SQLSERVER 删除重复记录

SQLSERVER 删除重复记录 


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)


(二)
比方说
在A表中存在一个字段“name”,
而且不同记录之间的“name”值有可能会相同,
现在就是需要查询出在该表中的各记录之间,“name”值存在重复的项;
Select
Name,Count(*) From A Group By Name Having Count(*) > 1


如果还查性别也相同大则如下:
Select Name,sex,Count(*) From A Group By Name,sex Having
Count(*) > 1

posted @ 2012-09-22 08:45  tiasys  阅读(12395)  评论(1编辑  收藏  举报