From: Tom Lane <tgl@sss.pgh.pa.us>
To: Nacho Caballero <nachocab@gmail.com>
cc: pgsql-bugs@lists.postgresql.org
Subject: Re: Bug in tzdata 2022g
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Comments: In-reply-to Nacho Caballero <nachocab@gmail.com>
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Nacho Caballero <nachocab@gmail.com> writes:
> There appears to be a bug in the latest postgres release, which uses tzdata
> 2022g to reflect the recent DST change in Mexico.

I see no bug here.  America/Mexico_City is reported as being -06
all year round, which agrees with what the tzdb commentary says:

# From Paul Eggert (2022-10-28):
# The new Mexican law was published today:
# https://www.dof.gob.mx/nota_detalle.php?codigo=5670045&fecha=28/10/2022
# This abolishes DST except where US DST rules are observed,
# and in addition changes all of Chihuahua to -06 with no DST.

Meanwhile, Bogota has been -05 year-round since the nineties.

If you disagree with either of these conclusions, you had better
provide some solid evidence to back it up; and the place to be
complaining to is the tzdata maintainers, not us.

> However, when I run it in PostgreSQL 12.10 (Ubuntu 12.10-1.pgdg20.04+1), I
> get the right answer (no time difference):

Apparently, your PG 12.10 installation is using some pre-2022f
version of tzdata.  Mexico didn't abolish DST until late last year.

			regards, tom lane