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Bug#54494 crash with explain extended and prepared statements

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In case of outer join and emtpy WHERE conditon
'always true' condition is created for WHERE clasue.
Later in mysql_select() original SELECT_LEX WHERE
condition is overwritten with created cond.
However SELECT_LEX condition is also used as inital
condition in mysql_select()->JOIN::prepare().
On second execution of PS modified SELECT_LEX condition
is taken and it leads to crash.
The fix is to restore original SELECT_LEX condition
(set to NULL if original cond is NULL) in
 reinit_stmt_before_use().
HAVING clause is fixed too for safety reason
(no test case as I did not manage to think out
 appropriate example).


mysql-test/r/ps.result:
  test case
mysql-test/t/ps.test:
  test case
sql/sql_prepare.cc:
  restore original SELECT_LEX condition
  (set to NULL if original cond is NULL) in
   reinit_stmt_before_use()
This commit is contained in:
Sergey Glukhov
2010-09-23 10:43:51 +04:00
parent d695cc864c
commit b76277fce5
3 changed files with 35 additions and 0 deletions
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11
mysql-test/t/ps.test
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@ -3079,4 +3079,15 @@ EXECUTE stmt;
DEALLOCATE PREPARE stmt;
DROP TABLE t1;
--echo #
--echo # Bug#54494 crash with explain extended and prepared statements
--echo #
CREATE TABLE t1(a INT);
INSERT INTO t1 VALUES (1),(2);
PREPARE stmt FROM 'EXPLAIN EXTENDED SELECT 1 FROM t1 RIGHT JOIN t1 t2 ON 1';
EXECUTE stmt;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
DROP TABLE t1;
--echo End of 5.1 tests.