sql查询和删除重复字段的内容

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1、例如：id          name        value1              a                pp2              a                pp3              b                iii4              b                pp5              b                pp6              c                pp7              c                pp8

2、              c                iiiid是主键要求得到这样的结果id          name        value1              a                pp3              b                iii4              b                pp6              c                pp8              c                iii方法1delete  YourTable  w

3、here  [id]  not  in  (select  max([id])  from  YourTable  group  by  (name  +  value))方法2delete  afrom  表  a  left  join(select  id=min(id)  from  表  group  by  name,value)b  on  a.id=b.idwhere  b.id  is  null查询及删除重复记录的SQL语句查询及删除重复记录的SQL语句1、查找表中多余的重复记录，重复记录是根据单个字段（peopleI

4、d）来判断select*frompeoplewherepeopleIdin(select  peopleIdfrom  peoplegroupby  peopleIdhavingcount(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deletefrompeoplewherepeopleIdin(select  peopleIdfrompeoplegroupby  peopleId  havingcount(peopleId)>1)androwidnoti

5、n(selectmin(rowid)from  peoplegroupbypeopleIdhavingcount(peopleId)>1)3、查找表中多余的重复记录（多个字段）select*fromvitaeawhere(a.peopleId,a.seq)in  (selectpeopleId,seqfromvitaegroupbypeopleId,seqhavingcount(*)>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deletefromvitaeawhere(a.peopleId,a.seq)in  

6、(selectpeopleId,seqfromvitaegroupbypeopleId,seqhavingcount(*)>1)androwidnotin(selectmin(rowid)fromvitaegroupbypeopleId,seqhavingcount(*)>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*fromvitaeawhere(a.peopleId,a.seq)in  (selectpeopleId,seqfromvitaegroupbypeopleId,seqhavingcou

7、nt(*)>1)androwidnotin(selectmin(rowid)fromvitaegroupbypeopleId,seqhavingcount(*)>1)(二)比方说在A表中存在一个字段“name”，而且不同记录之间的“name”值有可能会相同，现在就是需要查询出在该表中的各记录之间，“name”值存在重复的项；SelectName,Count(*)FromAGroupByNameHavingCount(*)>1如果还查性别也相同大则如下:SelectName,sex,Count(*)FromAGroupByName,sexH

8、avingCount(*)>1(三)方法一declare@maxinteger,@idintegerdeclarecur_rowscursorlocalforselect主字段,count(*