SQL Server自定义函数(Tablevalued Functions)

自定义函数(User-Defined Function)有两种，一种是标量UDF(Scalar-valued Functions)和表值UDF(Table-valued Functions)，前者只返回单个数据值，而后者则返回一个表。前面演示了标量自定义函数，http://www.cnblogs.com/insus/articles/1918983.html  ，现在下面两个实例均演示表值自定义函数，

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE FUNCTION [dbo].[udf_SuperUser]
(
)
RETURNS @SuperUser TABLE([Account] nvarchar(30),[Password] nvarchar(30))
AS
BEGIN
    INSERT SuperUser ([Account],[Password]) VALUES('Admin','mypassword@2010');
    RETURN
END

  

另一个例子,

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE FUNCTION [dbo].[udf_Supervisor]
(
)
RETURNS TABLE 
AS
RETURN 
(
    SELECT [SupervisorId],e.[WorkNumber],[EmployeeName],w.[WorkGroupId],[WorkGroupName],s.[IsActive] 
    FROM [Supervisor] s 
    LEFT JOIN [Employee] e ON (s.[WorkNumber]=e.[WorkNumber])
    LEFT JOIN [WorkGroup] w ON (s.[WorkGroupId] = w.[WorkGroupId])
)