分享SQL重复记录查询的几种方法

分享SQL重复记录查询的几种方法_第1张图片

 

SQL重复记录查询的几种方法,需要的朋友可以参考一下

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

代码如下:


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

代码如下:


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)

代码如下:


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

代码如下:


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

代码如下:


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)

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