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sql 删除重复行

时间:2014-07-27 22:38:29      阅读:233      评论:0      收藏:0      [点我收藏+]

标签:sql   text   rom   a   3   select   记录   class   

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)

sql 删除重复行,布布扣,bubuko.com

sql 删除重复行

标签:sql   text   rom   a   3   select   记录   class   

原文地址:http://www.cnblogs.com/gongyu/p/3871573.html

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