1 PRIMARY t1 ref a a 5 test.t0.a 1 100.00 Using where; FirstMatch(t2)
Warnings:
Note 1276 Field or reference 'test.t0.a' of SELECT #2 was resolved in SELECT #1
Note 1003 select `test`.`t0`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1`) join `test`.`t0` where ((`test`.`t1`.`b` = `test`.`t2`.`b`) and (`test`.`t2`.`a` = `test`.`t0`.`a`) and (`test`.`t1`.`a` = `test`.`t0`.`a`))
update t1 set a=3, b=11 where a=4;
update t2 set b=11 where a=3;
select * from t0 where t0.a in
(select t1.a from t1, t2 where t2.a=t0.a and t1.b=t2.b);
a
0
1
2
3
drop table t0, t1, t2;
CREATE TABLE t1 (
id int(11) NOT NULL,
PRIMARY KEY (id));
CREATE TABLE t2 (
id int(11) NOT NULL,
fid int(11) NOT NULL,
PRIMARY KEY (id));
insert into t1 values(1);
insert into t2 values(1,7503),(2,1);
explain select count(*)
from t1
where fid IN (select fid from t2 where (id between 7502 and 8420) order by fid );
ERROR 42S22: Unknown column 'fid' in 'IN/ALL/ANY subquery'
drop table t1, t2;
create table t1 (a int, b int, key (a), key (b));
insert into t1 values (2,4),(2,4),(2,4);
select t1.a from t1
where
t1.a in (select 1 from t1 where t1.a in (select 1 from t1) group by t1.a);
a
drop table t1;
create table t1(a int,b int,key(a),key(b));
insert into t1 values (1,1),(2,2),(3,3);
select 1 from t1
where t1.a not in (select 1 from t1
where t1.a in (select 1 from t1)
group by t1.b);
1
1
1
drop table t1;
CREATE TABLE t1
(EMPNUM CHAR(3) NOT NULL,
EMPNAME CHAR(20),
GRADE DECIMAL(4),
CITY CHAR(15));
CREATE TABLE t2
(PNUM CHAR(3) NOT NULL,
PNAME CHAR(20),
PTYPE CHAR(6),
BUDGET DECIMAL(9),
CITY CHAR(15));
CREATE TABLE t3
(EMPNUM CHAR(3) NOT NULL,
PNUM CHAR(3) NOT NULL,
HOURS DECIMAL(5));
INSERT INTO t1 VALUES ('E1','Alice',12,'Deale');
INSERT INTO t1 VALUES ('E2','Betty',10,'Vienna');
INSERT INTO t1 VALUES ('E3','Carmen',13,'Vienna');
INSERT INTO t1 VALUES ('E4','Don',12,'Deale');
INSERT INTO t1 VALUES ('E5','Ed',13,'Akron');
INSERT INTO t2 VALUES ('P1','MXSS','Design',10000,'Deale');
INSERT INTO t2 VALUES ('P2','CALM','Code',30000,'Vienna');
INSERT INTO t2 VALUES ('P3','SDP','Test',30000,'Tampa');
INSERT INTO t2 VALUES ('P4','SDP','Design',20000,'Deale');
INSERT INTO t2 VALUES ('P5','IRM','Test',10000,'Vienna');
INSERT INTO t2 VALUES ('P6','PAYR','Design',50000,'Deale');
INSERT INTO t3 VALUES ('E1','P1',40);
INSERT INTO t3 VALUES ('E1','P2',20);
INSERT INTO t3 VALUES ('E1','P3',80);
INSERT INTO t3 VALUES ('E1','P4',20);
INSERT INTO t3 VALUES ('E1','P5',12);
INSERT INTO t3 VALUES ('E1','P6',12);
INSERT INTO t3 VALUES ('E2','P1',40);
INSERT INTO t3 VALUES ('E2','P2',80);
INSERT INTO t3 VALUES ('E3','P2',20);
INSERT INTO t3 VALUES ('E4','P2',20);
INSERT INTO t3 VALUES ('E4','P4',40);
INSERT INTO t3 VALUES ('E4','P5',80);
SELECT * FROM t1;
EMPNUM EMPNAME GRADE CITY
E1 Alice 12 Deale
E2 Betty 10 Vienna
E3 Carmen 13 Vienna
E4 Don 12 Deale
E5 Ed 13 Akron
CREATE UNIQUE INDEX t1_IDX ON t1(EMPNUM);
SELECT EMPNAME
FROM t1
WHERE EMPNUM IN
(SELECT EMPNUM
FROM t3
WHERE PNUM IN
(SELECT PNUM
FROM t2
WHERE PTYPE = 'Design'));
EMPNAME
Alice
Betty
Don
DROP INDEX t1_IDX ON t1;
CREATE INDEX t1_IDX ON t1(EMPNUM);
SELECT EMPNAME
FROM t1
WHERE EMPNUM IN
(SELECT EMPNUM
FROM t3
WHERE PNUM IN
(SELECT PNUM
FROM t2
WHERE PTYPE = 'Design'));
EMPNAME
Alice
Betty
Don
DROP INDEX t1_IDX ON t1;
SELECT EMPNAME
FROM t1
WHERE EMPNUM IN
(SELECT EMPNUM
FROM t3
WHERE PNUM IN
(SELECT PNUM
FROM t2
WHERE PTYPE = 'Design'));
EMPNAME
Alice
Betty
Don
DROP TABLE t1, t2, t3;
CREATE TABLE t1 (f1 INT NOT NULL);
CREATE VIEW v1 (a) AS SELECT f1 IN (SELECT f1 FROM t1) FROM t1;
SELECT * FROM v1;
a
drop view v1;
drop table t1;
create table t0 (a int);
insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
create table t1(a int, b int);
insert into t1 values (0,0),(1,1),(2,2);
create table t2 as select * from t1;
create table t3 (pk int, a int, primary key(pk));
insert into t3 select a,a from t0;
explain
select * from t1 left join t2 on (t2.a= t1.a and t2.a in (select pk from t3));
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3
1 PRIMARY t2 ALL NULL NULL NULL NULL 3 Using where
2 SUBQUERY t3 index PRIMARY PRIMARY 4 NULL 10 Using index
drop table t0, t1, t2, t3;
create table t1 (a int);
insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
create table t2 (a char(200), b char(200), c char(200), primary key (a,b,c)) engine=innodb;
insert into t2 select concat(a, repeat('X',198)),repeat('B',200),repeat('B',200) from t1;
insert into t2 select concat(a, repeat('Y',198)),repeat('B',200),repeat('B',200) from t1;
alter table t2 add filler1 int;
insert into t1 select A.a + 10*(B.a + 10*C.a) from t1 A, t1 B, t1 C;
set @save_join_buffer_size=@@join_buffer_size;
set join_buffer_size=1;
select * from t2 where filler1 in ( select a from t1);
a b c filler1
set join_buffer_size=default;
drop table t1, t2;
create table t1 (a int not null);
drop procedure if exists p1;
CREATE PROCEDURE p1()
BEGIN
DECLARE EXIT HANDLER FOR SQLEXCEPTION select a from t1;
2 SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where; Using temporary
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from <materialize> (select `test`.`t2`.`b1` from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1`) join `test`.`t1` where (`<subquery2>`.`b1` = `test`.`t1`.`a1`)
select * from t1 where a1 in (select b1 from t2 where b1 > '0' group by b1);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1 where (a1, a2) in (select b1, b2 from t2 where b1 > '0' group by b1, b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
2 SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where; Using temporary
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from <materialize> (select `test`.`t2`.`b1`,`test`.`t2`.`b2` from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1`,`test`.`t2`.`b2`) join `test`.`t1` where ((`<subquery2>`.`b2` = `test`.`t1`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1`.`a1`))
