Keep Dense_rank() Last

Question

I am using said function in my query
SQL> select job,  max(hiredate) keep (dense_rank last order by hiredate) Hdate from emp
  2  group by job
  3  ;
JOB       HDATE
ANALYST   19-APR-87
CLERK     23-MAY-87
MANAGER   09-JUN-81
PRESIDENT 17-NOV-81
SALESMAN  28-SEP-81Can I use here Dense_rank second last () here ?
I I want to fetch second last record instead of Last record what should I do?
kindly help.
OR
I have another Query
SQL>  select job,hiredate,rn from (
  2   select job,  hiredate, dense_rank() Over (order by hiredate) Rn
  3   from emp)
  4   where rn <= 7
  5  /
JOB       HIREDATE          RN
CLERK     17-DEC-80          1
SALESMAN  20-FEB-81          2
SALESMAN  22-FEB-81          3
MANAGER   02-APR-81          4
MANAGER   01-MAY-81          5
MANAGER   09-JUN-81          6
SALESMAN  08-SEP-81          7
7 rows selected.Is this possible that I can calculate Last Two Date Difference of Job wise.
Like Salesman has 2 records hiredate 20-feb-81 and 22-feb-81 I want to calculate last 2 date difference.
other example
Manager Has 3 records Last 2 dates are 01-May-81 and 09-Jun-81 so calculate the difference.
Edited by: 867210 on Jul 6, 2011 4:06 AM

Answer 1

867210 wrote:
Can I use here Dense_rank second last () here ?You could specify only FIRST or LAST here.
Though there are other methods available to get the "second last" hiredate.
SQL> SELECT job,
  2         hiredate
  3  FROM   (SELECT job,
  4                 hiredate,
  5                 Dense_rank() OVER(PARTITION BY job ORDER BY hiredate DESC) dr
  6          FROM   emp)
  7  WHERE  dr = 2  ;
JOB       HIREDATE
ANALYST   03-DEC-81
CLERK     23-JAN-82
MANAGER   01-MAY-81
SALESMAN  08-SEP-81
4 rows selected.