subselect.result

这是linux下运行的mysql软件包,可用于linux 下安装 php + mysql + apach 的网络配置

create table t2 (a int);
create table t3 (b int);
insert into t2 values (1);
insert into t3 values (1),(2);
INSERT INTO t1 (x) VALUES ((SELECT x FROM t1));
ERROR HY000: You can't specify target table 't1' for update in FROM clause
INSERT INTO t1 (x) VALUES ((SELECT b FROM t3));
ERROR 21000: Subquery returns more than 1 row
INSERT INTO t1 (x) VALUES ((SELECT a FROM t2));
select * from t1;
x
1
insert into t2 values (1);
INSERT DELAYED INTO t1 (x) VALUES ((SELECT SUM(a) FROM t2));
select * from t1;
x
1
2
INSERT INTO t1 (x) select (SELECT SUM(a)+1 FROM t2) FROM t2;
select * from t1;
x
1
2
3
3
INSERT INTO t1 (x) select (SELECT SUM(x)+2 FROM t1) FROM t2;
select * from t1;
x
1
2
3
3
11
11
INSERT DELAYED INTO t1 (x) VALUES ((SELECT SUM(x) FROM t2));
ERROR 42S22: Unknown column 'x' in 'field list'
INSERT DELAYED INTO t1 (x) VALUES ((SELECT SUM(a) FROM t2));
select * from t1;
x
1
2
3
3
11
11
2
drop table t1, t2, t3;
CREATE TABLE t1 (x int not null, y int, primary key (x));
create table t2 (a int);
create table t3 (a int);
insert into t2 values (1);
insert into t3 values (1),(2);
select * from t1;
x	y
replace into t1 (x, y) VALUES ((SELECT x FROM t1), (SELECT a+1 FROM t2));
ERROR HY000: You can't specify target table 't1' for update in FROM clause
replace into t1 (x, y) VALUES ((SELECT a FROM t3), (SELECT a+1 FROM t2));
ERROR 21000: Subquery returns more than 1 row
replace into t1 (x, y) VALUES ((SELECT a FROM t2), (SELECT a+1 FROM t2));
select * from t1;
x	y
1	2
replace into t1 (x, y) VALUES ((SELECT a FROM t2), (SELECT a+2 FROM t2));
select * from t1;
x	y
1	3
replace DELAYED into t1 (x, y) VALUES ((SELECT a+3 FROM t2), (SELECT a FROM t2));
select * from t1;
x	y
1	3
4	1
replace DELAYED into t1 (x, y) VALUES ((SELECT a+3 FROM t2), (SELECT a+1 FROM t2));
select * from t1;
x	y
1	3
4	2
replace LOW_PRIORITY into t1 (x, y) VALUES ((SELECT a+1 FROM t2), (SELECT a FROM t2));
select * from t1;
x	y
1	3
4	2
2	1
drop table t1, t2, t3;
SELECT * FROM (SELECT 1) b WHERE 1 IN (SELECT *);
ERROR HY000: No tables used
CREATE TABLE t2 (id int(11) default NULL, KEY id (id)) ENGINE=MyISAM CHARSET=latin1;
INSERT INTO t2 VALUES (1),(2);
SELECT * FROM t2 WHERE id IN (SELECT 1);
id
1
EXPLAIN EXTENDED SELECT * FROM t2 WHERE id IN (SELECT 1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t2	ref	id	id	5	const	1	Using where; Using index
Warnings:
Note	1249	Select 2 was reduced during optimization
Note	1003	select `test`.`t2`.`id` AS `id` from `test`.`t2` where (`test`.`t2`.`id` = 1)
SELECT * FROM t2 WHERE id IN (SELECT 1 UNION SELECT 3);
id
1
SELECT * FROM t2 WHERE id IN (SELECT 1+(select 1));
id
2
EXPLAIN EXTENDED SELECT * FROM t2 WHERE id IN (SELECT 1+(select 1));
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t2	ref	id	id	5	const	1	Using where; Using index
Warnings:
Note	1249	Select 3 was reduced during optimization
Note	1249	Select 2 was reduced during optimization
Note	1003	select `test`.`t2`.`id` AS `id` from `test`.`t2` where (`test`.`t2`.`id` = (1 + 1))
EXPLAIN EXTENDED SELECT * FROM t2 WHERE id IN (SELECT 1 UNION SELECT 3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t2	index	NULL	id	5	NULL	2	Using where; Using index
2	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
3	DEPENDENT UNION	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
