如何利用for XML AUTO合并同一行的數據

比如數據：
a    b    c    d
1    2    3    4
1    2    3    5
1    2    2    3
1    1    1    1
.....

合并后的數據為：
a    b      c        d
1    1,2    1,2,3    1,3,4,5
......

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写函数吧,2000

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2005

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SQL code:
CREATE FUNCTION GET_STRING(@NAME VARCHAR(10))
RETURNS VARCHAR(50)
AS
BEGIN
DECLARE @CLASS VARCHAR(50)
SELECT @CLASS=ISNULL(@CLASS+',','')+NAME from TB WHERE NAME=@NAME
RETURN @CLASS
END

---

SQL code:
----------------------------------------------------------------
-- Author :fredrickhu(我是小F，向高手学习)
-- Date :2009-12-15 10:00:26
-- Version:
-- Microsoft SQL Server 2005 - 9.00.4035.00 (Intel X86)
-- Nov 24 2008 13:01:59
-- Copyright (c) 1988-2005 Microsoft Corporation
-- Developer Edition on Windows NT 5.2 (Build 3790: Service Pack 1)
--
--------------------------------------------------------------