MSSQL sql server 2005/2008 row_number()函数应用之–删除表中重

转自:http://www.maomao365.com/?p=4942

**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**

create table A(keyId int,info varchar(200))
go 

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,'猫猫小屋'),
(1,'a'),(6,'b1'),(7,'C1'),(4,'d000'),(10,'maomao365.com')
go


delete [A2] from 
(select row_number() over (Partition By keyId order by keyId) as keyId2,* from A ) as [A2]
where [A2].keyId2  >1 


delete [A2] from 
(select row_number() over (Partition By keyId,info order by keyId) as keyId2,* from A ) as [A2]
where [A2].keyId2  >1 
 */



select * from A 
go

truncate table A 
drop table A 
go