NULL	UNION RESULT	<union2,3>	ALL	NULL	NULL	NULL	NULL	NULL	
Warnings:
Note	1003	select `test`.`t2`.`id` AS `id` from `test`.`t2` where <in_optimizer>(`test`.`t2`.`id`,<exists>(select 1 AS `Not_used` having (<cache>(`test`.`t2`.`id`) = <null_helper>(1)) union select 1 AS `Not_used` having (<cache>(`test`.`t2`.`id`) = <null_helper>(3))))
SELECT * FROM t2 WHERE id IN (SELECT 5 UNION SELECT 3);
id
SELECT * FROM t2 WHERE id IN (SELECT 5 UNION SELECT 2);
id
2
INSERT INTO t2 VALUES ((SELECT * FROM t2));
ERROR HY000: You can't specify target table 't2' for update in FROM clause
INSERT INTO t2 VALUES ((SELECT id FROM t2));
ERROR HY000: You can't specify target table 't2' for update in FROM clause
SELECT * FROM t2;
id
1
2
CREATE TABLE t1 (id int(11) default NULL, KEY id (id)) ENGINE=MyISAM CHARSET=latin1;
INSERT INTO t1 values (1),(1);
UPDATE t2 SET id=(SELECT * FROM t1);
ERROR 21000: Subquery returns more than 1 row
drop table t2, t1;
create table t1 (a int);
insert into t1 values (1),(2),(3);
select 1 IN (SELECT * from t1);
1 IN (SELECT * from t1)
1
select 10 IN (SELECT * from t1);
10 IN (SELECT * from t1)
0
select NULL IN (SELECT * from t1);
NULL IN (SELECT * from t1)
NULL
update t1 set a=NULL where a=2;
select 1 IN (SELECT * from t1);
1 IN (SELECT * from t1)
1
select 3 IN (SELECT * from t1);
3 IN (SELECT * from t1)
1
select 10 IN (SELECT * from t1);
10 IN (SELECT * from t1)
NULL
select 1 > ALL (SELECT * from t1);
1 > ALL (SELECT * from t1)
0
select 10 > ALL (SELECT * from t1);
10 > ALL (SELECT * from t1)
NULL
select 1 > ANY (SELECT * from t1);
1 > ANY (SELECT * from t1)
NULL
select 10 > ANY (SELECT * from t1);
10 > ANY (SELECT * from t1)
1
drop table t1;
create table t1 (a varchar(20));
insert into t1 values ('A'),('BC'),('DEF');
select 'A' IN (SELECT * from t1);
'A' IN (SELECT * from t1)
1
select 'XYZS' IN (SELECT * from t1);
'XYZS' IN (SELECT * from t1)
0
select NULL IN (SELECT * from t1);
NULL IN (SELECT * from t1)
NULL
update t1 set a=NULL where a='BC';
select 'A' IN (SELECT * from t1);
'A' IN (SELECT * from t1)
1
select 'DEF' IN (SELECT * from t1);
'DEF' IN (SELECT * from t1)
1
select 'XYZS' IN (SELECT * from t1);
'XYZS' IN (SELECT * from t1)
NULL
select 'A' > ALL (SELECT * from t1);
'A' > ALL (SELECT * from t1)
0
select 'XYZS' > ALL (SELECT * from t1);
'XYZS' > ALL (SELECT * from t1)
NULL
select 'A' > ANY (SELECT * from t1);
'A' > ANY (SELECT * from t1)
NULL
select 'XYZS' > ANY (SELECT * from t1);
'XYZS' > ANY (SELECT * from t1)
1
drop table t1;
create table t1 (a float);
insert into t1 values (1.5),(2.5),(3.5);
select 1.5 IN (SELECT * from t1);
1.5 IN (SELECT * from t1)
1
select 10.5 IN (SELECT * from t1);
10.5 IN (SELECT * from t1)
0
select NULL IN (SELECT * from t1);
NULL IN (SELECT * from t1)
NULL
update t1 set a=NULL where a=2.5;
select 1.5 IN (SELECT * from t1);
1.5 IN (SELECT * from t1)
1
select 3.5 IN (SELECT * from t1);
3.5 IN (SELECT * from t1)
1
select 10.5 IN (SELECT * from t1);
10.5 IN (SELECT * from t1)
NULL
select 1.5 > ALL (SELECT * from t1);
1.5 > ALL (SELECT * from t1)
0
select 10.5 > ALL (SELECT * from t1);
10.5 > ALL (SELECT * from t1)
NULL
select 1.5 > ANY (SELECT * from t1);
1.5 > ANY (SELECT * from t1)
NULL
select 10.5 > ANY (SELECT * from t1);
10.5 > ANY (SELECT * from t1)
1
explain extended select (select a+1) from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	
Warnings:
