Date/Time Field but not a date field type..

Question

I am dealing with a table that was already created and filled/filling with data.. so don't have an option to have someone go back and fix.
The field i am dealing with is a varchar2 not a date field.
it has values like
12/31/1899
2/17/2010 10:00:00 AM
2/24/2010 9:00:00 AM
2/17/2010 8:30:00 AM
2/24/2010 9:00:00 AM
12/31/1899
Basically the 12/31/1899 dates are supplied the data source as an indicator that the real date/time is unknown until it gets updated later in the day or next day. (why its like this i don't know)
anyways.. I need to drop records that are 7 days old.
So for say the 2/17/2010 ones, when its 2/24/2010 when the process is ran, those records will get deleted but with the '12/31/1899' ones staying as they are awaiting to be given a date/time '12/31/1899' date is always used for the 'unknowns' so that is constant. The other 'valid ones' always have a date and a time given.
I've tried a few things today, but kept blowing up.
Edited by: CPSteven on Feb 11, 2010 6:04 PM

Answer 1

>
ORA-01830: date format picture ends before converting entire input string
With that command
The time in their messing with it?
>
You'd have that problem if the date format picture ends before any of your your strings end....
Eg.. your date field has "time component" and you just use... "DD-MON-YYYY" as the format picture.
However, If your format picture includes the maximum possible detail (of any of your strings) , you'll not see that error. Check this code below.
sql> select * from temp;
        ID DATE_STRING
         1 02/11/2010 03:10:26
         2 02/10/2010 03:10:26
         3 02/09/2010 03:10:26
         4 02/08/2010 03:10:26
         5 02/07/2010 03:10:26
         6 02/06/2010 03:10:26
         7 02/05/2010 03:10:26
         8 02/04/2010 03:10:26
         9 02/03/2010 03:10:26
        10 02/02/2010 03:10:26
        11 12/31/1899
        ID DATE_STRING
        12 12/31/1899
12 rows selected.
sql> delete from temp
  2  where date_string != '12/31/1899'
  3    and to_date(date_string,'MM/DD/YYYY') < (sysdate-7);
  and to_date(date_string,'MM/DD/YYYY') < (sysdate-7)
ERROR at line 3:
ORA-01830: date format picture ends before converting entire input string
sql> delete from temp
  2    where date_string != '12/31/1899'
  3      and to_date(date_string,'MM/DD/YYYY HH24:MI:SS') < (sysdate-7);
4 rows deleted.
----In your case.. your format mask would be to_date(date_string,'MM/DD/YYYY HH:MI:SS AM')