select ret from tb_pro group by ret having count(*)>1
select id,ret from tb_pro where ret in (select ret from tb_pro group by ret having count(*) > 1)
查询字段内容有重复的记录SQL语句
select custemail from psm_cust_fund group by custemail having count(*)>1
select * from 表格名 where 字段名 in (select 字段名 from 表格名 group by 字段名 having count(*)>1)
如要保留其它字段
Select * From 表格名 Where 字段名 In (select 字段名 from 表格名 group by 字段名 having count(*)>1)
注意和以下这句的区别
Select * From 表格名 Where 字段名 In (select 字段名 from 表格名 group by 字段名 having count(字段名)>1)
查询同一表内多字段同时重复记录的SQL语句
比如现在有一人员表 (表名:peosons)
若想将姓名、身份证号、住址这三个字段完全相同的记录查询出来
select p1.* from persons p1,persons p2 where p1.id<>p2.id and p1.cardid = p2.cardid and p1.pname = p2.pname and p1.address = p2.address

查找所有重复标题的记录:
SELECT *
FROM t_info a
WHERE ((SELECT COUNT(*)
         FROM t_info
         WHERE Title = a.Title) > 1)
ORDER BY Title DESC
一。查找重复记录
1。查找全部重复记录
Select * From 表 Where 重复字段 In (Select 重复字段 From 表 Group By 重复字段 Having Count(*)>1)
2。过滤重复记录(只显示一条)
Select * From HZT Where ID In (Select Max(ID) From HZT Group By Title)
注:此处显示ID最大一条记录
二。删除重复记录
1。删除全部重复记录(慎用)
Delete 表 Where 重复字段 In (Select 重复字段 From 表 Group By 重复字段 Having Count(*)>1)
2。保留一条(这个应该是大多数人所需要的 ^_^)
Delete HZT Where ID Not In (Select Max(ID) From HZT Group By Title)
注:此处保留ID最大一条记录
1、查找表中多余的重复记录,重复记录是根据单个字段(peopleId)来判断
select * from people
where peopleId in (select   peopleId from   people group by   peopleId having count(peopleId) > 1)
2、删除表中多余的重复记录,重复记录是根据单个字段(peopleId)来判断,只留有rowid最小的记录
delete from people
where peopleId in (select   peopleId from people group by   peopleId   having count(peopleId) > 1)
and rowid not in (select min(rowid) from   people group by peopleId having count(peopleId )>1)
3、查找表中多余的重复记录(多个字段)
select * from vitae a
where (a.peopleId,a.seq) in   (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)
4、删除表中多余的重复记录(多个字段),只留有rowid最小的记录
delete from vitae a
where (a.peopleId,a.seq) in   (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)
and rowid not in (select min(rowid) from vitae group by peopleId,seq having count(*)>1)
5、查找表中多余的重复记录(多个字段),不包含rowid最小的记录
select * from vitae a
where (a.peopleId,a.seq) in   (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)
and rowid not in (select min(rowid) from vitae group by peopleId,seq having count(*)>1)

补充:
有两个以上的重复记录,一是完全重复的记录,也即所有字段均重复的记录,二是部分关键字段重复的记录,比如Name字段重复,而其他字段不一定重复或都重复可以忽略。
1、对于第一种重复,比较容易解决,使用
select distinct * from tableName
就可以得到无重复记录的结果集。
如果该表需要删除重复的记录(重复记录保留1条),可以按以下方法删除
select distinct * into #Tmp from tableName
drop table tableName
select * into tableName from #Tmp
drop table #Tmp
发生这种重复的原因是表设计不周产生的,增加唯一索引列即可解决。
2、这类重复问题通常要求保留重复记录中的第一条记录,操作方法如下
假设有重复的字段为Name,Address,要求得到这两个字段唯一的结果集
select identity(int,1,1) as autoID, * into #Tmp from tableName
select min(autoID) as autoID into #Tmp2 from #Tmp group by Name,autoID
select * from #Tmp where autoID in(select autoID from #tmp2)
最后一个select即得到了Name,Address不重复的结果集(但多了一个autoID字段,实际写时可以写在select子句中省去此列)

http://hi.baidu.com/wuyuankun/item/7e5808cc42f1ab3399b4986c