select * from t1 where (a1, a2) in (select b1, b2 from t2 where b1 > '0' group by b1, b2);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
2 SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where; Using temporary
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from <materialize> (select `test`.`t2`.`b1`,min(`test`.`t2`.`b2`) from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1`) join `test`.`t1` where ((`<subquery2>`.`min(b2)` = `test`.`t1`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1`.`a1`))
select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1i where a1 in (select b1 from t2i where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2i index it2i1,it2i3 it2i1 # NULL 5 40.00 Using where; Using index; LooseScan
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` semi join (`test`.`t2i`) where ((`test`.`t1i`.`a1` = `test`.`t2i`.`b1`) and (`test`.`t2i`.`b1` > '0'))
select * from t1i where a1 in (select b1 from t2i where b1 > '0');
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1i where a1 in (select b1 from t2i where b1 > '0' group by b1);
id select_type table type possible_keys key key_len ref rows filtered Extra
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from <materialize> (select `test`.`t2i`.`b1` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1`) join `test`.`t1i` where (`test`.`t1i`.`a1` = `<subquery2>`.`b1`)
select * from t1i where a1 in (select b1 from t2i where b1 > '0' group by b1);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2i index it2i1,it2i2,it2i3 it2i3 # NULL 5 40.00 Using where; Using index; LooseScan
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` semi join (`test`.`t2i`) where ((`test`.`t1i`.`a2` = `test`.`t2i`.`b2`) and (`test`.`t1i`.`a1` = `test`.`t2i`.`b1`) and (`test`.`t2i`.`b1` > '0'))
select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0');
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0' group by b1, b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from <materialize> (select `test`.`t2i`.`b1`,`test`.`t2i`.`b2` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1`,`test`.`t2i`.`b2`) join `test`.`t1i` where ((`<subquery2>`.`b2` = `test`.`t1i`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1i`.`a1`))
select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0' group by b1, b2);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1i where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
id select_type table type possible_keys key key_len ref rows filtered Extra
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from <materialize> (select `test`.`t2i`.`b1`,min(`test`.`t2i`.`b2`) from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1`) join `test`.`t1i` where ((`<subquery2>`.`min(b2)` = `test`.`t1i`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1i`.`a1`))
select * from t1i where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
2 SUBQUERY t2i range NULL it2i3 9 NULL 3 100.00 Using index for group-by
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from <materialize> (select `test`.`t2i`.`b1`,max(`test`.`t2i`.`b2`) from `test`.`t2i` group by `test`.`t2i`.`b1`) join `test`.`t1` where ((`<subquery2>`.`max(b2)` = `test`.`t1`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1`.`a1`))
select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
prepare st1 from "explain select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1)";
execute st1;
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 SUBQUERY t2i range it2i1,it2i3 it2i3 18 NULL 3 100.00 Using where; Using index for group-by
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from <materialize> (select `test`.`t2i`.`b1`,min(`test`.`t2i`.`b2`) from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1`) join `test`.`t1` where ((`<subquery2>`.`min(b2)` = `test`.`t1`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1`.`a1`))
select * from t1 where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
select * from t1 where (a1, a2) in (select b1, min(b2) from t2i limit 1,1);
ERROR 42000: This version of MySQL doesn't yet support 'LIMIT & IN/ALL/ANY/SOME subquery'
set @save_optimizer_switch=@@optimizer_switch;
set @@optimizer_switch=@optimizer_switch_local_default;
set @@optimizer_switch='semijoin=off';
prepare st1 from
"select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1)";
set @@optimizer_switch=@optimizer_switch_local_default;
set @@optimizer_switch='materialization=off,in_to_exists=on';
execute st1;
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
set @@optimizer_switch=@optimizer_switch_local_default;
set @@optimizer_switch='semijoin=off';
execute st1;
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
set @@optimizer_switch=@optimizer_switch_local_default;
set @@optimizer_switch='materialization=off,in_to_exists=on';
prepare st1 from
"select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1)";
set @@optimizer_switch=@optimizer_switch_local_default;
set @@optimizer_switch='semijoin=off';
execute st1;
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
set @@optimizer_switch=@optimizer_switch_local_default;
set @@optimizer_switch='materialization=off,in_to_exists=on';
execute st1;
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
set @@optimizer_switch=@save_optimizer_switch;
explain extended
select * from t1 where (a1, a2) in (select b1, b2 from t2 order by b1, b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from <materialize> (select `test`.`t2`.`b1`,`test`.`t2`.`b2` from `test`.`t2` order by `test`.`t2`.`b1`,`test`.`t2`.`b2`) join `test`.`t1` where ((`<subquery2>`.`b2` = `test`.`t1`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1`.`a1`))
