求oracle达人解决一个问题 不知道这个哪错了求帮助
select avg(sal),avg( nvl(comm,0)),job case when avg(nvl(comm,0))>300 then '奖金不错' when avg(nvl(comm,0))>100 and avg(nvl(comm,0))<=300 then'奖金一般' when avg(nvl(comm,0))<=100 then '几乎没有奖金' end 奖金状况 from emp group by job order by job desc,avg(sal) desc;