Help: Limiting the number of rows returned.

I need limit the number of rows returned on a query, the table could hold millions of rows so we definetly do NOT want to return the entire table. The catch is, I need to select the last n records that were modified.

When I use rownum, it doesn't order the records properly. That is, if I issue a select using rownum, ordering by a date field, it does not get the last rows. It retrieves them and then does the order by. I need it to do the order by first.

ex: SQL> select ncsn,ncnumber,date_modified from nonconform where rownum < 20 and date_modified is not
  null order by date_modified desc;

Is there a way to do a select so that I will always get the correct rows? So that it orders the records, then retrieves the number of rows that I specify?

Oh yes, we're using Oracle 7.3.

Thanks,
  Rich W. Received on Tue Sep 29 1998 - 08:43:13 CDT