SQL重复记录查询的几种方法

参考文章:
http://database.51cto.com/art/201011/235159.htm

1,查找表中多余的重复记录,重复记录是根据单个字段来判断

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,查找表中对于的重复记录(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),只保留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)
    原文作者:海贼之路飞
    原文地址: https://www.jianshu.com/p/1035a974435f
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