select * from t1 where (a1, a2) in (select b1, b2 from t2 order by b1, b2);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1i where (a1, a2) in (select b1, b2 from t2i order by b1, b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1i index it1i1,it1i2,it1i3 it1i3 18 NULL 3 100.00 Using where; Using index
2 SUBQUERY t2i index NULL it2i3 18 NULL 5 100.00 Using index
Warnings:
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from <materialize> (select `test`.`t2i`.`b1`,`test`.`t2i`.`b2` from `test`.`t2i` order by `test`.`t2i`.`b1`,`test`.`t2i`.`b2`) join `test`.`t1i` where ((`<subquery2>`.`b2` = `test`.`t1i`.`a2`) and (`<subquery2>`.`b1` = `test`.`t1i`.`a1`))
select * from t1i where (a1, a2) in (select b1, b2 from t2i order by b1, b2);
2 SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where
3 SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where
3 SUBQUERY t2i index it2i1,it2i2,it2i3 it2i3 18 NULL 5 80.00 Using where; Using index; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` semi join (`test`.`t2`) semi join (`test`.`t2i` join `test`.`t3`) where ((`test`.`t2i`.`b2` = `test`.`t3`.`c2`) and (`test`.`t2i`.`b1` = `test`.`t3`.`c1`) and (`test`.`t2`.`b1` > '0') and (`test`.`t3`.`c2` > '0'))
select * from t1
where (a1, a2) in (select b1, b2 from t2 where b1 > '0') and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1i
where (a1, a2) in (select b1, b2 from t2i where b1 > '0') and
(a1, a2) in (select c1, c2 from t3i
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
id select_type table type possible_keys key key_len ref rows filtered Extra
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` semi join (`test`.`t2i`) semi join (`test`.`t2i` join `test`.`t3i`) where ((`test`.`t3i`.`c2` = `test`.`t2i`.`b2`) and (`test`.`t3i`.`c1` = `test`.`t2i`.`b1`) and (`test`.`t2i`.`b1` > '0') and (`test`.`t2i`.`b2` > '0'))
select * from t1i
where (a1, a2) in (select b1, b2 from t2i where b1 > '0') and
(a1, a2) in (select c1, c2 from t3i
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1
where (a1, a2) in (select b1, b2 from t2
where b2 in (select c2 from t3 where c2 LIKE '%02') or
b2 in (select c2 from t3 where c2 LIKE '%03')) and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
id select_type table type possible_keys key key_len ref rows filtered Extra
2 SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where
5 SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where
5 SUBQUERY t2i index it2i1,it2i2,it2i3 it2i3 18 NULL 5 80.00 Using where; Using index; Using join buffer (flat, BNL join)
4 SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where
3 SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` semi join (`test`.`t2`) semi join (`test`.`t2i` join `test`.`t3`) where ((`test`.`t2i`.`b2` = `test`.`t3`.`c2`) and (`test`.`t2i`.`b1` = `test`.`t3`.`c1`) and (<expr_cache><`test`.`t2`.`b2`>(<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%02') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `<subquery3>`.`c2`)))))) or <expr_cache><`test`.`t2`.`b2`>(<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `<subquery4>`.`c2`))))))) and (`test`.`t3`.`c2` > '0'))
select * from t1
where (a1, a2) in (select b1, b2 from t2
where b2 in (select c2 from t3 where c2 LIKE '%02') or
b2 in (select c2 from t3 where c2 LIKE '%03')) and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
a1 a2
1 - 02 2 - 02
explain extended
select * from t1
where (a1, a2) in (select b1, b2 from t2
where b2 in (select c2 from t3 t3a where c1 = a1) or
b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and
(a1, a2) in (select c1, c2 from t3 t3c
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
id select_type table type possible_keys key key_len ref rows filtered Extra
5 SUBQUERY t3c ALL NULL NULL NULL NULL 4 100.00 Using where
5 SUBQUERY t2i index it2i1,it2i2,it2i3 it2i3 18 NULL 5 80.00 Using where; Using index; Using join buffer (flat, BNL join)
4 SUBQUERY t3b ALL NULL NULL NULL NULL 4 100.00 Using where
3 DEPENDENT SUBQUERY t3a ALL NULL NULL NULL NULL 4 100.00 Using where
Warnings:
Note 1276 Field or reference 'test.t1.a1' of SELECT #3 was resolved in SELECT #1
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` semi join (`test`.`t2`) semi join (`test`.`t2i` join `test`.`t3` `t3c`) where ((`test`.`t2`.`b2` = `test`.`t1`.`a2`) and (`test`.`t2i`.`b2` = `test`.`t3c`.`c2`) and (`test`.`t2`.`b1` = `test`.`t1`.`a1`) and (`test`.`t2i`.`b1` = `test`.`t3c`.`c1`) and (<expr_cache><`test`.`t2`.`b2`,`test`.`t1`.`a1`>(<in_optimizer>(`test`.`t2`.`b2`,<exists>(select `test`.`t3a`.`c2` from `test`.`t3` `t3a` where ((`test`.`t3a`.`c1` = `test`.`t1`.`a1`) and (<cache>(`test`.`t2`.`b2`) = `test`.`t3a`.`c2`))))) or <expr_cache><`test`.`t2`.`b2`>(<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3b`.`c2` from `test`.`t3` `t3b` where (`test`.`t3b`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `<subquery4>`.`c2`))))))) and (`test`.`t3c`.`c2` > '0'))
select * from t1
where (a1, a2) in (select b1, b2 from t2
where b2 in (select c2 from t3 t3a where c1 = a1) or
b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and
(a1, a2) in (select c1, c2 from t3 t3c
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
(select * from t1
where (a1, a2) in (select b1, b2 from t2
where b2 in (select c2 from t3 where c2 LIKE '%02') or
b2 in (select c2 from t3 where c2 LIKE '%03')
group by b1, b2) and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0')))
UNION
(select * from t1i
where (a1, a2) in (select b1, b2 from t2i where b1 > '0') and
(a1, a2) in (select c1, c2 from t3i
where (c1, c2) in (select b1, b2 from t2i where b2 > '0')));
id select_type table type possible_keys key key_len ref rows filtered Extra
NULL UNION RESULT <union1,7> ALL NULL # # # NULL NULL #
Warnings:
