Commit c7fdbffa authored by unknown's avatar unknown
Browse files

Fix for bug #8164: subquery with INFORMATION_SCHEMA.COLUMNS, 100 % CPU

parent 66d2d13a

mysql-test/r/information_schema.result

+7 −0
Original line number Diff line number Diff line
@@ -631,3 +631,10 @@ TABLES UPDATE_TIME datetime 
TABLES	CHECK_TIME	datetime

ROUTINES	CREATED	datetime

ROUTINES	LAST_ALTERED	datetime

SELECT COUNT(*) FROM INFORMATION_SCHEMA.TABLES A

WHERE NOT EXISTS 

(SELECT * FROM INFORMATION_SCHEMA.COLUMNS B

WHERE A.TABLE_SCHEMA = B.TABLE_SCHEMA

AND A.TABLE_NAME = B.TABLE_NAME);

COUNT(*)

0

mysql-test/t/information_schema.test

+9 −0
Original line number Diff line number Diff line
@@ -400,3 +400,12 @@ information_schema.columns 
where data_type = 'longtext';

select table_name, column_name, data_type from information_schema.columns

where data_type = 'datetime';



#

# Bug #8164  subquery with INFORMATION_SCHEMA.COLUMNS, 100 % CPU

#

SELECT COUNT(*) FROM INFORMATION_SCHEMA.TABLES A

WHERE NOT EXISTS 

(SELECT * FROM INFORMATION_SCHEMA.COLUMNS B

  WHERE A.TABLE_SCHEMA = B.TABLE_SCHEMA

  AND A.TABLE_NAME = B.TABLE_NAME);

sql/sql_show.cc

+4 −0
Original line number Diff line number Diff line
@@ -1649,6 +1649,10 @@ bool uses_only_table_name_fields(Item *item, TABLE_LIST *table) 
                               strlen(item_field->field_name), 0)))

      return 0;

  }

  if (item->type() == Item::SUBSELECT_ITEM &&

      !item->const_item())

    return 0;



  return 1;

}