diff --git a/mysql-test/r/join.result b/mysql-test/r/join.result index 7d6ef5b40ba..bacfa81160a 100644 --- a/mysql-test/r/join.result +++ b/mysql-test/r/join.result @@ -913,4 +913,21 @@ ON t4.a = t5.a ON t1.a = t3.a; a a a a a a DROP TABLE t1,t2,t3,t4,t5,t6; +# +# Bug#48483: crash in get_best_combination() +# +CREATE TABLE t1(f1 INT); +INSERT INTO t1 VALUES (1),(2); +CREATE VIEW v1 AS SELECT 1 FROM t1 LEFT JOIN t1 AS t2 on 1=1; +EXPLAIN EXTENDED +SELECT 1 FROM v1 right join v1 AS v2 ON RAND(); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 ALL NULL NULL NULL NULL 2 +1 SIMPLE t2 ALL NULL NULL NULL NULL 2 +1 SIMPLE t1 ALL NULL NULL NULL NULL 2 +1 SIMPLE t2 ALL NULL NULL NULL NULL 2 +Warnings: +Note 1003 select 1 AS `1` from `test`.`t1` left join `test`.`t1` `t2` on((1 = 1)) left join (`test`.`t1` left join `test`.`t1` `t2` on((1 = 1))) on(rand()) where 1 +DROP VIEW v1; +DROP TABLE t1; End of 5.0 tests. diff --git a/mysql-test/t/join.test b/mysql-test/t/join.test index 5b91d89836c..ba61da289bc 100644 --- a/mysql-test/t/join.test +++ b/mysql-test/t/join.test @@ -713,4 +713,16 @@ FROM DROP TABLE t1,t2,t3,t4,t5,t6; +--echo # +--echo # Bug#48483: crash in get_best_combination() +--echo # + +CREATE TABLE t1(f1 INT); +INSERT INTO t1 VALUES (1),(2); +CREATE VIEW v1 AS SELECT 1 FROM t1 LEFT JOIN t1 AS t2 on 1=1; +EXPLAIN EXTENDED +SELECT 1 FROM v1 right join v1 AS v2 ON RAND(); +DROP VIEW v1; +DROP TABLE t1; + --echo End of 5.0 tests. diff --git a/sql/sql_select.cc b/sql/sql_select.cc index eecc2b086a3..cbc608ea972 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -4819,6 +4819,11 @@ greedy_search(JOIN *join, if (best_extension_by_limited_search(join, remaining_tables, idx, record_count, read_time, search_depth, prune_level)) DBUG_RETURN(TRUE); + /* + 'best_read < DBL_MAX' means that optimizer managed to find + some plan and updated 'best_positions' array accordingly. + */ + DBUG_ASSERT(join->best_read < DBL_MAX); if (size_remain <= search_depth) { @@ -8431,8 +8436,14 @@ simplify_joins(JOIN *join, List *join_list, COND *conds, bool top) we still make the inner tables dependent on the outer tables. It would be enough to set dependency only on one outer table for them. Yet this is really a rare case. + Note: + RAND_TABLE_BIT mask should not be counted as it + prevents update of inner table dependences. + For example it might happen if RAND() function + is used in JOIN ON clause. */ - if (!(prev_table->on_expr->used_tables() & ~prev_used_tables)) + if (!((prev_table->on_expr->used_tables() & ~RAND_TABLE_BIT) & + ~prev_used_tables)) prev_table->dep_tables|= used_tables; } }