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#
# 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;
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