为何COALESCE不起作用?
ttyp 2004-09-08 10:40:58 CREATE TABLE #T(a INT,b INT)
CREATE TABLE #TT(a INT,b INT)
INSERT INTO #T VALUES(1,1)
INSERT INTO #T VALUES(2,1)
INSERT INTO #TT VALUES(1,1)
INSERT INTO #TT VALUES(1,2)
SELECT * FROM #T,#TT WHERE #T.A *=#TT.A AND COALESCE(#TT.B,0) - #T.B>0
DROP TABLE #T
DROP TABLE #TT
--结果应该只有一条的