摘要: 注意ON关联值不能重复。SELECT A.A1,A.A2,B.B1,B2 FROM TABLEA ALEFT JOIN TABLEB BON A.A1 = B.B1WHERE A.A2 IS NULL AND B.B2 IS NOT NULL-----------------------------... 阅读全文
posted @ 2012-10-09 18:44 VipSoft 阅读(3967) 评论(0) 推荐(0)