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分享-针对重复记录的几个实用的SQL语法

发布时间: 2012-01-15 22:57:48 作者: rapoo

分享--针对重复记录的几个实用的SQL语法
在对数据进行分析处理时,有时候会遇到要处理重复记录的问题,下面分享下针对重复记录的几个SQL语法。
http://www.powerbibbs.com/thread-184-1-1.html

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)




[解决办法]
这个以前大版整理过了

http://topic.csdn.net/u/20080626/00/43d0d10c-28f1-418d-a05b-663880da278a.html?82976
[解决办法]
不错。。
[解决办法]

探讨
在对数据进行分析处理时,有时候会遇到要处理重复记录的问题,下面分享下针对重复记录的几个SQL语法。
http://www.powerbibbs.com/thread-184-1-1.html

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 f……

[解决办法]
探讨
在对数据进行分析处理时,有时候会遇到要处理重复记录的问题,下面分享下针对重复记录的几个SQL语法。
http://www.powerbibbs.com/thread-184-1-1.html

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 f……

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