Re: problem with timezone parsing

On Mon, Feb 16, 2009 at 10:36:34AM +0100, Federico Di Gregorio wrote:

> > > > PostgreSQL (on Debian/Lenny) comes with a bunch of time
> > > > zones which psycopg2 cannot parse, such as Asia/Calcutta.
> > > > Attempts to read a "timestamp with time zone" column with
> > > > client timezone set to one of those zones throw an "unable
> > > > to parse time" exception. Strangely enough, Asia/Colombo,
> > > > which has the same utc offset (05:30:00) parses just fine.
> > > >
> > > > The corresponding time zones can be found with the attached
> > > > script (make sure to adjust the DSN).
> > > >
> > > > That script also reports another category of time zones
> > > > which PostgreSQL includes but cannot use ;-)   But that's
> > > > beyond the scope of psycopg2.
> > > 
> > > By any chance are the problem dates fairly old?
> > 
> > If "1920" is "fairly old", then, yes.
> > 
> > Examples are the dates of birth of some people living
> > today. This is a patient database (www.gnumed.de).
> 
> I agree with you that we need a way to recover from such errors

Great !

> but I
> don't know if raising an exception is enough. If the error generates (or
> propagates) to PostgreSQL then the current transaction is aborted and
> this probably something you don't want.

"generated by PostgreSQL" - no, the problem arises in
psycopg2 code, PG itself is just fine with those time zones

"propagate to PostgreSQL" - well, if I *don't* handle the
exception then it seems quite OK to me if PostgreSQL
transactions are affected - should the exception somehow
propagate into PG (how ?)

Karsten
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