How to select recent date from a paricular row?

Question

Hi,
i am having a table below:
DATE_TABLE
ID DATE1 DATE2 DATE3
1 01-OCT-2011 01-NOV-2011 01-SEP-2011
2 01-JAN-2011 01-NOV-2011 25-NOV-2011
3 27-JAN-2011 01-MAY-2010 NULL
I NEED BELOW OUTPUT USING QUERY
OUTPUT
ID RECENT_DATE
1 01-NOV-2011
2 25-NOV-2011
3 27-JAN-2011
Edited by: Rajiv-883452 on Nov 29, 2011 12:15 PM

Answer 1

But it's not working for the NULL values, you'll need to NVL the columns that can have NULL's :
SQL> -- generating sample data:
SQL> with t as (
  2  select 1 id, to_date('01-OCT-2011', 'dd-mon-yyyy') dt1, to_date('01-NOV-2011', 'dd-mon-yyyy') d
t2, to_date('01-SEP-2011', 'dd-mon-yyyy') dt3 from dual union
  3  select 2, to_date('01-JAN-2011', 'dd-mon-yyyy'), to_date('01-NOV-2011', 'dd-mon-yyyy'), to_date
('25-NOV-2011', 'dd-mon-yyyy') from dual union
  4  select 3, to_date('27-JAN-2011', 'dd-mon-yyyy'), to_date('01-MAY-2010', 'dd-mon-yyyy'), to_date
(NULL) from dual
  5  )
  6  --
  7  -- actual query:
  8  --
  9  select id
10  ,      greatest(dt1,dt2,dt3)
11  from   t;
        ID GREATEST(
         1 01-NOV-11
         2 25-NOV-11
         3
SQL> -- generating sample data:
SQL> with t as (
  2  select 1 id, to_date('01-OCT-2011', 'dd-mon-yyyy') dt1, to_date('01-NOV-2011', 'dd-mon-yyyy') d
t2, to_date('01-SEP-2011', 'dd-mon-yyyy') dt3 from dual union
  3  select 2, to_date('01-JAN-2011', 'dd-mon-yyyy'), to_date('01-NOV-2011', 'dd-mon-yyyy'), to_date
('25-NOV-2011', 'dd-mon-yyyy') from dual union
  4  select 3, to_date('27-JAN-2011', 'dd-mon-yyyy'), to_date('01-MAY-2010', 'dd-mon-yyyy'), to_date
(NULL) from dual
  5  )
  6  --
  7  -- actual query:
  8  --
  9  select id
10  ,      greatest(dt1,dt2,nvl(dt3, to_date('01-JAN-1000','dd-mon-yyyy')))
11  from   t;
        ID GREATEST(
         1 01-NOV-11
         2 25-NOV-11
         3 27-JAN-11