原文:
MSSQL sql server 2005/2008 row_number()函数应用之–删除表中重复记录,只保留一条不重复数据
转自:http://www.maomao365.com/?p=4942
下文主要讲述：重复数据只获取一条的方法
row_number函数在数据库中的功能是为每一行 按照一定的规则生成一个编号，
我们常常利用这一属性，对表进行分页操作，下文我们将讲述采用 row_number函数删除表中重复数据行
/*建表*/ create table A(keyId int,info varchar(20)) go /*生成数据*/ insert into A(keyId,info)values (1,'a'),(2,'b'),(3,'C'),(4,'d'),(5,'e'), (1,'a'),(21,'b1'),(31,'C1'),(4,'d'),(51,'e'), (1,'a'),(6,'b1'),(7,'C1'),(4,'d000'),(10,'e') go /*删除 keyId重复数据 中的另外几条*/ delete [A2] from (select row_number() over (Partition By keyId order by keyId) as keyId2,* from A ) as [A2] where [A2].keyId2 >1 /* /*删除 所有列都重复数据 中的另外几条*/ delete [A2] from (select row_number() over (Partition By keyId,info order by keyId) as keyId2,* from A ) as [A2] where [A2].keyId2 >1 */ /*展示删除后的数据*/ select * from A go truncate table A drop table A go
