Display top 5 highest salaries

Question

Hi all..
i need to retrieve the top 5 highest salaries from the emp table please help

Answer 1

An ORDER BY and ROWNUM in the same query don't do what you might think:
SQL> select empno, ename, sal
  2  from emp
  3  where rownum <= 5
  4  order by sal;
               EMPNO ENAME                       SAL
                7369 SMITH                       800
                7521 WARD                       1250
                7654 MARTIN                     1250
                7499 ALLEN                      1600
                7566 JONES                      2975
SQL> select empno, ename, sal
  2  from emp
  3  where rownum <= 5
  4  order by sal desc;
               EMPNO ENAME                       SAL
                7566 JONES                      2975
                7499 ALLEN                      1600
                7654 MARTIN                     1250
                7521 WARD                       1250
                7369 SMITH                       800These are neither the 5 highest or lowest sals.
That's because Oracle assigns rownum before the order by.
I would use dense_rank for this:
SQL> select *
  2  from
  3  (
  4     select empno, ename, sal
  5           ,dense_rank() over (order by sal desc) dr
  6     from   emp
  7     order  by sal desc
  8  )
  9  where dr <= 5;
               EMPNO ENAME                       SAL                   DR
                7839 KING                       5000                    1
                7788 SCOTT                      3000                    2
                7902 FORD                       3000                    2
                7566 JONES                      2975                    3
                7698 BLAKE                      2850                    4
                7782 CLARK                      2450                    5
6 rows selected.Of course, it depends on whether you want to count 3000 twice.
Message was edited by:
SomeoneElse