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id name
3 a3
4 a4
5 a5
6 a3
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id name
3 a3
4 a4
5 a5
SQLÓï¾ä£ºselect * from users a group by ID,Name having ID=(select min(ID)from users where Name=a.Name)
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SQL code:
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-- =============================================
-- Author: T.O.P
-- Create date: 20091127
-- Version: SQL SERVER 2000
-- =============================================
declare @TB table([id] int,[name] varchar(2))
insert @TB
select 3,'a3' union all
select 4,'a4' union all
select 5,'a5' union all
select 6,'a3'
select *
from @TB a
where not exists(select 1 from @tb where a.id>id and a.name = name)
--²âÊÔ½á¹û:
/*
id name
----------- ----
3 a3
4 a4
5 a5
£¨ËùÓ°ÏìµÄÐÐÊýΪ 3 ÐУ©
*/
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