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)