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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 Engine-independent statistics collected
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;
#
# MDEV-17211: splittable materialized derived joining 3 tables with
# GROUP BY list containing fields from 2 of them
#
CREATE TABLE t1 (
id1 int, i1 int, id2 int,
PRIMARY KEY (id1), KEY (i1), KEY (id2)
) ENGINE=InnoDB;
INSERT INTO t1 VALUES (1,1,1);
CREATE TABLE t2 (id2 int, i2 int) ENGINE=InnoDB;
INSERT INTO t2 VALUES (1, 1);
CREATE TABLE t3 (id3 int, i3 int, PRIMARY KEY (id3)) ENGINE=InnoDB;
INSERT INTO t3 VALUES (1,1);
EXPLAIN SELECT id3
FROM (SELECT t3.id3, t2.i2, t1.id2 FROM t3,t1,t2
WHERE t3.i3=t1.id1 AND t2.id2=t1.id2
GROUP BY t3.id3, t1.id2) AS t,
t2
WHERE t2.id2=t.id2;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 1 Using where
1 PRIMARY <derived2> ref key0 key0 5 test.t2.id2 2
2 DERIVED t3 ALL NULL NULL NULL NULL 1 Using where; Using temporary; Using filesort
2 DERIVED t1 eq_ref PRIMARY,id2 PRIMARY 4 test.t3.i3 1
2 DERIVED t2 ALL NULL NULL NULL NULL 1 Using where; Using join buffer (flat, BNL join)
SELECT id3
FROM (SELECT t3.id3, t2.i2, t1.id2 FROM t3,t1,t2
WHERE t3.i3=t1.id1 AND t2.id2=t1.id2
GROUP BY t3.id3, t1.id2) AS t,
t2
WHERE t2.id2=t.id2;
id3
1
DROP TABLE t1,t2,t3;
#
# Bug mdev-17381: equi-join of derived table with join_cache_level=4
#
CREATE TABLE t1 (
id int NOT NULL,
amount decimal DEFAULT NULL,
PRIMARY KEY (id)
) ENGINE=INNODB;
CREATE TABLE t2 (
id int NOT NULL,
name varchar(50) DEFAULT NULL,
PRIMARY KEY (id)
) ENGINE=INNODB;
INSERT INTO t1 VALUES
(1, 10.0000), (2, 20.0000), (3, 30.0000), (4, 40.0000),
(5, NULL), (6, NULL), (7, 70.0000), (8, 80.0000);
INSERT INTO t2 VALUES
(1,'A'), (2,'B'), (3,'C'), (4,'D'), (5, NULL), (6, NULL),
(7,'E'), (8,'F'), (9,'G'), (10,'H'), (11, NULL), (12, NULL);
set join_cache_level=4;
SELECT t2.id,t2.name,t.total_amt
FROM t2
LEFT JOIN
(SELECT id, sum(amount) total_amt FROM t1 GROUP BY id) AS t
ON t2.id=t.id
WHERE t2.id < 3;
id name total_amt
1 A 10
2 B 20
EXPLAIN SELECT t2.id,t2.name,t.total_amt
FROM t2
LEFT JOIN
(SELECT id, sum(amount) total_amt FROM t1 GROUP BY id) AS t
ON t2.id=t.id
WHERE t2.id < 3;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t2 range PRIMARY PRIMARY 4 NULL 2 Using where
1 PRIMARY <derived2> ref key0 key0 5 test.t2.id 2
2 LATERAL DERIVED t1 eq_ref PRIMARY PRIMARY 4 test.t2.id 1
set join_cache_level=default;
DROP TABLE t1,t2;
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