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

"Aasmund Midttun Godal" <postgresql@envisity.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