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|
#
# LP BUG#643424 valgrind warning in choose_subquery_plan()
#
CREATE TABLE t1 (
pk int(11) NOT NULL AUTO_INCREMENT,
c1 int(11) DEFAULT NULL,
c2 int(11) DEFAULT NULL,
PRIMARY KEY (pk),
KEY c2 (c2));
INSERT INTO t1 VALUES (1,NULL,2);
INSERT INTO t1 VALUES (2,7,9);
INSERT INTO t1 VALUES (9,NULL,8);
CREATE TABLE t2 (
pk int(11) NOT NULL AUTO_INCREMENT,
c1 int(11) DEFAULT NULL,
c2 int(11) DEFAULT NULL,
PRIMARY KEY (pk),
KEY c2 (c2));
INSERT INTO t2 VALUES (1,1,7);
set @save_optimizer_switch=@@optimizer_switch;
set @@optimizer_switch='materialization=on,in_to_exists=on,semijoin=off';
SELECT pk FROM t1 WHERE (c2, c1) IN (SELECT c2, c2 FROM t2);
pk
set session optimizer_switch=@save_optimizer_switch;
drop table t1, t2;
#
# LP BUG#652727 Crash in create_ref_for_key()
#
CREATE TABLE t2 (
pk int(11) NOT NULL AUTO_INCREMENT,
c1 int(11) DEFAULT NULL,
PRIMARY KEY (pk));
INSERT INTO t2 VALUES (10,7);
INSERT INTO t2 VALUES (11,1);
INSERT INTO t2 VALUES (17,NULL);
CREATE TABLE t1 (
pk int(11) NOT NULL AUTO_INCREMENT,
c1 int(11) DEFAULT NULL,
PRIMARY KEY (pk));
INSERT INTO t1 VALUES (15,1);
INSERT INTO t1 VALUES (19,NULL);
CREATE TABLE t3 (c2 int(11) DEFAULT NULL, KEY c2 (c2));
INSERT INTO t3 VALUES (1);
set @save_optimizer_switch=@@optimizer_switch;
set @@optimizer_switch='materialization=on,in_to_exists=on,semijoin=off';
SELECT c2
FROM t3
WHERE (2, 6) IN (SELECT t1.c1, t1.c1 FROM t1 STRAIGHT_JOIN t2 ON t2.pk = t1.pk);
c2
set session optimizer_switch=@save_optimizer_switch;
drop table t1, t2, t3;
#
# LP BUG#641245 Crash in Item_equal::contains
#
CREATE TABLE t1 (
pk int(11) NOT NULL AUTO_INCREMENT,
c1 int(11) DEFAULT NULL,
c2 int(11) DEFAULT NULL,
c3 varchar(1) DEFAULT NULL,
c4 varchar(1) DEFAULT NULL,
PRIMARY KEY (pk),
KEY c2 (c2),
KEY c3 (c3,c2));
INSERT INTO t1 VALUES (10,7,8,'v','v');
INSERT INTO t1 VALUES (11,1,9,'r','r');
INSERT INTO t1 VALUES (12,5,9,'a','a');
INSERT INTO t1 VALUES (13,7,18,'v','v');
INSERT INTO t1 VALUES (14,1,19,'r','r');
INSERT INTO t1 VALUES (15,5,29,'a','a');
INSERT INTO t1 VALUES (17,7,38,'v','v');
INSERT INTO t1 VALUES (18,1,39,'r','r');
INSERT INTO t1 VALUES (19,5,49,'a','a');
create table t1a like t1;
insert into t1a select * from t1;
create table t1b like t1;
insert into t1b select * from t1;
CREATE TABLE t2 (
pk int(11) NOT NULL AUTO_INCREMENT,
c1 int(11) DEFAULT NULL,
c2 int(11) DEFAULT NULL,
c3 varchar(1) DEFAULT NULL,
c4 varchar(1) DEFAULT NULL,
PRIMARY KEY (pk),
KEY c2 (c2),
KEY c3 (c3,c2));
INSERT INTO t2 VALUES (1,NULL,2,'w','w');
