随笔分类 -  Oracle

摘要:1.NVL函数,用法:nvl(a,b)当第一个参数为空时,则显示第二个参数2.递归查询:connect by:一般用法:start with...connect by ... 例:select * from emp connect by mgr =prior empno start with emp 阅读全文
posted @ 2017-05-13 17:30 新晋超星星 阅读(322) 评论(0) 推荐(0)