sqlserver中函数的用法简单示例

1.写函数
CREATE    function dbo.C_InfoGetCategory (
 @CategoryID int)
returns nvarchar(200)
as
begin
if @CategoryID=-1
return ''
declare @Name nvarchar(200)
select @Name=name from C_InfoCategory where CategoryID=@CategoryID
return @Name

end

2.调用函数
select  dbo.C_InfoGetCategory (Cate.CategoryID) as catename from aa