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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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4
sql/sql_prepare.cc
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@ -2362,11 +2362,15 @@ void reinit_stmt_before_use(THD *thd, LEX *lex)
sl->where= sl->prep_where->copy_andor_structure(thd);
sl->where->cleanup();
}
else
sl->where= NULL;
if (sl->prep_having)
{
sl->having= sl->prep_having->copy_andor_structure(thd);
sl->having->cleanup();
}
else
sl->having= NULL;
DBUG_ASSERT(sl->join == 0);
ORDER *order;
/* Fix GROUP list */