--相当于建了个e临时表 with e as (select * from scott.emp e where e.empno=7499) select * from e; minus 取差集 可以替换(not in | in ) select id from order minus select order_id from order_detail
oracle 小技巧
原文：http://www.cnblogs.com/jayGold/p/4642750.html