Note 1003 (select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from <materialize> (select `test`.`t2`.`b1`,`test`.`t2`.`b2` from `test`.`t2` where (<expr_cache><`test`.`t2`.`b2`>(<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%02') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `<subquery3>`.`c2`)))))) or <expr_cache><`test`.`t2`.`b2`>(<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `<subquery4>`.`c2`))))))) group by `test`.`t2`.`b1`,`test`.`t2`.`b2`) semi join (`test`.`t2i` join `test`.`t3`) join `test`.`t1` where ((`test`.`t3`.`c2` = `<subquery2>`.`b2`) and (`test`.`t1`.`a2` = `<subquery2>`.`b2`) and (`test`.`t2i`.`b2` = `<subquery2>`.`b2`) and (`test`.`t3`.`c1` = `<subquery2>`.`b1`) and (`test`.`t1`.`a1` = `<subquery2>`.`b1`) and (`test`.`t2i`.`b1` = `<subquery2>`.`b1`) and (`<subquery2>`.`b2` > '0'))) union (select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` semi join (`test`.`t2i`) semi join (`test`.`t2i` join `test`.`t3i`) where ((`test`.`t3i`.`c2` = `test`.`t2i`.`b2`) and (`test`.`t3i`.`c1` = `test`.`t2i`.`b1`) and (`test`.`t2i`.`b1` > '0') and (`test`.`t2i`.`b2` > '0')))
(select * from t1
where (a1, a2) in (select b1, b2 from t2
where b2 in (select c2 from t3 where c2 LIKE '%02') or
b2 in (select c2 from t3 where c2 LIKE '%03')
group by b1, b2) and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0')))
UNION
(select * from t1i
where (a1, a2) in (select b1, b2 from t2i where b1 > '0') and
(a1, a2) in (select c1, c2 from t3i
where (c1, c2) in (select b1, b2 from t2i where b2 > '0')));
a1 a2
1 - 02 2 - 02
1 - 01 2 - 01
explain extended
select * from t1
where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
4 SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where
4 SUBQUERY t2i index it2i1,it2i2,it2i3 it2i3 18 NULL 5 80.00 Using where; Using index; Using join buffer (flat, BNL join)
2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
3 DEPENDENT UNION t2 ALL NULL NULL NULL NULL 5 100.00 Using where
NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL NULL NULL
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` semi join (`test`.`t2i` join `test`.`t3`) where ((`test`.`t2i`.`b2` = `test`.`t3`.`c2`) and (`test`.`t2i`.`b1` = `test`.`t3`.`c1`) and <expr_cache><`test`.`t1`.`a1`,`test`.`t1`.`a2`>(<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t1`.`a1`,`test`.`t1`.`a2` from `test`.`t1` where ((`test`.`t1`.`a1` > '0') and (<cache>(`test`.`t1`.`a1`) = `test`.`t1`.`a1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t1`.`a2`)) union select `test`.`t2`.`b1`,`test`.`t2`.`b2` from `test`.`t2` where ((`test`.`t2`.`b1` < '9') and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`b1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t2`.`b2`))))) and (`test`.`t3`.`c2` > '0'))
select * from t1
where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1, t3
where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
(c1, c2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0')) and
a1 = c1;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
1 PRIMARY t3 ALL NULL NULL NULL NULL 4 100.00 Using where; Using join buffer (flat, BNL join)
4 SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where
4 SUBQUERY t2i index it2i1,it2i2,it2i3 it2i3 18 NULL 5 80.00 Using where; Using index; Using join buffer (flat, BNL join)
2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
3 DEPENDENT UNION t2 ALL NULL NULL NULL NULL 5 100.00 Using where
NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL NULL NULL
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2`,`test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t1` semi join (`test`.`t2i` join `test`.`t3`) join `test`.`t3` where ((`test`.`t2i`.`b2` = `test`.`t3`.`c2`) and (`test`.`t3`.`c1` = `test`.`t1`.`a1`) and (`test`.`t2i`.`b1` = `test`.`t3`.`c1`) and <expr_cache><`test`.`t1`.`a1`,`test`.`t1`.`a2`>(<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t1`.`a1`,`test`.`t1`.`a2` from `test`.`t1` where ((`test`.`t1`.`a1` > '0') and (<cache>(`test`.`t1`.`a1`) = `test`.`t1`.`a1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t1`.`a2`)) union select `test`.`t2`.`b1`,`test`.`t2`.`b2` from `test`.`t2` where ((`test`.`t2`.`b1` < '9') and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`b1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t2`.`b2`))))) and (`test`.`t3`.`c2` > '0'))
select * from t1, t3
where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
(c1, c2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0')) and
where c1 in (select a1 from t1 where a1 > '0' UNION select b1 from t2 where b1 < '9');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t3 ALL NULL NULL NULL NULL 4 100.00 Using where
2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
3 DEPENDENT UNION t2 ALL NULL NULL NULL NULL 5 100.00 Using where
NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL NULL NULL
Warnings:
Note 1003 select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t3` where <expr_cache><`test`.`t3`.`c1`>(<in_optimizer>(`test`.`t3`.`c1`,<exists>(select `test`.`t1`.`a1` from `test`.`t1` where ((`test`.`t1`.`a1` > '0') and (<cache>(`test`.`t3`.`c1`) = `test`.`t1`.`a1`)) union select `test`.`t2`.`b1` from `test`.`t2` where ((`test`.`t2`.`b1` < '9') and (<cache>(`test`.`t3`.`c1`) = `test`.`t2`.`b1`)))))
select * from t3
where c1 in (select a1 from t1 where a1 > '0' UNION select b1 from t2 where b1 < '9');
c1 c2
1 - 01 2 - 01
1 - 02 2 - 02
1 - 03 2 - 03
explain extended
select * from t1
where (a1, a2) in (select b1, b2 from t2
where b2 in (select c2 from t3 t3a where c1 = a1) or
b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and
(a1, a2) in (select c1, c2 from t3 t3c
where (c1, c2) in (select b1, b2 from t2i where b2 > '0' or b2 = a2));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary
1 PRIMARY t2i ref it2i1,it2i2,it2i3 it2i3 18 test.t1.a1,test.t1.a2 2 100.00 Using index
