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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
/* Çó±íºÏ¼¯
1
2
3
4
5*/
select * from t1 union all select * from t2
go
/*Çó±íºÏ¼¯²»¹ýÂËÖØ¸´
1
2
3
3
4
5*/
select * from t1 except select * from t2
go
/*Çót1¶Ôt2µÄ²î¼¯
1
2*/
select * from t1 intersect select * from t2
go
/*Çót1¶Ôt2µÄ½»¼¯
3*/
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