SQLServer 数据集合的交、并、差集运算

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
/ 求表并集
1
2
3
4
5/
select from t1 union all select from t2
go
/求表并集不过滤重复
1
2
3
3
4
5/
select from t1 except select from t2
go
/求t1对t2的差集
1
2/
select from t1 intersect select from t2
go
/求t1对t2的交集
3/