1 PRIMARY t2 ALL NULL NULL NULL NULL 5 100.00 Using where; Using join buffer (flat, BNL join)
1 PRIMARY t3c ALL NULL NULL NULL NULL 4 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
4 SUBQUERY t3b ALL NULL NULL NULL NULL 4 100.00 Using where
3 DEPENDENT SUBQUERY t3a ALL NULL NULL NULL NULL 4 100.00 Using where
Warnings:
Note 1276 Field or reference 'test.t1.a1' of SELECT #3 was resolved in SELECT #1
Note 1276 Field or reference 'test.t1.a2' of SELECT #6 was resolved in SELECT #1
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` semi join (`test`.`t2`) semi join (`test`.`t2i` join `test`.`t3` `t3c`) where ((`test`.`t2i`.`b2` = `test`.`t1`.`a2`) and (`test`.`t2`.`b2` = `test`.`t1`.`a2`) and (`test`.`t3c`.`c2` = `test`.`t1`.`a2`) and (`test`.`t2i`.`b1` = `test`.`t1`.`a1`) and (`test`.`t2`.`b1` = `test`.`t1`.`a1`) and (`test`.`t3c`.`c1` = `test`.`t1`.`a1`) and (<expr_cache><`test`.`t2`.`b2`,`test`.`t1`.`a1`>(<in_optimizer>(`test`.`t2`.`b2`,<exists>(select `test`.`t3a`.`c2` from `test`.`t3` `t3a` where ((`test`.`t3a`.`c1` = `test`.`t1`.`a1`) and (<cache>(`test`.`t2`.`b2`) = `test`.`t3a`.`c2`))))) or <expr_cache><`test`.`t2`.`b2`>(<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3b`.`c2` from `test`.`t3` `t3b` where (`test`.`t3b`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `<subquery4>`.`c2`))))))))
explain extended
select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <expr_cache><`test`.`t1`.`a1`,`test`.`t1`.`a2`>(<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select '1 - 01','2 - 01' having (((<cache>(`test`.`t1`.`a1`) = '1 - 01') or isnull('1 - 01')) and ((<cache>(`test`.`t1`.`a2`) = '2 - 01') or isnull('2 - 01')) and <is_not_null_test>('1 - 01') and <is_not_null_test>('2 - 01')))))
select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01');
a1 a2
1 - 01 2 - 01
explain extended
select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01' from dual);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <expr_cache><`test`.`t1`.`a1`,`test`.`t1`.`a2`>(<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select '1 - 01','2 - 01' having (((<cache>(`test`.`t1`.`a1`) = '1 - 01') or isnull('1 - 01')) and ((<cache>(`test`.`t1`.`a2`) = '2 - 01') or isnull('2 - 01')) and <is_not_null_test>('1 - 01') and <is_not_null_test>('2 - 01')))))
select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01' from dual);
select ((a1,a2) IN (select * from t2 where b2 > '0')) IS NULL from t1;
((a1,a2) IN (select * from t2 where b2 > '0')) IS NULL
0
0
0
/* GROUP BY clause */
create table columns (col int key);
insert into columns values (1), (2);
explain extended
select * from t1 group by (select col from columns limit 1);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00
2 SUBQUERY columns index NULL PRIMARY 4 NULL 2 100.00 Using index
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` group by (select `test`.`columns`.`col` from `test`.`columns` limit 1)
select * from t1 group by (select col from columns limit 1);
a1 a2
1 - 00 2 - 00
explain extended
select * from t1 group by (a1 in (select col from columns));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using temporary; Using filesort
2 DEPENDENT SUBQUERY columns unique_subquery PRIMARY PRIMARY 4 func 1 100.00 Using index; Using where; Full scan on NULL key
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` group by <expr_cache><`test`.`t1`.`a1`>(<in_optimizer>(`test`.`t1`.`a1`,<exists>(<primary_index_lookup>(<cache>(`test`.`t1`.`a1`) in columns on PRIMARY where trigcond((<cache>(`test`.`t1`.`a1`) = `test`.`columns`.`col`))))))
select * from t1 group by (a1 in (select col from columns));
a1 a2
1 - 00 2 - 00
/* ORDER BY clause */
explain extended
select * from t1 order by (select col from columns limit 1);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00
2 SUBQUERY columns index NULL PRIMARY 4 NULL 2 100.00 Using index
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` order by (select `test`.`columns`.`col` from `test`.`columns` limit 1)
select * from t1 order by (select col from columns limit 1);
where a1 in (select b1 from t2_16 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary
1 PRIMARY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` semi join (`test`.`t2_16`) where ((`test`.`t2_16`.`b1` = `test`.`t1_16`.`a1`) and (`test`.`t1_16`.`a1` > '0'))
select left(a1,7), left(a2,7)
from t1_16
where a1 in (select b1 from t2_16 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_16
where (a1,a2) in (select b1, b2 from t2_16 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary
1 PRIMARY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` semi join (`test`.`t2_16`) where ((`test`.`t2_16`.`b2` = `test`.`t1_16`.`a2`) and (`test`.`t2_16`.`b1` = `test`.`t1_16`.`a1`) and (`test`.`t1_16`.`a1` > '0'))
select left(a1,7), left(a2,7)
from t1_16
where (a1,a2) in (select b1, b2 from t2_16 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_16
where a1 in (select substring(b1,1,16) from t2_16 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
2 SUBQUERY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` semi join (`test`.`t2_16`) where ((`test`.`t2_16`.`b1` > '0') and (`test`.`t1_16`.`a1` = substr(`test`.`t2_16`.`b1`,1,16)))
select left(a1,7), left(a2,7)
from t1_16
where a1 in (select substring(b1,1,16) from t2_16 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_16
where a1 in (select group_concat(b1) from t2_16 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` where <expr_cache><`test`.`t1_16`.`a1`>(<in_optimizer>(`test`.`t1_16`.`a1`,<exists>(select group_concat(`test`.`t2_16`.`b1` separator ',') from `test`.`t2_16` group by `test`.`t2_16`.`b2` having (<cache>(`test`.`t1_16`.`a1`) = <ref_null_helper>(group_concat(`test`.`t2_16`.`b1` separator ','))))))
select left(a1,7), left(a2,7)
from t1_16
where a1 in (select group_concat(b1) from t2_16 group by b2);
