Oracle 删除重复数据只留一条

Posted SpeedHorse

tags:

篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了Oracle 删除重复数据只留一条相关的知识,希望对你有一定的参考价值。

 
转自http://www.cnblogs.com/252e/archive/2012/09/13/2682817.html
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(Id)来判断
 
select * from 表 where Id in (select Id from 表 group byId having count(Id) > 1)
 
2、删除表中多余的重复记录,重复记录是根据单个字段(Id)来判断,只留有rowid最小的记录
 
DELETE from 表 WHERE (id) IN ( SELECT id FROM 表 GROUP BY id HAVING COUNT(id) > 1) AND ROWID NOT IN (SELECT MIN(ROWID) FROM 表 GROUP BY id HAVING COUNT(*) > 1);
 
3、查找表中多余的重复记录(多个字段)
 
select * from 表 a where (a.Id,a.seq) in(select Id,seq from 表 group by Id,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 表 a where (a.Id,a.seq) in (select Id,seq from 表 group by Id,seq having count(*) > 1) and rowid not in (select min(rowid) from 表 group by Id,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 表 a where (a.Id,a.seq) in (select Id,seq from 表 group by Id,seq having count(*) > 1) and rowid not in (select min(rowid) from 表 group by Id,seq having count(*)>1)

以上是关于Oracle 删除重复数据只留一条的主要内容,如果未能解决你的问题,请参考以下文章

Oracle 删除重复数据只留一条

Oracle 删除重复数据只留一条

Oracle 删除重复数据只留一条

Oracle 删除重复数据只留一条

Oracle 删除重复数据只留一条

Oracle 删除重复数据只留一条