[DB-SIG] DateTime: Changing the time value handling ?!

M.-A. Lemburg lemburg@uni-duesseldorf.de
Wed, 11 Mar 1998 16:23:38 +0100

Jim Fulton wrote:
> Greg Stein (Exchange) wrote:
> >
> The ODMG standard includes time zone in it's Time and Timestamp classes.
> They take a fairly minimalist approach.  Their time zones are just
> offsets
> from UTC.  They leave deciding *what* the offset is (e.g. dealing with
> daylight savings time) to the application.
> > I would highly recommend the absolute avoidance of anything that infers /
> > implies time zones within the base data types.
> I disagree with this statement, although not entirely.  As I have
> said before, I think the Date-Time classes should be based on the
> ODMG standard which provides a *mimimalish*, but useful, treatment
> of time zones.

I think Greg meant the low-level implementation of DateTime objects.

Time zone handling classes can be built on top of the basic types,
though it will certainly not be easy: there is no portable way of
getting the DST start/stop information, since the C API doesn't
export any of this information.

For details on an approach that works on some Unixes, see the 
Julian package on www.python.org in the contributed section.

There's also a tzparse.py file in the standard library that relies
on the environment variable TZ.

Marc-Andre Lemburg

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