - group_list : (ORDER*) 0), + tmp_group, group_list ? 0 : select_distinct, group_list && simple_group, select_options, - (order == 0 || skip_sort_order || - test(select_options & OPTION_BUFFER_RESULT)) ? - select_limit : HA_POS_ERROR, + tmp_rows_limit, (char *) ""))) DBUG_RETURN(1); @@ -5566,6 +5577,13 @@ create_tmp_table(THD *thd,TMP_TABLE_PARAM *param,List &fields, thd->variables.max_heap_table_size) : thd->variables.tmp_table_size)/ table->reclength); set_if_bigger(table->max_rows,1); // For dummy start options + /* + Push the LIMIT clause to the temporary table creation, so that we + materialize only up to 'rows_limit' records instead of all result records. + */ + set_if_smaller(table->max_rows, rows_limit); + param->end_write_records= rows_limit; + keyinfo=param->keyinfo; if (group) @@ -5686,19 +5704,6 @@ create_tmp_table(THD *thd,TMP_TABLE_PARAM *param,List &fields, } } - /* - Push the LIMIT clause to the temporary table creation, so that we - materialize only up to 'rows_limit' records instead of all result records. - This optimization is not applicable when there is GROUP BY or there is - no GROUP BY, but there are aggregate functions, because both must be - computed for all result rows. - */ - if (!group && !thd->lex->current_select->with_sum_func) - { - set_if_smaller(table->max_rows, rows_limit); - param->end_write_records= rows_limit; - } - if (thd->is_fatal_error) // If end of memory goto err; /* purecov: inspected */ table->db_record_offset=1;