Minimum value row

Question

I have a table as follows
Temp
col1  col2 col3 col4
999   0909  1    a
999   0909  2     r
999   0202  1    aaa
999   0202  2    bbb
999   0303  2    khp
999   0303  3    lkp
999   0404  4    pppHow can I extract min(col3) row from temp.
Expected rows from the table
999   0909  1  a
999   0202  1  aaa
999   0303  2  khp
999   0404  4  pppPlease help

Answer 1

Hi,
Do you want
the lowest col3, and whatever value of col4 happens to be on the same row with the losest c3, or
the lowest col4, and whatever value of col3 happens to be on the same row with the losest c4? Solomon assumed this, so I will, too.
The results happen to be the same in the small set of sample data you posted.
What results would you want from these two additional rows?
select 999,'9876',2,'aaa' from dual union all
select 999,'9876',1,'zzz' from dual union all?
The solution Solomon posted (perhaps with col3 and col4 reversed) is perfect for the question you asked.
If you have several columns like col3, which are not involved in the decision about which rows to display, but have to be displayed, then you have to repeat the KEEP (DENSE_RANK stuff for every column. That can be tedious.
Here's another way that's good if you have a lot of columns in the row:
WITH     got_rnum     AS
     SELECT     t.*
     ,     RANK () OVER ( PARTITION BY  col1
                           ,          col2
                      ORDER BY          col4
                    )      AS rnum
     FROM     t
--     WHERE     ...     -- any filtering goes here
SELECT     *     -- or list all columns except rnum
FROM     got_rnum
WHERE     rnum     = 1
;Edited by: Frank Kulash on Dec 9, 2009 8:14 PM