Re: [SQL] Unpredictable text -> date implicit casting behaviour/to_date bug

On Mon, Dec 31, 2001 at 11:02:47AM -0500, Tom Lane wrote:
> "Aasmund Midttun Godal" <postgresql(at)envisity(dot)com> writes:
> > The implicit casting of text to date is normally quite good, however i
> > think it should only use one method during a given query (or maybe
> > transaction?)
>
> Try setting DateStyle to match the date style you are using. Postgres
> is doing the best it can with ambiguous input.
>
> > Added to the fact that to_date has a bug:
>
> > SELECT ordredato, ordredato::date, to_date(ordredato, 'DD.MM.YY') from old_faktura where status = 'ANN';
> > ordredato | ?column? | to_date
> > -----------+------------+---------------
> > 18.04.00 | 2000-04-18 | 0001-04-18 BC
> > 30.08.01 | 2001-08-30 | 2001-08-30
> > 18.04.00 | 2000-04-18 | 0001-04-18 BC
>
> I agree, this is not desired behavior. The problem seems to be that the
> logic in to_timestamp() tries to use "field is not zero" as a substitute
> test for "field was provided". At least in the case of the year fields,
> this is *not* workable. There must be a separate flag bit.
>
> regards, tom lane

Nice bug :-(

It's fixed and the patch is attached, please apply it to 7.2.

Thanks for report.

Karel

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Karel Zak <zakkr(at)zf(dot)jcu(dot)cz>
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