INSERT INTO t2 VALUES (2,7,9,'m','m');
set @@optimizer_switch='materialization=off,in_to_exists=on,semijoin=off';
EXPLAIN EXTENDED SELECT pk
FROM t1
WHERE c1 IN
(SELECT t1a.c1
FROM (t1b JOIN t2 ON t2.c3 = t1b.c4) LEFT JOIN
t1a ON (t1a.c2 = t1b.pk AND 2)
WHERE t1.pk) ;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 9 100.00 Using where
2 DEPENDENT SUBQUERY t1b ALL NULL NULL NULL NULL 9 100.00
2 DEPENDENT SUBQUERY t1a ref c2 c2 5 test.t1b.pk 1 100.00 Using where
2 DEPENDENT SUBQUERY t2 index c3 c3 9 NULL 2 100.00 Using where; Using index; Using join buffer (flat, BNL join)
Warnings:
Note 1276 Field or reference 'test.t1.pk' of SELECT #2 was resolved in SELECT #1
Note 1003 /* select#1 */ select `test`.`t1`.`pk` AS `pk` from `test`.`t1` where <expr_cache><`test`.`t1`.`c1`,`test`.`t1`.`pk`>(<in_optimizer>(`test`.`t1`.`c1`,<exists>(/* select#2 */ select `test`.`t1a`.`c1` from `test`.`t1b` join `test`.`t2` left join `test`.`t1a` on(`test`.`t1a`.`c2` = `test`.`t1b`.`pk` and 2) where `test`.`t1`.`pk` <> 0 and <cache>(`test`.`t1`.`c1`) = `test`.`t1a`.`c1` and `test`.`t2`.`c3` = `test`.`t1b`.`c4`)))
SELECT pk
FROM t1
WHERE c1 IN
(SELECT t1a.c1
FROM (t1b JOIN t2 ON t2.c3 = t1b.c4) LEFT JOIN
t1a ON (t1a.c2 = t1b.pk AND 2)
WHERE t1.pk) ;
pk
DROP TABLE t1, t1a, t1b, t2;
#
# LP BUG#714808 Assertion `outer_lookup_keys <= outer_record_count'
# failed with materialization
CREATE TABLE t1 ( pk int(11), PRIMARY KEY (pk)) ;
CREATE TABLE t2 ( f2 int(11)) ;
CREATE TABLE t3 ( f1 int(11), f3 varchar(1), KEY (f1)) ;
INSERT INTO t3 VALUES (7,'f');
set @@optimizer_switch='materialization=on,in_to_exists=on,semijoin=off';
EXPLAIN
SELECT t1.*
FROM t3 RIGHT JOIN t1 ON t1.pk = t3.f1
WHERE t3.f3 OR ( 3 ) IN ( SELECT f2 FROM t2 );
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
2 SUBQUERY NULL NULL NULL NULL NULL NULL NULL no matching row in const table
SELECT t1.*
FROM t3 RIGHT JOIN t1 ON t1.pk = t3.f1
WHERE t3.f3 OR ( 3 ) IN ( SELECT f2 FROM t2 );
pk
drop table t1,t2,t3;
#
# LP BUG#714999 Second crash in select_describe() with nested subqueries
#
CREATE TABLE t1 ( pk int(11)) ;
INSERT INTO t1 VALUES (29);
CREATE TABLE t2 ( f1 varchar(1)) ;
INSERT INTO t2 VALUES ('f'),('d');
CREATE TABLE t3 ( f2 varchar(1)) ;
EXPLAIN SELECT f2 FROM t3 WHERE (
SELECT MAX( pk ) FROM t1
WHERE EXISTS (
SELECT max(f1)
FROM t2 GROUP BY f1
)
) IS NULL ;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
2 SUBQUERY t1 system NULL NULL NULL NULL 1
3 SUBQUERY t2 ALL NULL NULL NULL NULL 2 Using temporary
drop table t1, t2, t3;
