ndb_subquery.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

drop table if exists t1;
drop table if exists t2;
create table t1 (p int not null primary key, u int not null, o int not null,
unique (u), key(o)) engine=ndb;
create table t2 (p int not null primary key, u int not null, o int not null,
unique (u), key(o)) engine=ndb;
insert into t1 values (1,1,1),(2,2,2),(3,3,3);
insert into t2 values (1,1,1),(2,2,2),(3,3,3), (4,4,4), (5,5,5);
explain select * from t2 where p NOT IN (select p from t1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	5	Using where
2	DEPENDENT SUBQUERY	t1	unique_subquery	PRIMARY	PRIMARY	4	func	1	Using index
select * from t2 where p NOT IN (select p from t1) order by p;
p	u	o
4	4	4
5	5	5
explain select * from t2 where p NOT IN (select u from t1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	5	Using where
2	DEPENDENT SUBQUERY	t1	unique_subquery	u	u	4	func	1	Using index
select * from t2 where p NOT IN (select u from t1) order by p;
p	u	o
4	4	4
5	5	5
explain select * from t2 where p NOT IN (select o from t1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	5	Using where
2	DEPENDENT SUBQUERY	t1	index_subquery	o	o	4	func	1	Using index
select * from t2 where p NOT IN (select o from t1) order by p;
p	u	o
4	4	4
5	5	5
explain select * from t2 where p NOT IN (select p+0 from t1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	5	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	3	Using where
select * from t2 where p NOT IN (select p+0 from t1) order by p;
p	u	o
4	4	4
5	5	5
drop table t1;
drop table t2;
create table t1 (p int not null primary key, u int not null) engine=ndb;
insert into t1 values (1,1),(2,2),(3,3);
create table t2 as 
select t1.*
from t1 as t1, t1 as t2, t1 as t3, t1 as t4, t1 as t5, t1 as t6, t1 as t7, t1 as t8
where t1.u = t2.u
and t2.u = t3.u
and t3.u = t4.u
and t4.u = t5.u
and t5.u = t6.u
and t6.u = t7.u
and t7.u = t8.u;
select * from t2 order by 1;
p	u
1	1
2	2
3	3
drop table t1;
drop table t2;