diff --git a/mysql-test/r/group_min_max.result b/mysql-test/r/group_min_max.result index 7c9ff6d9fa1..534e85038fe 100644 --- a/mysql-test/r/group_min_max.result +++ b/mysql-test/r/group_min_max.result @@ -3243,4 +3243,40 @@ d 4 f 7 g 8 drop table t1; +# +# MDEV-4140 Wrong result with GROUP BY + multipart key + MIN/MAX loose scan and a subquery +# +CREATE TABLE t1 (a int, b int, KEY (b, a)) ; +INSERT INTO t1 VALUES (0,99),(9,99),(4,0),(7,0),(99,0),(7,0),(8,0),(99,0),(1,0); +CREATE TABLE t2 (c int) ; +INSERT INTO t2 VALUES (0),(1); +EXPLAIN +SELECT MIN(a), b FROM t1 WHERE a > 0 GROUP BY b; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range NULL b 10 NULL 10 Using where; Using index for group-by +SELECT MIN(a), b FROM t1 WHERE a > 0 GROUP BY b; +MIN(a) b +1 0 +9 99 +EXPLAIN +SELECT MIN(a), b FROM t1 WHERE a > ( SELECT c FROM t2 WHERE c = 0 ) GROUP BY b; +id select_type table type possible_keys key key_len ref rows Extra +1 PRIMARY t1 index NULL b 10 NULL 9 Using where; Using index +2 SUBQUERY t2 ALL NULL NULL NULL NULL 2 Using where +SELECT MIN(a), b FROM t1 WHERE a > ( SELECT c FROM t2 WHERE c = 0 ) GROUP BY b; +MIN(a) b +1 0 +9 99 +EXPLAIN +SELECT MIN(a), b FROM t1 WHERE a > ( SELECT min(c) FROM t2, t1 t1a, t1 t1b WHERE c = 0 ) GROUP BY b; +id select_type table type possible_keys key key_len ref rows Extra +1 PRIMARY t1 index NULL b 10 NULL 9 Using where; Using index +2 SUBQUERY t2 ALL NULL NULL NULL NULL 2 Using where +2 SUBQUERY t1a index NULL b 10 NULL 9 Using index; Using join buffer (flat, BNL join) +2 SUBQUERY t1b index NULL b 10 NULL 9 Using index; Using join buffer (incremental, BNL join) +SELECT MIN(a), b FROM t1 WHERE a > ( SELECT min(c) FROM t2, t1 t1a, t1 t1b WHERE c = 0 ) GROUP BY b; +MIN(a) b +1 0 +9 99 +drop table t1, t2; End of 5.3 tests diff --git a/mysql-test/t/group_min_max.test b/mysql-test/t/group_min_max.test index d081ad6e09b..28d375f7dda 100644 --- a/mysql-test/t/group_min_max.test +++ b/mysql-test/t/group_min_max.test @@ -1239,4 +1239,26 @@ SELECT b, min(a) FROM t1 WHERE (a > '0' AND (a > '1' OR b = 'd')) GROUP BY b; drop table t1; +--echo # +--echo # MDEV-4140 Wrong result with GROUP BY + multipart key + MIN/MAX loose scan and a subquery +--echo # + +CREATE TABLE t1 (a int, b int, KEY (b, a)) ; +INSERT INTO t1 VALUES (0,99),(9,99),(4,0),(7,0),(99,0),(7,0),(8,0),(99,0),(1,0); +CREATE TABLE t2 (c int) ; +INSERT INTO t2 VALUES (0),(1); + +EXPLAIN +SELECT MIN(a), b FROM t1 WHERE a > 0 GROUP BY b; +SELECT MIN(a), b FROM t1 WHERE a > 0 GROUP BY b; +EXPLAIN +SELECT MIN(a), b FROM t1 WHERE a > ( SELECT c FROM t2 WHERE c = 0 ) GROUP BY b; +SELECT MIN(a), b FROM t1 WHERE a > ( SELECT c FROM t2 WHERE c = 0 ) GROUP BY b; +# this test is for 5.5 to ensure that the subquery is expensive +EXPLAIN +SELECT MIN(a), b FROM t1 WHERE a > ( SELECT min(c) FROM t2, t1 t1a, t1 t1b WHERE c = 0 ) GROUP BY b; +SELECT MIN(a), b FROM t1 WHERE a > ( SELECT min(c) FROM t2, t1 t1a, t1 t1b WHERE c = 0 ) GROUP BY b; + +drop table t1, t2; + --echo End of 5.3 tests diff --git a/sql/opt_range.cc b/sql/opt_range.cc index 7a6c390f210..29f3945d163 100644 --- a/sql/opt_range.cc +++ b/sql/opt_range.cc @@ -12236,7 +12236,7 @@ check_group_min_max_predicates(Item *cond, Item_field *min_max_arg_item, &has_min_max, &has_other)) DBUG_RETURN(FALSE); } - else if (cur_arg->const_item()) + else if (cur_arg->const_item() && !cur_arg->is_expensive()) { /* For predicates of the form "const OP expr" we also have to check 'expr'