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
set @@group_concat_max_len = 256;
explain extended select left(a1,7), left(a2,7)
from t1_16
where a1 in (select group_concat(b1) from t2_16 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where
1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 261 test.t1_16.a1 1 100.00 Using where
2 SUBQUERY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from <materialize> (select group_concat(`test`.`t2_16`.`b1` separator ',') from `test`.`t2_16` group by `test`.`t2_16`.`b2`) join `test`.`t1_16` where (`test`.`t1_16`.`a1` = `<subquery2>`.`group_concat(b1)`)
select left(a1,7), left(a2,7)
from t1_16
where a1 in (select group_concat(b1) from t2_16 group by b2);
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended
select * from t1
where concat(a1,'x') IN
(select left(a1,8) from t1_16
where (a1, a2) IN
(select t2_16.b1, t2_16.b2 from t2_16, t2
where t2.b2 = substring(t2_16.b2,1,6) and
t2.b1 IN (select c1 from t3 where c2 > '0')));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where; Using join buffer (flat, BNL join)
1 PRIMARY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using where; Using join buffer (flat, BNL join)
1 PRIMARY t3 ALL NULL NULL NULL NULL 4 100.00 Using where; Using join buffer (flat, BNL join)
1 PRIMARY t2 ALL NULL NULL NULL NULL 5 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` semi join (`test`.`t3` join `test`.`t2_16` join `test`.`t2` join `test`.`t1_16`) where ((`test`.`t2_16`.`b2` = `test`.`t1_16`.`a2`) and (`test`.`t2_16`.`b1` = `test`.`t1_16`.`a1`) and (`test`.`t2`.`b1` = `test`.`t3`.`c1`) and (`test`.`t2`.`b2` = substr(`test`.`t1_16`.`a2`,1,6)) and (`test`.`t3`.`c2` > '0') and (concat(`test`.`t1`.`a1`,'x') = left(`test`.`t1_16`.`a1`,8)))
where a1 in (select b1 from t2_512 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_512 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary
1 PRIMARY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from `test`.`t1_512` semi join (`test`.`t2_512`) where ((`test`.`t2_512`.`b1` = `test`.`t1_512`.`a1`) and (`test`.`t1_512`.`a1` > '0'))
select left(a1,7), left(a2,7)
from t1_512
where a1 in (select b1 from t2_512 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_512
where (a1,a2) in (select b1, b2 from t2_512 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_512 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary
1 PRIMARY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from `test`.`t1_512` semi join (`test`.`t2_512`) where ((`test`.`t2_512`.`b2` = `test`.`t1_512`.`a2`) and (`test`.`t2_512`.`b1` = `test`.`t1_512`.`a1`) and (`test`.`t1_512`.`a1` > '0'))
select left(a1,7), left(a2,7)
from t1_512
where (a1,a2) in (select b1, b2 from t2_512 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_512
where a1 in (select substring(b1,1,512) from t2_512 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
2 SUBQUERY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from `test`.`t1_512` semi join (`test`.`t2_512`) where ((`test`.`t2_512`.`b1` > '0') and (`test`.`t1_512`.`a1` = substr(`test`.`t2_512`.`b1`,1,512)))
select left(a1,7), left(a2,7)
from t1_512
where a1 in (select substring(b1,1,512) from t2_512 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_512
where a1 in (select group_concat(b1) from t2_512 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_512 ALL NULL NULL NULL NULL 3 100.00 Using where
1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 261 test.t1_512.a1 1 100.00 Using where
2 SUBQUERY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from <materialize> (select group_concat(`test`.`t2_512`.`b1` separator ',') from `test`.`t2_512` group by `test`.`t2_512`.`b2`) join `test`.`t1_512` where (`test`.`t1_512`.`a1` = `<subquery2>`.`group_concat(b1)`)
select left(a1,7), left(a2,7)
from t1_512
where a1 in (select group_concat(b1) from t2_512 group by b2);
left(a1,7) left(a2,7)
set @@group_concat_max_len = 256;
explain extended select left(a1,7), left(a2,7)
from t1_512
where a1 in (select group_concat(b1) from t2_512 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_512 ALL NULL NULL NULL NULL 3 100.00 Using where
1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 261 test.t1_512.a1 1 100.00 Using where
2 SUBQUERY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from <materialize> (select group_concat(`test`.`t2_512`.`b1` separator ',') from `test`.`t2_512` group by `test`.`t2_512`.`b2`) join `test`.`t1_512` where (`test`.`t1_512`.`a1` = `<subquery2>`.`group_concat(b1)`)
select left(a1,7), left(a2,7)
from t1_512
where a1 in (select group_concat(b1) from t2_512 group by b2);
where a1 in (select b1 from t2_1024 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary
1 PRIMARY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` semi join (`test`.`t2_1024`) where ((`test`.`t2_1024`.`b1` = `test`.`t1_1024`.`a1`) and (`test`.`t1_1024`.`a1` > '0'))
select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select b1 from t2_1024 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_1024
where (a1,a2) in (select b1, b2 from t2_1024 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary
1 PRIMARY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` semi join (`test`.`t2_1024`) where ((`test`.`t2_1024`.`b2` = `test`.`t1_1024`.`a2`) and (`test`.`t2_1024`.`b1` = `test`.`t1_1024`.`a1`) and (`test`.`t1_1024`.`a1` > '0'))
select left(a1,7), left(a2,7)
from t1_1024
where (a1,a2) in (select b1, b2 from t2_1024 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select substring(b1,1,1024) from t2_1024 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` semi join (`test`.`t2_1024`) where ((`test`.`t2_1024`.`b1` > '0') and (`test`.`t1_1024`.`a1` = substr(`test`.`t2_1024`.`b1`,1,1024)))