#
# LP BUG#715034 Item_sum_distinct::clear(): Assertion `tree != 0' failed
#
CREATE TABLE t2 ( f2 int(11)) ;
CREATE TABLE t1 ( f3 int(11), KEY (f3)) ;
INSERT INTO t1 VALUES (6),(4);
set @tmp_optimizer_switch=@@optimizer_switch;
set optimizer_switch='derived_merge=off,derived_with_keys=off';
EXPLAIN
SELECT * FROM (SELECT * FROM t2) AS a2
WHERE (SELECT distinct SUM(distinct f3 ) FROM t1);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY <derived2> system NULL NULL NULL NULL 0 Const row not found
3 SUBQUERY t1 index NULL f3 5 NULL 2 Using index
2 DERIVED NULL NULL NULL NULL NULL NULL NULL no matching row in const table
insert into t2 values (1),(2);
EXPLAIN
SELECT * FROM (SELECT * FROM t2) AS a2
WHERE (SELECT distinct SUM(distinct f3 ) FROM t1);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 2
3 SUBQUERY t1 index NULL f3 5 NULL 2 Using index
2 DERIVED t2 ALL NULL NULL NULL NULL 2
set optimizer_switch=@tmp_optimizer_switch;
drop table t1,t2;
#
# LP BUG#715027 Assertion `!table || (!table->read_set || bitmap_is_set(table->read_set, field_index))' failed
#
CREATE TABLE t1 ( f1 int(11), PRIMARY KEY (f1)) ;
INSERT INTO t1 VALUES (28),(29);
CREATE TABLE t2 ( f2 int(11), f3 int(11), f10 varchar(1)) ;
INSERT INTO t2 VALUES (NULL,6,'f'),(4,2,'d');
set @tmp_optimizer_switch=@@optimizer_switch;
set optimizer_switch='derived_merge=off,derived_with_keys=off';
EXPLAIN
SELECT alias2.f2 AS field1
FROM t1 AS alias1 JOIN ( SELECT * FROM t2 ) AS alias2 ON alias2.f3 = alias1.f1
WHERE (
SELECT t2.f2
FROM t2 JOIN t1 ON t1.f1
WHERE t1.f1 AND alias2.f10
)
ORDER BY field1 ;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 2 Using where; Using filesort
1 PRIMARY alias1 eq_ref PRIMARY PRIMARY 4 alias2.f3 1 Using index
3 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 2
3 DEPENDENT SUBQUERY t1 index PRIMARY PRIMARY 4 NULL 2 Using where; Using index; Using join buffer (flat, BNL join)
2 DERIVED t2 ALL NULL NULL NULL NULL 2
SELECT alias2.f2 AS field1
FROM t1 AS alias1 JOIN ( SELECT * FROM t2 ) AS alias2 ON alias2.f3 = alias1.f1
WHERE (
SELECT t2.f2
FROM t2 JOIN t1 ON t1.f1
WHERE t1.f1 AND alias2.f10
)
ORDER BY field1 ;
field1
Warnings:
Warning 1292 Truncated incorrect DOUBLE value: 'f'
Warning 1292 Truncated incorrect DOUBLE value: 'd'
set optimizer_switch=@tmp_optimizer_switch;
drop table t1,t2;
#
# LP BUG#718578 Yet another Assertion `!table ||
# (!table->read_set || bitmap_is_set(table->read_set, field_index))'
CREATE TABLE t1 ( f1 int(11), f2 int(11), f3 int(11)) ;
INSERT IGNORE INTO t1 VALUES (28,5,6),(29,NULL,4);
CREATE TABLE t2 ( f10 varchar(1) );