Note	1276	Field or reference 'a' of SELECT #2 was resolved in SELECT #1
Note	1249	Select 2 was reduced during optimization
Note	1003	select (`test`.`t1`.`a` + 1) AS `(select a+1)` from `test`.`t1`
select (select a+1) from t1;
(select a+1)
2.5
NULL
4.5
drop table t1;
CREATE TABLE t1 (a int(11) NOT NULL default '0', PRIMARY KEY  (a));
CREATE TABLE t2 (a int(11) default '0', INDEX (a));
INSERT INTO t1 VALUES (1),(2),(3),(4);
INSERT INTO t2 VALUES (1),(2),(3);
SELECT t1.a, t1.a in (select t2.a from t2) FROM t1;
a	t1.a in (select t2.a from t2)
1	1
2	1
3	1
4	0
explain extended SELECT t1.a, t1.a in (select t2.a from t2) FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	index	NULL	PRIMARY	4	NULL	4	Using index
2	DEPENDENT SUBQUERY	t2	index_subquery	a	a	5	func	2	Using index
Warnings:
Note	1003	select `test`.`t1`.`a` AS `a`,<in_optimizer>(`test`.`t1`.`a`,<exists>(<index_lookup>(<cache>(`test`.`t1`.`a`) in t2 on a checking NULL))) AS `t1.a in (select t2.a from t2)` from `test`.`t1`
CREATE TABLE t3 (a int(11) default '0');
INSERT INTO t3 VALUES (1),(2),(3);
SELECT t1.a, t1.a in (select t2.a from t2,t3 where t3.a=t2.a) FROM t1;
a	t1.a in (select t2.a from t2,t3 where t3.a=t2.a)
1	1
2	1
3	1
4	0
explain extended SELECT t1.a, t1.a in (select t2.a from t2,t3 where t3.a=t2.a) FROM t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	index	NULL	PRIMARY	4	NULL	4	Using index
2	DEPENDENT SUBQUERY	t2	ref_or_null	a	a	5	func	2	Using where; Using index
2	DEPENDENT SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	3	Using where
Warnings:
Note	1003	select `test`.`t1`.`a` AS `a`,<in_optimizer>(`test`.`t1`.`a`,<exists>(select 1 AS `Not_used` from `test`.`t2` join `test`.`t3` where ((`test`.`t3`.`a` = `test`.`t2`.`a`) and ((<cache>(`test`.`t1`.`a`) = `test`.`t2`.`a`) or isnull(`test`.`t2`.`a`))) having <is_not_null_test>(`test`.`t2`.`a`))) AS `t1.a in (select t2.a from t2,t3 where t3.a=t2.a)` from `test`.`t1`
drop table t1,t2,t3;
create table t1 (a float);
select 10.5 IN (SELECT * from t1 LIMIT 1);
ERROR 42000: This version of MySQL doesn't yet support 'LIMIT & IN/ALL/ANY/SOME subquery'
select 10.5 IN (SELECT * from t1 LIMIT 1 UNION SELECT 1.5);
ERROR 42000: This version of MySQL doesn't yet support 'LIMIT & IN/ALL/ANY/SOME subquery'
drop table t1;
create table t1 (a int, b int, c varchar(10));
create table t2 (a int);
insert into t1 values (1,2,'a'),(2,3,'b'),(3,4,'c');
insert into t2 values (1),(2),(NULL);
select a, (select a,b,c from t1 where t1.a=t2.a) = ROW(a,2,'a'),(select c from t1 where a=t2.a)  from t2;
a	(select a,b,c from t1 where t1.a=t2.a) = ROW(a,2,'a')	(select c from t1 where a=t2.a)
1	1	a
2	0	b
NULL	0	NULL
select a, (select a,b,c from t1 where t1.a=t2.a) = ROW(a,3,'b'),(select c from t1 where a=t2.a) from t2;
a	(select a,b,c from t1 where t1.a=t2.a) = ROW(a,3,'b')	(select c from t1 where a=t2.a)
1	0	a
2	1	b
NULL	NULL	NULL
select a, (select a,b,c from t1 where t1.a=t2.a) = ROW(a,4,'c'),(select c from t1 where a=t2.a) from t2;
a	(select a,b,c from t1 where t1.a=t2.a) = ROW(a,4,'c')	(select c from t1 where a=t2.a)
1	0	a
2	0	b
NULL	0	NULL
drop table t1,t2;
create table t1 (a int, b real, c varchar(10));
insert into t1 values (1, 1, 'a'), (2,2,'b'), (NULL, 2, 'b');
select ROW(1, 1, 'a') IN (select a,b,c from t1);
ROW(1, 1, 'a') IN (select a,b,c from t1)
1
select ROW(1, 2, 'a') IN (select a,b,c from t1);
ROW(1, 2, 'a') IN (select a,b,c from t1)
0