<div class=”jb51code”>
<pre class=”brush:sql;”>
–创建测试表
CREATE TABLE [dbo].[testtab](
[id] nchar NULL,[name] nchar NULL
) ;
–向测试表插入测试数据
insert into testtab values(‘1′,’1’);
insert into testtab values(‘1′,’1’);
insert into testtab values(‘2′,’2’);
insert into testtab values(‘2′,’2’);
insert into testtab values(‘3′,’3’);
insert into testtab values(‘3′,’3’);

–创建临时表并向临时表中插入测试表testtab中数据以及添加自增id：autoID
select identity(int,1,1) as autoID,* into #Tmp from testtab
–根据autoID删除临时表#tmp中的重复数据，只保留每组重复数据中的第一条
delete #Tmp where autoID in(select max(autoID) from #Tmp group by id);
–清除testtab表中的所有数据
delete testtab;
–向testtab表中插入#Tmp表中被处理过的数据
insert into testtab select id,name from #Tmp;
–删除临时表#Tmp
drop table #Tmp;