From b1e55680437cefcfa087fd7531c0d351da87306e Mon Sep 17 00:00:00 2001 From: unknown Date: Wed, 11 Jul 2007 18:45:35 -0700 Subject: Fixed bug #29604. A bug in the restore_prev_nj_state function allowed interleaving inner tables of outer join operations with outer tables. With the current implementation of the nested loops algorithm it could lead to wrong result sets for queries with nested outer joins. Another bug in this procedure effectively blocked evaluation of some valid execution plans for queries with nested outer joins. mysql-test/r/join_nested.result: Added a test case for bug #29604. mysql-test/t/join_nested.test: Added a test case for bug #29604. --- sql/sql_select.cc | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'sql/sql_select.cc') diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 9d27ab4bb4e..c62a19b2752 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -8486,9 +8486,15 @@ static void restore_prev_nj_state(JOIN_TAB *last) { TABLE_LIST *last_emb= last->table->pos_in_table_list->embedding; JOIN *join= last->join; - while (last_emb && !(--last_emb->nested_join->counter)) + while (last_emb) { - join->cur_embedding_map &= last_emb->nested_join->nj_map; + if (!(--last_emb->nested_join->counter)) + join->cur_embedding_map&= ~last_emb->nested_join->nj_map; + else if (last_emb->nested_join->join_list.elements-1 == + last_emb->nested_join->counter) + join->cur_embedding_map|= last_emb->nested_join->nj_map; + else + break; last_emb= last_emb->embedding; } } -- cgit v1.2.1