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SET @save_innodb_stats_persistent=@@GLOBAL.innodb_stats_persistent;
SET GLOBAL innodb_stats_persistent=0;
#
# 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');
insert into t1 select seq+1,seq+2,'c' from seq_1_to_1000;
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 ref c1,n1_c1_n2 c1 1 const 2 Using index condition; Using where; Using temporary; Using filesort
1 PRIMARY <derived2> ref key0 key0 8 test.t1.n1,test.t1.n2 1
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 1
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 1
2 LATERAL DERIVED t1 eq_ref PRIMARY PRIMARY 4 test.t2.id 1
set join_cache_level=default;
DROP TABLE t1,t2;
#
# Bug mdev-18467: join of grouping view and a base table as inner operand
# of left join with on condition containing impossible range
#
create table t1 (f1 int, f2 int, key(f2)) engine=InnoDB;
insert into t1 values (3,33), (7,77), (1,11);
create table t2 (f1 int, f2 int, primary key (f1)) engine=InnoDB;
insert into t2 values (3,33), (9,99), (1,11);
create view v1 as
select f1, max(f2) as f2 from t2 group by f1;
select t.f2
from t1
left join
(v1 join t1 as t on v1.f1=t.f1 and t.f2 = null)
on t1.f1=t.f1;
f2
NULL
NULL
NULL
explain select t.f2
from t1
left join
(v1 join t1 as t on v1.f1=t.f1 and t.f2 = null)
on t1.f1=t.f1;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t const f2 NULL NULL NULL 0 Impossible ON condition
1 PRIMARY <derived2> const key0,key1 NULL NULL NULL 0 Impossible ON condition
1 PRIMARY t1 ALL NULL NULL NULL NULL 3
2 DERIVED t2 ALL PRIMARY NULL NULL NULL 3 Using temporary; Using filesort
set statement optimizer_switch='split_materialized=off' for explain select t.f2
from t1
left join
(v1 join t1 as t on v1.f1=t.f1 and t.f2 = null)
on t1.f1=t.f1;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t const f2 NULL NULL NULL 0 Impossible ON condition
1 PRIMARY <derived3> const key0,key1 NULL NULL NULL 0 Impossible ON condition
1 PRIMARY t1 ALL NULL NULL NULL NULL 3
3 DERIVED t2 index NULL PRIMARY 4 NULL 3
drop view v1;
drop table t1,t2;
#
# MDEV-23723: Crash when test_if_skip_sort_order() is checked for derived table subject to split
#
CREATE TABLE t1 (a INT, b INT, KEY (a), KEY (a,b)) ENGINE=InnoDB;
CREATE TABLE t2 (c INT, KEY (c)) ENGINE=InnoDB;
SELECT * FROM t1 t1a JOIN t1 t1b;
a b a b
INSERT INTO t2 VALUES (1),(2);
INSERT INTO t1 VALUES (1,2),(3,4),(5,6),(7,8),(9,10),(11,12);
set statement optimizer_switch='split_materialized=off' for EXPLAIN
SELECT *
FROM
t1 JOIN
(SELECT t1_inner.a, t1_inner.b FROM t1 as t1_inner, t2 as t2_inner WHERE t1_inner.b = t2_inner.c GROUP BY t1_inner.a, t1_inner.b) as dt
WHERE
t1.a = dt.a;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 index a,a_2 a_2 10 NULL 6 Using where; Using index
1 PRIMARY <derived3> ref key0 key0 5 test.t1.a 1
3 DERIVED t1_inner index NULL a_2 10 NULL 6 Using where; Using index
3 DERIVED t2_inner ref c c 5 test.t1_inner.b 1 Using index
set statement optimizer_switch='split_materialized=on' for EXPLAIN
SELECT *
FROM
t1 JOIN
(SELECT t1_inner.a, t1_inner.b FROM t1 as t1_inner, t2 as t2_inner WHERE t1_inner.b = t2_inner.c GROUP BY t1_inner.a, t1_inner.b) as dt
WHERE
t1.a = dt.a;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 index a,a_2 a_2 10 NULL 6 Using where; Using index
1 PRIMARY <derived3> ref key0 key0 5 test.t1.a 1
3 DERIVED t1_inner index a,a_2 a_2 10 NULL 6 Using where; Using index
3 DERIVED t2_inner ref c c 5 test.t1_inner.b 1 Using index
DROP TABLE t1, t2;
#
# Bug mdev-25714: usage non-splitting covering index is cheaper than
# usage of the best splitting index for one group
#
create table t1 (
id int not null, itemid int not null, index idx (itemid)
) engine=innodb;
insert into t1 values (1, 2), (2,2), (4,2), (4,2), (0,3), (3,3);
create table t2 (id int not null) engine=innodb;
insert into t2 values (2);
create table t3 (
id int not null, itemid int not null, userid int not null, primary key (id),
