分拆列值

有表tb, 如下:
id          value
----------- -----------
1           aa,bb
2           aaa,bbb,ccc
欲按id,分拆value列, 分拆后结果如下:
id          value
----------- --------
1           aa
1           bb
2           aaa
2           bbb
2           ccc

创建表和测试数据

create table tb(id int,value varchar(30))
 insert into tb values(1,'aa,bb')
 insert into tb values(2,'aaa,bbb,ccc')
 go

　　1. 旧的解决方法(sql server 2000)

SELECT TOP 8000 id = IDENTITY(int, 1, 1) INTO # FROM syscolumns a, syscolumns b 
 
SELECT A.id, SUBSTRING(A.[values], B.id, CHARINDEX(',', A.[values] + ',', B.id) - B.id)
 FROM tb A, # B
 WHERE SUBSTRING(',' + A.[values], B.id, 1) = ','
 
DROP TABLE #
 

　　2. 新的解决方法(sql server 2005)

SELECT A.id, B.value
 FROM(
     SELECT id, [value] = CONVERT(xml,'<root><v>' + REPLACE([value], ',', '</v><v>') + '</v></root>') FROM tb
 )A
 OUTER APPLY(
     SELECT value = N.v.value('.', 'varchar(100)') FROM A.[value].nodes('/root/v') N(v)
 )B
 
DROP TABLE tb
 

　　/*
id          value
----------- ------------------------------
1           aa
1           bb
2           aaa
2           bbb
2           ccc