SQL Server 多条记录的某个字段拼接

USE [FM_Dev]GO/****** 对象:  UserDefinedFunction [dbo].[GetClassNameByStudentCode]    脚本日期: 05/23/2014 17:20:43 ******/SET ANSI_NULLS ONGOSET QUOTED_IDENTIFIER ONGO-- =============================================-- Author: -- Create date: 2014年5月7日-- Description: 根据学员编号获取学员报读的班级名称拼接字符串-- =============================================CREATE FUNCTION [dbo].[GetClassNameByStudentCode] (    @StudentCode varchar(50))RETURNS varchar(100)ASBEGIN    declare @ClassName nvarchar(200)    set @ClassName=''    select @ClassName = @ClassName + ClassName + ','     from FM_Class cls    join FM_StudentClass sc on sc.ClassCode=cls.ClassCode     where sc.code=@StudentCode    order by cls.Id    if @ClassName<>''     begin        select @ClassName = left(@ClassName, len(@ClassName)-1)    end    return @ClassNameEND