復制代碼 代碼如下:

Create Table dbo.Employee (
[Id] int Primary KEY ,
[Name] varchar(50),
[Age] int,
[Sex] bit default 1
)
Insert Into Employee ([Id] , [Name] , [Age] , [Sex] ) Values(1,'James',25,default)
Insert Into Employee ([Id] , [Name] , [Age] , [Sex] ) Values(2,'James',25,default)
Insert Into Employee ([Id] , [Name] , [Age] , [Sex] ) Values(3,'James',25,default)
Insert Into Employee ([Id] , [Name] , [Age] , [Sex] ) Values(4,'Lisa',24,0)
Insert Into Employee ([Id] , [Name] , [Age] , [Sex] ) Values(5,'Lisa',24,0)
Insert Into Employee ([Id] , [Name] , [Age] , [Sex] ) Values(6,'Lisa',24,0)
Insert Into Employee ([Id] , [Name] , [Age] , [Sex] ) Values(7,'Mirsa',23,0)
Insert Into Employee ([Id] , [Name] , [Age] , [Sex] ) Values(8,'Mirsa',23,0)
Insert Into Employee ([Id] , [Name] , [Age] , [Sex] ) Values(9,'Mirsa',23,0)
Insert Into Employee ([Id] , [Name] , [Age] , [Sex] ) Values(10,'John',26,default)
Insert Into Employee ([Id] , [Name] , [Age] , [Sex] ) Values(11,'Abraham',28,default)
Insert Into Employee ([Id] , [Name] , [Age] , [Sex] ) Values(12,'Lincoln',30,default)

還可以使用CTE (Common Table Expressions):

復制代碼 代碼如下:

With Dups as
(
select ROW_NUMBER() Over(Partition by [Name] Order by (SELECT 0)) as rn
FROM Employee
)
Delete From Dups
Where rn>1;

復制代碼 代碼如下:

WITH Dups As
(
Select [ID],[Name],[Age],[Sex]
, ROW_NUMBER() OVER(Partition By [Name] Order By (SELECT 0)) AS rn
,RANK() OVER(Partition By [Name] Order By (SELECT 0)) AS rnk
FROM Employee
)
DELETE FROM Dups
WHERE rn<>rnk;

下面是這四個T-SQL查詢的執行計劃:

希望這篇POST對您開發有幫助.作者：Petter Liu