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SQL Server數(shù)據(jù)庫(kù)刪除數(shù)據(jù)集中重復(fù)數(shù)據(jù)實(shí)例講解

 更新時(shí)間：2015年08月18日 14:44:08   投稿：lijiao  
本文通過(guò)一個(gè)例子介紹了SQL Server數(shù)據(jù)庫(kù)中刪除數(shù)據(jù)集中的重復(fù)數(shù)據(jù)的操作過(guò)程,需要的朋友可以參考下

SQL Server數(shù)據(jù)庫(kù)操作中，有時(shí)對(duì)于表中的結(jié)果集，滿足一定規(guī)則我們則認(rèn)為是重復(fù)數(shù)據(jù)，而這些重復(fù)數(shù)據(jù)需要?jiǎng)h除。如何刪除呢？本文我們通過(guò)一個(gè)例子來(lái)加以說(shuō)明。

例子如下：

如下只要companyName,invoiceNumber,customerNumber三者都相同，我們則認(rèn)為是重復(fù)數(shù)據(jù)，下面的例子演示了如何刪除。

declare @InvoiceListMaster table ( ID int identity primary key ,  
 
companyName Nchar(20),  
 
invoiceNumber int,  
 
CustomerNumber int,  
 
rmaNumber int )  
 
insert  @InvoiceListMaster  
 
select N'華為', 1001,100,200  
 
union all  
 
select N'華為', 1001,100,300  
 
union all  
 
select N'華為', 1001,100,301  
 
union all  
 
select N'中興', 1002, 200,1     
 
union all  
 
select N'中興', 1002, 200,2  
 
select * from @InvoiceListMaster  
 
DELETE A  
 
from (  
 
select rown = ROW_NUMBER( )over( partition by companyname,  
 
invoicenumber,  
 
customerNumber   
 
order by companyname,  
 
invoicenumber,  
 
customerNumber ),  
 
companyname,  
 
invoicenumber,  
 
customerNumber  
 
from @InvoiceListMaster )a  
 
where exists ( select 1   
 
from ( select rown = ROW_NUMBER( )over( partition by companyname,  
 
invoicenumber,  
 
customerNumber   
 
order by companyname,  
 
invoicenumber,  
 
customerNumber ),  
 
companyname,  
 
invoicenumber,  
 
customerNumber  
 
from @InvoiceListMaster ) b  
 
where b.companyName = a.companyName  
 
and b.invoiceNumber = a.invoiceNumber  
 
and b.CustomerNumber = a.CustomerNumber  
 
and a.rown > b.rown  
 
)  
 
select * from @InvoiceListMaster

以上的例子就演示了SQL Server數(shù)據(jù)庫(kù)刪除數(shù)據(jù)集中重復(fù)數(shù)據(jù)的過(guò)程，希望本次的介紹能夠?qū)δ兴斋@！

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