INSERT IGNORE INTO t2 VALUES (NULL);
SELECT f1 AS field1
FROM ( SELECT * FROM t1 ) AS alias1
WHERE (SELECT t1.f1
FROM t2 JOIN t1 ON t1.f2
WHERE alias1.f3 AND t1.f3) AND f2
ORDER BY field1;
field1
28
drop table t1,t2;
#
# LP BUG#601124 Bug in eliminate_item_equal
# leads to crash in Item_func::Item_func
CREATE TABLE t1 ( f1 int(11), f3 varchar(1)) ;
INSERT INTO t1 VALUES (5,'m'),(NULL,'c');
CREATE TABLE t2 ( f2 int(11), f3 varchar(1)) ;
INSERT INTO t2 VALUES (6,'f'),(2,'d');
CREATE TABLE t3 ( f2 int(11), f3 varchar(1)) ;
INSERT INTO t3 VALUES (6,'f'),(2,'d');
SELECT * FROM t3
WHERE ( f2 ) IN (SELECT t1.f1
FROM t1 STRAIGHT_JOIN t2 ON t2.f3 = t1.f3
WHERE t2.f3 = 'c');
f2 f3
drop table t1,t2,t3;
#
# LP BUG#718593 Crash in substitute_for_best_equal_field -> eliminate_item_equal ->
# Item_field::find_item_equal -> Item_equal::contains
#
set @save_optimizer_switch=@@optimizer_switch;
SET @@optimizer_switch = 'semijoin=off';
CREATE TABLE t1 ( f3 int(11), f10 varchar(1), f11 varchar(1)) ;
INSERT IGNORE INTO t1 VALUES (6,'f','f'),(2,'d','d');
CREATE TABLE t2 ( f12 int(11), f13 int(11)) ;
insert into t2 values (1,2), (3,4);
EXPLAIN
SELECT * FROM t2
WHERE ( f12 ) IN (
SELECT alias2.f3
FROM t1 AS alias1 JOIN t1 AS alias2 ON alias2.f10 = alias1.f11
WHERE alias1.f11 OR alias1.f3 = 50 AND alias1.f10
);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 2 Using where
2 MATERIALIZED alias1 ALL NULL NULL NULL NULL 2 Using where
2 MATERIALIZED alias2 ALL NULL NULL NULL NULL 2 Using where; Using join buffer (flat, BNL join)
SELECT * FROM t2
WHERE ( f12 ) IN (
SELECT alias2.f3
FROM t1 AS alias1 JOIN t1 AS alias2 ON alias2.f10 = alias1.f11
WHERE alias1.f11 OR alias1.f3 = 50 AND alias1.f10
);
f12 f13
Warnings:
Warning 1292 Truncated incorrect DOUBLE value: 'f'
Warning 1292 Truncated incorrect DOUBLE value: 'd'
EXPLAIN
SELECT * FROM t2
WHERE ( f12 ) IN (
SELECT alias2.f3
FROM t1 AS alias1, t1 AS alias2
WHERE (alias2.f10 = alias1.f11) AND (alias1.f11 OR alias1.f3 = 50 AND alias1.f10));
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 2 Using where
2 MATERIALIZED alias1 ALL NULL NULL NULL NULL 2 Using where
2 MATERIALIZED alias2 ALL NULL NULL NULL NULL 2 Using where; Using join buffer (flat, BNL join)
SELECT * FROM t2
WHERE ( f12 ) IN (
SELECT alias2.f3
FROM t1 AS alias1, t1 AS alias2
WHERE (alias2.f10 = alias1.f11) AND (alias1.f11 OR alias1.f3 = 50 AND alias1.f10));
f12 f13
Warnings:
Warning 1292 Truncated incorrect DOUBLE value: 'f'
Warning 1292 Truncated incorrect DOUBLE value: 'd'
set @@optimizer_switch=@save_optimizer_switch;
drop table t1, t2;