select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select substring(b1,1,1024) from t2_1024 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select group_concat(b1) from t2_1024 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 100.00 Using where
1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 261 test.t1_1024.a1 1 100.00 Using where
2 SUBQUERY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from <materialize> (select group_concat(`test`.`t2_1024`.`b1` separator ',') from `test`.`t2_1024` group by `test`.`t2_1024`.`b2`) join `test`.`t1_1024` where (`test`.`t1_1024`.`a1` = `<subquery2>`.`group_concat(b1)`)
select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select group_concat(b1) from t2_1024 group by b2);
left(a1,7) left(a2,7)
set @@group_concat_max_len = 256;
explain extended select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select group_concat(b1) from t2_1024 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 100.00 Using where
1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 261 test.t1_1024.a1 1 100.00 Using where
2 SUBQUERY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from <materialize> (select group_concat(`test`.`t2_1024`.`b1` separator ',') from `test`.`t2_1024` group by `test`.`t2_1024`.`b2`) join `test`.`t1_1024` where (`test`.`t1_1024`.`a1` = `<subquery2>`.`group_concat(b1)`)
select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select group_concat(b1) from t2_1024 group by b2);
where a1 in (select b1 from t2_1025 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1025 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary
1 PRIMARY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` semi join (`test`.`t2_1025`) where ((`test`.`t2_1025`.`b1` = `test`.`t1_1025`.`a1`) and (`test`.`t1_1025`.`a1` > '0'))
select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select b1 from t2_1025 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_1025
where (a1,a2) in (select b1, b2 from t2_1025 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1025 ALL NULL NULL NULL NULL 3 100.00 Using where; Start temporary
1 PRIMARY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` semi join (`test`.`t2_1025`) where ((`test`.`t2_1025`.`b2` = `test`.`t1_1025`.`a2`) and (`test`.`t2_1025`.`b1` = `test`.`t1_1025`.`a1`) and (`test`.`t1_1025`.`a1` > '0'))
select left(a1,7), left(a2,7)
from t1_1025
where (a1,a2) in (select b1, b2 from t2_1025 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select substring(b1,1,1025) from t2_1025 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` semi join (`test`.`t2_1025`) where ((`test`.`t2_1025`.`b1` > '0') and (`test`.`t1_1025`.`a1` = substr(`test`.`t2_1025`.`b1`,1,1025)))
select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select substring(b1,1,1025) from t2_1025 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select group_concat(b1) from t2_1025 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1025 ALL NULL NULL NULL NULL 3 100.00 Using where
1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 261 test.t1_1025.a1 1 100.00 Using where
2 SUBQUERY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from <materialize> (select group_concat(`test`.`t2_1025`.`b1` separator ',') from `test`.`t2_1025` group by `test`.`t2_1025`.`b2`) join `test`.`t1_1025` where (`test`.`t1_1025`.`a1` = `<subquery2>`.`group_concat(b1)`)
select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select group_concat(b1) from t2_1025 group by b2);
left(a1,7) left(a2,7)
set @@group_concat_max_len = 256;
explain extended select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select group_concat(b1) from t2_1025 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1025 ALL NULL NULL NULL NULL 3 100.00 Using where
1 PRIMARY <subquery2> eq_ref distinct_key distinct_key 261 test.t1_1025.a1 1 100.00 Using where
2 SUBQUERY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from <materialize> (select group_concat(`test`.`t2_1025`.`b1` separator ',') from `test`.`t2_1025` group by `test`.`t2_1025`.`b2`) join `test`.`t1_1025` where (`test`.`t1_1025`.`a1` = `<subquery2>`.`group_concat(b1)`)
select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select group_concat(b1) from t2_1025 group by b2);
left(a1,7) left(a2,7)
drop table t1_1025, t2_1025, t3_1025;
create table t1bit (a1 bit(3), a2 bit(3));
create table t2bit (b1 bit(3), b2 bit(3));
insert into t1bit values (b'000', b'100');
insert into t1bit values (b'001', b'101');
insert into t1bit values (b'010', b'110');
insert into t2bit values (b'001', b'101');
insert into t2bit values (b'010', b'110');
insert into t2bit values (b'110', b'111');
explain extended select bin(a1), bin(a2)
from t1bit
where (a1, a2) in (select b1, b2 from t2bit);
id select_type table type possible_keys key key_len ref rows filtered Extra
Note 1003 select conv(`test`.`t1bit`.`a1`,10,2) AS `bin(a1)`,conv(`test`.`t1bit`.`a2`,10,2) AS `bin(a2)` from `test`.`t1bit` semi join (`test`.`t2bit`) where 1
select bin(a1), bin(a2)
from t1bit
where (a1, a2) in (select b1, b2 from t2bit);
bin(a1) bin(a2)
1 101
10 110
drop table t1bit, t2bit;
create table t1bb (a1 bit(3), a2 blob(3));
create table t2bb (b1 bit(3), b2 blob(3));
insert into t1bb values (b'000', '100');
insert into t1bb values (b'001', '101');
insert into t1bb values (b'010', '110');
insert into t2bb values (b'001', '101');
insert into t2bb values (b'010', '110');
insert into t2bb values (b'110', '111');
explain extended select bin(a1), a2
from t1bb
where (a1, a2) in (select b1, b2 from t2bb);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2bb ALL NULL NULL NULL NULL 3 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select conv(`test`.`t1bb`.`a1`,10,2) AS `bin(a1)`,`test`.`t1bb`.`a2` AS `a2` from `test`.`t1bb` semi join (`test`.`t2bb`) where ((`test`.`t2bb`.`b2` = `test`.`t1bb`.`a2`) and (`test`.`t2bb`.`b1` = `test`.`t1bb`.`a1`))
