sql 删除表中的重复记录_Sql Server

sql 删除表中的重复记录

2020-05-15 15:10鱼草野 Sql Server

本文主要介绍了sql 删除表中的重复记录的方法，具有一定的参考价值，下面跟着小编一起来看下吧

遇见了表中存在重复的记录的问题，直接写sql删除时最快的，才不要慢慢的复制到excel表中慢慢的人工找呢

如下sql，找出重复的记录，和重复记录中ID值最小的记录（表中ID为自增长）

				?

									select MIN(ID) as id, StructSN ,Date,UserID,StarCount,COUNT(StructSN) as c

									from T_Dor_StructStar 

									where Date >= '20160919'

									group by StructSN ,Date,UserID,StarCount

									having COUNT(StructSN) > 1

然后就可以直接删除，基本原理就是，找到重复记录的每一条记录，排除掉重复id最小的记录，删除剩余的重复记录。

				?

									delete from T_Dor_StructStar

									where ID in (

									select s.ID from T_Dor_StructStar s,

									(

									select MIN(ID) as id, StructSN ,Date,UserID,StarCount,COUNT(StructSN) as c

									from T_Dor_StructStar 

									where Date >= '20160919'

									group by StructSN ,Date,UserID,StarCount

									having COUNT(StructSN) > 1

									)a

									where

									a.Date = s.Date

									and a.StructSN = s.StructSN

									and a.UserID = s.UserID

									and a.StarCount = s.StarCount

									and a.id != s.ID

									)