select count(*) Total,
sum(decode(extract(year from hiredate),'1980',1,0)) "1980",
sum(decode(extract(year from hiredate),'1981',1,0)) "1981",
sum(decode(extract(year from hiredate),'1982',1,0)) "1982",
......
from emp
也可以这样写：
select r,empno,ename,sal
from (select rownum r,empno,ename,sal
from (select rownum,empno,ename,sal from (select * from emp order by sal desc)
where rownum <=8) e1 ) e2
where r>=5
