求sql语句

[Methodor]

列出所有有重复数据的,举例:
表:tb1
列:col1,col2,col3
列出所有col2数据有重复的行

sql如何写?

[tianyusunkuangyu]

select * from tb1 where col2 in(select col2 from tb1 group col2 having count(col2)>1)

[zhouhan0048]

select * from emp where
(select count(*) from emp e
where e.name=emp.name) >1

[arrow_gx]

select * from tb1 where col2 in(select col2 from tb1 group by col2 having count(col2)>1)

[zhouhan0048]

select * from emp where name in
(select name from emp group by name having count(*)>1)

也可以

[hyf_0023]

select col2,count(*) from tb1 group by col2 having count(*)>1;