Re: Error with implicit date calculation

On Feb 21, 12:14 am, Arch <send..._at_spam.net> wrote:
> On Wed, 20 Feb 2008 15:29:49 -0800, DA Morgan <damor..._at_psoug.org>
> wrote:
>
>
>
>
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> >Arch wrote:
> >> I need a hand with SQL. I'm using 9.2.0.4.
>
> >> I need to compute a date offset by a number of weeks from another
> >> date.  This is a line from a view that I had been using:
>
> >> TO_DATE('7-Dec-1998') + (WeekNum * 7) As WeekDate
>
> >> WeekNum is, of course, the field that contains the number of weeks to
> >> offset from the date.  This used to work just fine - it doesn't any
> >> longer.  The TO_DATE function now returns the error:
>
> >>      ORA_1858 a non-numeric character was found where a
> >>           numeric character was expected
>
> >> If I change it to TO_DATE('7-Dec-2000') or any later date, it no
> >> longer gives an error.  It does not return the desired value, of
> >> course, but no error.  Any date 1999 or earlier causes the error.
>
> >> I would appreciate any advice how to correct this.
>
> >It would likely help if you used the full syntax:
>
> >TO_DATE('07-DEC-1998', 'DD-MON-RRRR')
> >or
> >TO_DATE('07-DEC-1998', 'DD-MON-YYYY')
>
> Thank you.- Hide quoted text -
>
> - Show quoted text -

Yes, I was going to ask what the nls_date_format was set to since the default is for a 2 digit year. I have found it is always better to write code that uses the to_date function with a format mask specific to the application logic. That way when someone changes the session or worse system parameters your code is much more likely to continue to function correctly.

HTH -- Mark D Powell -- Received on Thu Feb 21 2008 - 15:12:14 CST