第1个回答 2011-04-02
查询C字段有重复的记录吗?
如果是小表可以这样写:
select a from tabname
where c in
(select c from tabname group by c having count(1) >1 )
大表(需建c列索引):
select a from tabname a
where exists (select c from tabname b where b.c=a.c group by c having count(1) >1 )
第2个回答 推荐于2018-03-01
SELECT * FROM tab WHERE C in (
SELECT C
FROM tab
GROUP BY C
HAVING COUNT(A) > 1 )本回答被提问者和网友采纳
第3个回答 2011-04-01
select A from 表
group by A
having count(C)>=2
第4个回答 2011-04-01
select A FROM 表
where C in (
SELECT C FROM 表
group by C
having count(C)>1)