请教关于这个SQL语句的问题
连接中 http://bbs.csdn.net/topics/391112939
with table1 as
(
SELECT 1 id,'00000002,00000003,00000004' code
)
, table2 as
(
SELECT '00000002' AS CODE ,'AAA'AS NAME UNION ALL
SELECT '00000003' AS CODE ,'BBB'AS NAME UNION ALL
SELECT '00000004' AS CODE ,'CCC'AS NAME UNION ALL
SELECT '00000005' AS CODE ,'DDD'AS NAME UNION ALL
SELECT '00000006' AS CODE ,'EEE'AS NAME
)
SELECT id, MAX(code) code, STUFF((SELECT ','+name FROM (select b.id, b.code, a.NAME from table2 a inner join table1 b on ','+b.CODE+',' like '%,'+a.code+',%') t WHERE id=t1.id FOR XML PATH('')), 1, 1, '') name
FROM (select b.id, b.code, a.NAME from table2 a inner join table1 b on ','+b.CODE+',' like '%,'+a.code+',%') t1
GROUP BY id
请问1.为什么用','+b.CODE+',' like '%,'+a.code+',%',其中的','+XX+','起什么作用,为什么两边加了逗号能分解出所有的CODE
2.FOR XML PATH使用有好的资料吗