# Test that default values of Cached_item are not used for comparison
create table t1 (s1 int);
create table t2 (s2 int);
insert into t1 values (5),(1),(0);
insert into t2 values (0), (1);
select s2 from t2 where s2 in (select s1 from t1);
s2
0
1
drop table t1, t2;
create table t1 (a int not null, b int not null);
create table t2 (c int not null, d int not null);
create table t3 (e int not null);
insert into t1 values (1,10);
insert into t1 values (1,20);
insert into t1 values (2,10);
insert into t1 values (2,20);
insert into t1 values (2,30);
insert into t1 values (3,20);
insert into t1 values (4,40);
insert into t2 values (2,10);
insert into t2 values (2,20);
insert into t2 values (2,40);
insert into t2 values (3,20);
insert into t2 values (4,10);
insert into t2 values (5,10);
insert into t3 values (10);
insert into t3 values (10);
insert into t3 values (20);
insert into t3 values (30);
explain extended
select a from t1 where a in (select c from t2 where d >= 20);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY <subquery2> ALL distinct_key NULL NULL NULL 6 100.00
1 PRIMARY t1 ALL NULL NULL NULL NULL 7 100.00 Using where; Using join buffer (flat, BNL join)
2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t1`.`a` = `test`.`t2`.`c`) and (`test`.`t2`.`d` >= 20))
select a from t1 where a in (select c from t2 where d >= 20);
a
2
2
2
3
create index it1a on t1(a);
explain extended
select a from t1 where a in (select c from t2 where d >= 20);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY <subquery2> ALL distinct_key NULL NULL NULL 6 100.00
1 PRIMARY t1 ref it1a it1a 4 test.t2.c 2 100.00 Using index
2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t1`.`a` = `test`.`t2`.`c`) and (`test`.`t2`.`d` >= 20))
select a from t1 where a in (select c from t2 where d >= 20);
a
2
2
2
3
insert into t2 values (1,10);
explain extended
select a from t1 where a in (select c from t2 where d >= 20);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 index it1a it1a 4 NULL 7 100.00 Using index
2 SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t2`.`d` >= 20))
select a from t1 where a in (select c from t2 where d >= 20);
a
2
2
2
3
explain extended
select a from t1 group by a having a in (select c from t2 where d >= 20);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 index NULL it1a 4 NULL 7 100.00 Using index
2 SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <expr_cache><`test`.`t1`.`a`>(<in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (select `test`.`t2`.`c` from `test`.`t2` where (`test`.`t2`.`d` >= 20) ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key where ((`test`.`t1`.`a` = `<subquery2>`.`c`))))))
select a from t1 group by a having a in (select c from t2 where d >= 20);
a
2
3
create index iab on t1(a, b);
explain extended
select a from t1 group by a having a in (select c from t2 where d >= 20);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 index NULL it1a 4 NULL 7 100.00 Using index
2 SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <expr_cache><`test`.`t1`.`a`>(<in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (select `test`.`t2`.`c` from `test`.`t2` where (`test`.`t2`.`d` >= 20) ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key where ((`test`.`t1`.`a` = `<subquery2>`.`c`))))))
select a from t1 group by a having a in (select c from t2 where d >= 20);
a
2
3
explain extended
select a from t1 group by a
having a in (select c from t2 where d >= some(select e from t3 where max(b)=e));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 index NULL iab 8 NULL 7 100.00 Using index
2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where
3 DEPENDENT SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where
Warnings:
Note 1276 Field or reference 'test.t1.b' of SELECT #3 was resolved in SELECT #1
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <expr_cache><`test`.`t1`.`a`,`test`.`t1`.`b`,max(`test`.`t1`.`b`),max(`test`.`t1`.`b`)>(<in_optimizer>(`test`.`t1`.`a`,<exists>(select `test`.`t2`.`c` from `test`.`t2` where (<nop>(<expr_cache><`test`.`t2`.`d`,`test`.`t1`.`b`,max(`test`.`t1`.`b`),max(`test`.`t1`.`b`)>(<in_optimizer>(`test`.`t2`.`d`,<exists>(select `test`.`t3`.`e` from `test`.`t3` where (max(`test`.`t1`.`b`) = `test`.`t3`.`e`) having (<cache>(`test`.`t2`.`d`) >= <ref_null_helper>(`test`.`t3`.`e`)))))) and (<cache>(`test`.`t1`.`a`) = `test`.`t2`.`c`)))))
select a from t1 group by a
having a in (select c from t2 where d >= some(select e from t3 where max(b)=e));
a
2
3
explain extended
select a from t1
where a in (select c from t2 where d >= some(select e from t3 where b=e));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ref it1a,iab iab 4 test.t2.c 1 100.00 Using where; Using index; End temporary
3 DEPENDENT SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where
Warnings:
Note 1276 Field or reference 'test.t1.b' of SELECT #3 was resolved in SELECT #1
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t1`.`a` = `test`.`t2`.`c`) and <nop>(<expr_cache><`test`.`t2`.`d`,`test`.`t1`.`b`>(<in_optimizer>(`test`.`t2`.`d`,<exists>(select `test`.`t3`.`e` from `test`.`t3` where ((`test`.`t1`.`b` = `test`.`t3`.`e`) and (<cache>(`test`.`t2`.`d`) >= `test`.`t3`.`e`)))))))
select a from t1
where a in (select c from t2 where d >= some(select e from t3 where b=e));
a
2
2
2
3
1
drop table t1, t2, t3;
create table t2 (a int, b int, key(a), key(b));
insert into t2 values (3,3),(3,3),(3,3);
select 1 from t2 where
t2.a > 1
or
t2.a = 3 and not t2.a not in (select t2.b from t2);
1
1
1
1
drop table t2;
create table t1 (a1 int key);
create table t2 (b1 int);
insert into t1 values (5);
explain select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
id select_type table type possible_keys key key_len ref rows Extra