oracle Between 问题

我想查找 EMP 表中 3 到 9 行的数据

select * from emp where rownum between 3 and 9;

但是不可以

为什么 1到8 行就可以了

select * from emp where rownum between 1 and 8;

select * from emp e where e.rownum between 3 and 9;

因为rownum 字段是你查询到数据后生成的字段

select * from(select 列1,列2,列3...., rownum as rn from 表) where rn between 3 and 8;

把需要的列名在子查询中写出来