select RESOURCE.TYPE, A.FILENAME, A.PATH, a.hashvalue, A.EFFECTIVEDATE from version A Left Join RESOURCE on RESOURCE.ID = A.RESOURCEID AND not exists(select * from version B where A.RESOURCEID = B.ResourceID and A.PROVIDERID = B.PROVIDERID and A.MCID = B.MCID )
没看懂。A 跟B 其实是一个表吧?那怎么可能出现 A.RESOURCEID = B.ResourceID 呢?若不存在写的意义何在?
--这逻辑看起来确实....!!! ???
SELECT RESOURCE.TYPE ,
A.FILENAME ,
A.PATH ,
a.hashvalue ,
A.EFFECTIVEDATE
FROM version A
LEFT JOIN RESOURCE ON RESOURCE.ID = A.RESOURCEID
AND NOT EXISTS ( SELECT *
FROM version B
WHERE A.RESOURCEID = B.ResourceID
AND A.PROVIDERID = B.PROVIDERID
AND A.MCID = B.MCID )