index idx1 (userid, itemid), index idx2 (itemid)
) engine innodb;
insert into t3 values (1,1,1), (2,1,1), (3,2,1), (4,2,1), (5,3,1);
set use_stat_tables='never';
set optimizer_use_condition_selectivity=1;
analyze table t1,t2,t3;
Table Op Msg_type Msg_text
test.t1 analyze status OK
test.t2 analyze status OK
test.t3 analyze status OK
set optimizer_switch='split_materialized=on';
explain select t1.id, t1.itemid, dt.id, t2.id
from t1,
(select itemid, max(id) as id from t3 where userid = 1 group by itemid) dt,
t2
where t1.id = dt.id and t1.itemid = dt.itemid and t2.id=t1.itemid;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 1
1 PRIMARY <derived2> ref key1 key1 4 test.t2.id 1
1 PRIMARY t1 ref idx idx 4 test.t2.id 3 Using where
2 DERIVED t3 ref idx1,idx2 idx1 4 const 5 Using where; Using index
select t1.id, t1.itemid, dt.id, t2.id
from t1,
(select itemid, max(id) as id from t3 where userid = 1 group by itemid) dt,
t2
where t1.id = dt.id and t1.itemid = dt.itemid and t2.id=t1.itemid;
id itemid id id
4 2 4 2
4 2 4 2
set optimizer_switch='split_materialized=off';
explain select t1.id, t1.itemid, dt.id, t2.id
from t1,
(select itemid, max(id) as id from t3 where userid = 1 group by itemid) dt,
t2
where t1.id = dt.id and t1.itemid = dt.itemid and t2.id=t1.itemid;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 1
1 PRIMARY <derived2> ref key1 key1 4 test.t2.id 1
1 PRIMARY t1 ref idx idx 4 test.t2.id 3 Using where
2 DERIVED t3 ref idx1 idx1 4 const 5 Using where; Using index
select t1.id, t1.itemid, dt.id, t2.id
from t1,
(select itemid, max(id) as id from t3 where userid = 1 group by itemid) dt,
t2
where t1.id = dt.id and t1.itemid = dt.itemid and t2.id=t1.itemid;
id itemid id id
4 2 4 2
4 2 4 2
drop table t1,t2,t3;
set optimizer_switch='split_materialized=default';
set use_stat_tables=default;
set optimizer_use_condition_selectivity=default;
#
# MDEV-26337: subquery with groupby and ROLLUP returns incorrect results
# (The testcase is taken from testcase for MDEV-13389 due to it being
# much smaller)
#
create table t3 (a int, b int, c char(127), index idx_b(b)) engine=myisam;
insert into t3 values
(8,11,'aa'), (5,15,'cc'), (1,14,'bb'), (2,12,'aa'), (7,17,'cc'),
(7,18,'aa'), (2,11,'aa'), (7,10,'bb'), (3,11,'dd'), (4,12,'ee'),
(5,14,'dd'), (9,12,'ee');
create table t4 (a int, b int, c char(127), index idx(a,c)) engine=myisam;
insert into t4 values
(7,10,'cc'), (1,20,'aa'), (2,23,'bb'), (7,18,'cc'), (1,30,'bb'),
(4,71,'xx'), (3,15,'aa'), (7,82,'aa'), (8,12,'dd'), (4,15,'aa'),
(11,33,'yy'), (10,42,'zz'), (4,53,'xx'), (10,17,'yy'), (7,12,'cc'),
(8,20,'dd'), (7,32,'bb'), (1,50,'aa'), (3,40,'bb'), (3,77,'aa');
insert into t4 select a+10, b+10, concat(c,'f') from t4;
analyze table t3,t4;
Table Op Msg_type Msg_text
test.t3 analyze status Engine-independent statistics collected
test.t3 analyze status OK
test.t4 analyze status Engine-independent statistics collected
test.t4 analyze status OK
# This should use a plan with LATERAL DERIVED:
explain select t3.a,t3.c,t.max,t.min
from t3 join
(select a, c, max(b) max, min(b) min from t4 group by a,c) t
on t3.a=t.a and t3.c=t.c
where t3.b > 15;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t3 range idx_b idx_b 5 NULL 2 Using index condition; Using where
1 PRIMARY <derived2> ref key0 key0 133 test.t3.a,test.t3.c 1
2 LATERAL DERIVED t4 ref idx idx 133 test.t3.a,test.t3.c 1
# ... and if one adds WITH ROLLUP, then LATERAL DERIVED is no longer used:
explain select t3.a,t3.c,t.max,t.min
from t3 join
(select a, c, max(b) max, min(b) min from t4 group by a,c with rollup) t
on t3.a=t.a and t3.c=t.c
where t3.b > 15;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t3 range idx_b idx_b 5 NULL 2 Using index condition; Using where
1 PRIMARY <derived2> ref key0 key0 133 test.t3.a,test.t3.c 4
2 DERIVED t4 ALL NULL NULL NULL NULL 40 Using filesort
drop table t3, t4;
# End of 10.3 tests
SET GLOBAL innodb_stats_persistent=@save_innodb_stats_persistent;
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