#
# MDEV-16917: do not use splitting for derived with join cache
#
CREATE TABLE t1 (
n1 int(10) NOT NULL,
n2 int(10) NOT NULL,
c1 char(1) NOT NULL,
KEY c1 (c1),
KEY n1_c1_n2 (n1,c1,n2)
) ENGINE=InnoDB;
INSERT INTO t1 VALUES (0, 2, 'a'), (1, 3, 'a');
ANALYZE TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	OK
EXPLAIN SELECT t1.n1 FROM t1, (SELECT n1, n2 FROM t1 WHERE c1 = 'a' GROUP BY n1) as t
WHERE t.n1 = t1.n1 AND t.n2 = t1.n2 AND c1 = 'a' GROUP BY n1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	index	c1,n1_c1_n2	n1_c1_n2	9	NULL	2	Using where; Using index
1	PRIMARY	<derived2>	ref	key0	key0	8	test.t1.n1,test.t1.n2	2	
2	LATERAL DERIVED	t1	ref	c1,n1_c1_n2	n1_c1_n2	4	test.t1.n1	1	Using where; Using index
SELECT t1.n1 FROM t1, (SELECT n1, n2 FROM t1 WHERE c1 = 'a' GROUP BY n1) as t
WHERE t.n1 = t1.n1 AND t.n2 = t1.n2 AND c1 = 'a' GROUP BY n1;
n1
0
1
DROP TABLE t1;