他們的對應關系可以參考下面圖示相關測試實例如下： 
相關測試實例如下：
復制代碼 代碼如下:
use tempdb
go
if (object_id ('t1' ) is not null ) drop table t1
if (object_id ('t2' ) is not null ) drop table t2
go
create table t1 (a int )
insert into t1 select 1 union select 2 union select 3
create table t2 (a int )
insert into t2 select 3 union select 4 union select 5
go
select * from t1 union select * from t2
go
/* 求表並集
1
2
3
4
5*/
select * from t1 union all select * from t2
go
/*求表並集不過濾重復
1
2
3
3
4
5*/
select * from t1 except select * from t2
go
/*求t1對t2的差集
1
2*/
select * from t1 intersect select * from t2
go
/*求t1對t2的交集
3*/
