diff --git a/mysql-test/r/join_outer.result b/mysql-test/r/join_outer.result index 1e4fc91b8bd..083be3737f7 100644 --- a/mysql-test/r/join_outer.result +++ b/mysql-test/r/join_outer.result @@ -1254,3 +1254,38 @@ SELECT * FROM t1 LEFT JOIN t2 ON e<>0 WHERE c=1 AND d<=>NULL; c e d 1 0 NULL DROP TABLE t1,t2; +# +# Bug#47650: using group by with rollup without indexes returns incorrect +# results with where +# +CREATE TABLE t1 ( a INT ); +INSERT INTO t1 VALUES (1); +CREATE TABLE t2 ( a INT, b INT ); +INSERT INTO t2 VALUES (1, 1),(1, 2),(1, 3),(2, 4),(2, 5); +EXPLAIN +SELECT t1.a, COUNT( t2.b ), SUM( t2.b ), MAX( t2.b ) +FROM t1 LEFT JOIN t2 USING( a ) +GROUP BY t1.a WITH ROLLUP; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 system NULL NULL NULL NULL 1 Using temporary; Using filesort +1 SIMPLE t2 ALL NULL NULL NULL NULL 5 +SELECT t1.a, COUNT( t2.b ), SUM( t2.b ), MAX( t2.b ) +FROM t1 LEFT JOIN t2 USING( a ) +GROUP BY t1.a WITH ROLLUP; +a COUNT( t2.b ) SUM( t2.b ) MAX( t2.b ) +1 3 6 3 +NULL 3 6 3 +EXPLAIN +SELECT t1.a, COUNT( t2.b ), SUM( t2.b ), MAX( t2.b ) +FROM t1 JOIN t2 USING( a ) +GROUP BY t1.a WITH ROLLUP; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 system NULL NULL NULL NULL 1 Using filesort +1 SIMPLE t2 ALL NULL NULL NULL NULL 5 Using where +SELECT t1.a, COUNT( t2.b ), SUM( t2.b ), MAX( t2.b ) +FROM t1 JOIN t2 USING( a ) +GROUP BY t1.a WITH ROLLUP; +a COUNT( t2.b ) SUM( t2.b ) MAX( t2.b ) +1 3 6 3 +NULL 3 6 3 +DROP TABLE t1, t2; diff --git a/mysql-test/t/join_outer.test b/mysql-test/t/join_outer.test index 35aec71ebb8..aeaa69657c6 100644 --- a/mysql-test/t/join_outer.test +++ b/mysql-test/t/join_outer.test @@ -867,3 +867,32 @@ SELECT * FROM t1 LEFT JOIN t2 ON e<>0 WHERE c=1 AND d<=>NULL; DROP TABLE t1,t2; +--echo # +--echo # Bug#47650: using group by with rollup without indexes returns incorrect +--echo # results with where +--echo # +CREATE TABLE t1 ( a INT ); +INSERT INTO t1 VALUES (1); + +CREATE TABLE t2 ( a INT, b INT ); +INSERT INTO t2 VALUES (1, 1),(1, 2),(1, 3),(2, 4),(2, 5); + +EXPLAIN +SELECT t1.a, COUNT( t2.b ), SUM( t2.b ), MAX( t2.b ) +FROM t1 LEFT JOIN t2 USING( a ) +GROUP BY t1.a WITH ROLLUP; + +SELECT t1.a, COUNT( t2.b ), SUM( t2.b ), MAX( t2.b ) +FROM t1 LEFT JOIN t2 USING( a ) +GROUP BY t1.a WITH ROLLUP; + +EXPLAIN +SELECT t1.a, COUNT( t2.b ), SUM( t2.b ), MAX( t2.b ) +FROM t1 JOIN t2 USING( a ) +GROUP BY t1.a WITH ROLLUP; + +SELECT t1.a, COUNT( t2.b ), SUM( t2.b ), MAX( t2.b ) +FROM t1 JOIN t2 USING( a ) +GROUP BY t1.a WITH ROLLUP; + +DROP TABLE t1, t2; diff --git a/sql/sql_select.cc b/sql/sql_select.cc index cbee09f1fdb..6383fe63012 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -7124,7 +7124,19 @@ remove_const(JOIN *join,ORDER *first_order, COND *cond, for (order=first_order; order ; order=order->next) { table_map order_tables=order->item[0]->used_tables(); - if (order->item[0]->with_sum_func) + if (order->item[0]->with_sum_func || + /* + If the outer table of an outer join is const (either by itself or + after applying WHERE condition), grouping on a field from such a + table will be optimized away and filesort without temporary table + will be used unless we prevent that now. Filesort is not fit to + handle joins and the join condition is not applied. We can't detect + the case without an expensive test, however, so we force temporary + table for all queries containing more than one table, ROLLUP, and an + outer join. + */ + (join->tables > 1 && join->rollup.state == ROLLUP::STATE_INITED && + join->outer_join)) *simple_order=0; // Must do a temp table to sort else if (!(order_tables & not_const_tables)) {