create table tb(id int,val varchar(10)) insert into tb select 1,'a' union all select 2,'b' union all select 3,'c' go select a.id,b.val from tb a,tb b order by a.id /* id val ----------- ---------- 1 a 1 b 1 c 2 a 2 b 2 c 3 a 3 b 3 c(9 行受影响) */ go drop table tb
create table tb(id int) insert into tb select 1 union all select 2 union all select 3 create table tb1(val varchar(10)) insert into tb1 select 'a' union all select 'b' union all select 'c' go select * from tb,tb1 order by id /* id val ----------- ---------- 1 a 1 b 1 c 2 a 2 b 2 c 3 a 3 b 3 c(9 行受影响)*/ go drop table tb,tb1
3 b
1 c
为啥,最下面的是1
insert into tb select 1,'a' union all select 2,'b' union all select 3,'c'
go
select a.id,b.val from tb a,tb b order by a.id
/*
id val
----------- ----------
1 a
1 b
1 c
2 a
2 b
2 c
3 a
3 b
3 c(9 行受影响)
*/
go
drop table tb
insert into tb select 1 union all select 2 union all select 3
create table tb1(val varchar(10))
insert into tb1 select 'a' union all select 'b' union all select 'c'
go
select * from tb,tb1 order by id
/*
id val
----------- ----------
1 a
1 b
1 c
2 a
2 b
2 c
3 a
3 b
3 c(9 行受影响)*/
go
drop table tb,tb1