sql 删除重复行怎么写

sql 删除重复行怎么写

 

问题补充：

就是删除数据库中完全一样的，仅仅保留一条。

最佳答案

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)

参考资料： 网上有