weixin_46696397的博客

--dense——rank()分析函数(查找每个部门工资最高前三名员工信息)select * from (select deptno,ename,sal,dense_rank() over (partition by deptno order by sal desc) a from scott(数据库表名)) where a<=3 order by deptno asc, sal desc; --rank()分析函数(运行结果与上句相同)select * from (select dep...