From 66dfceb11fe2392c98ec0f481a01e8da7b4314b8 Mon Sep 17 00:00:00 2001 From: unknown Date: Wed, 30 May 2012 19:10:18 +0300 Subject: Fix for bug lp:1006231 Analysis: When a subquery that needs a temp table is executed during the prepare or optimize phase of the outer query, at the end of the subquery execution all the JOIN_TABs of the subquery are replaced by a new JOIN_TAB that selects from the temp table. However that temp table has no corresponding TABLE_LIST. Once EXPLAIN execution reaches its last phase, it tries to print the names of the subquery tables through its TABLE_LISTs, but in the case of this bug there is no such TABLE_LIST (it is NULL), hence a crash. Solution: The fix is to block subquery evaluation inside Item_func_like::fix_fields and Item_func_like::select_optimize() using the Item::is_expensive() test. --- mysql-test/t/subselect_innodb.test | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'mysql-test/t/subselect_innodb.test') diff --git a/mysql-test/t/subselect_innodb.test b/mysql-test/t/subselect_innodb.test index a0c52196412..26ff1072e30 100644 --- a/mysql-test/t/subselect_innodb.test +++ b/mysql-test/t/subselect_innodb.test @@ -356,4 +356,16 @@ WHERE f2 >= ( drop table t1, t2, t3; +--echo # +--echo # LP BUG#1006231 crash in select_describe +--echo # + +create table t1(a1 int) ENGINE=InnoDB; +insert into t1 values (1); +explain +select 1 from t1 where 1 like (select 1 from t1 where 1 <=> (select 1 from t1 group by a1)); +select 1 from t1 where 1 like (select 1 from t1 where 1 <=> (select 1 from t1 group by a1)); +drop table t1; + + set optimizer_switch=@subselect_innodb_tmp; -- cgit v1.2.1