sql之函数（Function）

一、带参返回字符串

 create function seek1(@id int)

  returns varchar(50)

  as

  begin

  declare @classname varchar(50)

  select @classname=className from class where classid=@id

  return @classname

  end

  go

查询

  select dbo.seek1(1) as name

二、不带参返回数据集

  create function seekDatas()

  returns table

  as

  return (select * from class)

  go

查询

  select * from dbo.seekDatas()

三、带参返回数据集

  create function seekDatasParamer(@id int)

  returns table

  as

  return (select * from class where classid=@id)

  go

  select * from dbo.seekDatasParamer(1)