#
# MWL#89: test introduced after Sergey Petrunia's review - test that
# keyparts wihtout index prefix are used with the IN-EXISTS strategy.
#
create table t1 (c1 int);
insert into t1 values (1), (2), (3);
create table t2 (kp1 int, kp2 int, c2 int, filler char(100));
insert into t2 values (0,0,0,'filler'),(0,1,1,'filler'),(0,2,2,'filler'),(0,3,3,'filler');
create index key1 on t2 (kp1, kp2);
create index key2 on t2 (kp1);
create index key3 on t2 (kp2);
SET @@optimizer_switch='materialization=off,semijoin=off,in_to_exists=on';
analyze table t2;
Table Op Msg_type Msg_text
test.t2 analyze status Engine-independent statistics collected
test.t2 analyze status OK
explain
select c1 from t1 where c1 in (select kp1 from t2 where kp2 = 10 and c2 = 4) or c1 > 7;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3 Using where
2 DEPENDENT SUBQUERY t2 index_subquery key1,key2,key3 key1 10 func,const 1 Using where
select c1 from t1 where c1 in (select kp1 from t2 where kp2 = 10 and c2 = 4) or c1 > 7;
c1
set @@optimizer_switch='default';
drop table t1, t2;
#
# LP BUG#800679: Assertion `outer_join->table_count > 0' failed in
# JOIN::choose_subquery_plan() with materialization=on,semijoin=off
#
CREATE TABLE t1 ( f1 int);
insert into t1 values (1),(2);
CREATE TABLE t2 ( f1 int);
insert into t2 values (1),(2);
SET @@optimizer_switch='materialization=on,semijoin=off';
EXPLAIN
SELECT * FROM t1
WHERE (f1) IN (SELECT f1 FROM t2)
LIMIT 0;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY NULL NULL NULL NULL NULL NULL NULL Zero limit
2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 2 Using where
SELECT * FROM t1
WHERE (f1) IN (SELECT f1 FROM t2)
LIMIT 0;
f1
set @@optimizer_switch='default';
drop table t1, t2;
#
# LP BUG#834492: Crash in fix_semijoin_strategies_for_picked_join_order
# with nested subqueries and LooseScan=ON
#
CREATE TABLE t3 (b int) ;
INSERT INTO t3 VALUES (0),(0);
CREATE TABLE t4 (a int, b int, c int, d int, PRIMARY KEY (a)) ;
INSERT INTO t4 VALUES (28,0,0,0),(29,3,0,0);
CREATE TABLE t5 (a int, b int, c int, d int, KEY (c,b)) ;
INSERT INTO t5 VALUES (28,0,0,0),(29,3,0,0);
SET @@optimizer_switch='semijoin=ON,loosescan=ON,firstmatch=OFF,materialization=OFF';
EXPLAIN SELECT *
FROM t3
WHERE t3.b > ALL (
SELECT c
FROM t4
WHERE t4.a >= t3.b
AND a = SOME (SELECT b FROM t5));
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t3 ALL NULL NULL NULL NULL 2 Using where
2 DEPENDENT SUBQUERY t5 index c c 10 NULL 2 Using where; Using index; Start temporary
2 DEPENDENT SUBQUERY t4 eq_ref PRIMARY PRIMARY 4 test.t5.b 1 Using index condition; Using where; End temporary
SELECT *
FROM t3
WHERE t3.b > ALL (
SELECT c
FROM t4
WHERE t4.a >= t3.b
AND a = SOME (SELECT b FROM t5));
b
0
0
set @@optimizer_switch='default';
drop table t3, t4, t5;
#
# LP BUG#858038 The result of a query with NOT IN subquery depends on the state of the optimizer switch
#
set @optimizer_switch_save= @@optimizer_switch;
create table t1 (c1 char(2) not null, c2 char(2));
create table t2 (c3 char(2), c4 char(2));
insert into t1 values ('a1', 'b1');
insert into t1 values ('a2', 'b2');
insert into t2 values ('x1', 'y1');
insert into t2 values ('a2', null);
set @@optimizer_switch='in_to_exists=off,materialization=on,partial_match_rowid_merge=off,partial_match_table_scan=on';
explain select * from t1 where c1 = 'a2' and (c1, c2) not in (select * from t2);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 2 Using where
2 MATERIALIZED t2 ALL NULL NULL NULL NULL 2
select * from t1 where c1 = 'a2' and (c1, c2) not in (select * from t2);
c1 c2
set @@optimizer_switch='in_to_exists=off,materialization=on,partial_match_rowid_merge=on,partial_match_table_scan=off';
explain select * from t1 where c1 = 'a2' and (c1, c2) not in (select * from t2);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 2 Using where
2 MATERIALIZED t2 ALL NULL NULL NULL NULL 2
select * from t1 where c1 = 'a2' and (c1, c2) not in (select * from t2);
c1 c2
drop table t1, t2;
set optimizer_switch= @optimizer_switch_save;
#
# MDEV-12673: cost-based choice between materialization and in-to-exists
#
CREATE TABLE t1 (
pk1 int, a1 varchar(3), b1 varchar(3), PRIMARY KEY (pk1), KEY(a1), KEY(b1)
) ENGINE=MyISAM;
INSERT INTO t1 VALUES (1,'foo','bar'),(2,'bar','foo');
CREATE TABLE t2 (pk2 INT PRIMARY KEY, a2 VARCHAR(3), KEY(a2)) ENGINE=MyISAM;
INSERT INTO t2 VALUES (1,'abc'),(2,'xyz'),(3,'foo');
SELECT 'qux' IN ( SELECT a1 FROM t1 INNER JOIN t2 WHERE a2 = b1 AND pk2 = 3 );
'qux' IN ( SELECT a1 FROM t1 INNER JOIN t2 WHERE a2 = b1 AND pk2 = 3 )
0
SELECT 'bar' IN ( SELECT a1 FROM t1 INNER JOIN t2 WHERE a2 = b1 AND pk2 = 3 );
'bar' IN ( SELECT a1 FROM t1 INNER JOIN t2 WHERE a2 = b1 AND pk2 = 3 )
1
EXPLAIN
SELECT 'bar' IN ( SELECT a1 FROM t1 INNER JOIN t2 WHERE a2 = b1 AND pk2 = 3 );
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY NULL NULL NULL NULL NULL NULL NULL No tables used
2 SUBQUERY t2 const PRIMARY,a2 PRIMARY 4 const 1
2 SUBQUERY t1 ref a1,b1 b1 6 const 1 Using where
DROP TABLE t1,t2;
CREATE TABLE t1 (i1 INT) ENGINE=MyISAM;
INSERT INTO t1 VALUES (1);
CREATE TABLE t2 (i2 int, c2 varchar(3), KEY(i2,c2)) ENGINE=MyISAM;
INSERT INTO t2 VALUES (1,'abc'),(2,'foo');
CREATE TABLE t3 (pk3 int PRIMARY KEY, c3 varchar(3)) ENGINE=MyISAM;
INSERT INTO t3 VALUES (1,'foo'),(2,'bar');
SELECT * FROM t1 WHERE i1 NOT IN (
SELECT i2 FROM t2 RIGHT JOIN t3 ON (c3 = c2) WHERE pk3 = i1
);
i1
1
EXPLAIN
SELECT * FROM t1 WHERE i1 NOT IN (
SELECT i2 FROM t2 RIGHT JOIN t3 ON (c3 = c2) WHERE pk3 = i1
);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 system NULL NULL NULL NULL 1
2 DEPENDENT SUBQUERY t3 const PRIMARY PRIMARY 4 const 1
2 DEPENDENT SUBQUERY t2 index i2 i2 11 NULL 2 Using where; Using index
DROP TABLE t1,t2,t3;
#
# MDEV-7599: in-to-exists chosen after min/max optimization
#
set @optimizer_switch_save= @@optimizer_switch;
CREATE TABLE t1 (a INT, KEY(a)) ENGINE=MyISAM;
INSERT INTO t1 VALUES (1),(2);
CREATE TABLE t2 (b INT, c INT) ENGINE=MyISAM;
INSERT INTO t2 VALUES (1,6),(2,4), (8,9);
SELECT * FROM t2 WHERE b != ALL (SELECT MIN(a) FROM t1, t2 WHERE t2.c = t2.b);
b c
EXPLAIN EXTENDED SELECT * FROM t2 WHERE b != ALL (SELECT MIN(a) FROM t1, t2 WHERE t2.c = t2.b);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 3 100.00 Using where
2 MATERIALIZED t1 index NULL a 5 NULL 2 100.00 Using index
2 MATERIALIZED t2 ALL NULL NULL NULL NULL 3 100.00 Using where; Using join buffer (flat, BNL join)
Warnings:
Note 1003 /* select#1 */ select `test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t2` where !<expr_cache><`test`.`t2`.`b`>(<in_optimizer>(`test`.`t2`.`b`,`test`.`t2`.`b` in ( <materialize> (/* select#2 */ select min(`test`.`t1`.`a`) from `test`.`t1` join `test`.`t2` where `test`.`t2`.`c` = `test`.`t2`.`b` ), <primary_index_lookup>(`test`.`t2`.`b` in <temporary table> on distinct_key where `test`.`t2`.`b` = `<subquery2>`.`MIN(a)`))))
set optimizer_switch= 'materialization=off';
SELECT * FROM t2 WHERE b != ALL (SELECT MIN(a) FROM t1, t2 WHERE t2.c = t2.b);
b c
EXPLAIN EXTENDED SELECT * FROM t2 WHERE b != ALL (SELECT MIN(a) FROM t1, t2 WHERE t2.c = t2.b);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY t1 index NULL a 5 NULL 2 100.00 Using index
2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 3 100.00 Using where; Using join buffer (flat, BNL join)
Warnings:
Note 1003 /* select#1 */ select `test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t2` where !<expr_cache><`test`.`t2`.`b`>(<in_optimizer>(`test`.`t2`.`b`,<exists>(/* select#2 */ select min(`test`.`t1`.`a`) from `test`.`t1` join `test`.`t2` where `test`.`t2`.`c` = `test`.`t2`.`b` having trigcond(<cache>(`test`.`t2`.`b`) = <ref_null_helper>(min(`test`.`t1`.`a`))))))
set optimizer_switch= @optimizer_switch_save;
DROP TABLE t1,t2;
CREATE TABLE t1 (f1 varchar(10)) ENGINE=MyISAM;
INSERT INTO t1 VALUES ('foo'),('bar');
CREATE TABLE t2 (f2 varchar(10), key(f2)) ENGINE=MyISAM;
INSERT INTO t2 VALUES ('baz'),('qux');
CREATE TABLE t3 (f3 varchar(10)) ENGINE=MyISAM;
INSERT INTO t3 VALUES ('abc'),('def');
SELECT * FROM t1
WHERE f1 = ALL( SELECT MAX(t2a.f2)
FROM t2 AS t2a INNER JOIN t2 t2b INNER JOIN t3
ON (f3 = t2b.f2) );
f1
DROP TABLE t1,t2,t3;
#
# MDEV-12963: min/max optimization optimizing away all tables employed
# for uncorrelated IN subquery used in a disjunct of WHERE
#
create table t1 (a int, index idx(a)) engine=myisam;
insert into t1 values (4),(7),(1),(3),(9);
select * from t1 where a in (select max(a) from t1 where a < 4) or a > 5;
a
3
7
9
explain
select * from t1 where a in (select max(a) from t1 where a < 4) or a > 5;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 index idx idx 5 NULL 5 Using where; Using index
2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
drop table t1;
#
# MDEV-13135: subquery with ON expression subject to
# semi-join optimizations
#
CREATE TABLE t1 (a INT);
CREATE ALGORITHM=MERGE VIEW v1 AS SELECT a AS v_a FROM t1;
INSERT INTO t1 VALUES (1),(3);
CREATE TABLE t2 (b INT, KEY(b));
INSERT INTO t2 VALUES (3),(4);
SELECT * FROM t1 WHERE a NOT IN (
SELECT b FROM t2 INNER JOIN v1 ON (b IN ( SELECT a FROM t1 ))
WHERE v_a = b
);
a
1
DROP VIEW v1;
DROP TABLE t1,t2;
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