From: Tom Lane <tgl@sss.pgh.pa.us>
To: =?UTF-8?Q?Umut_TEK=C4=B0N?= <umuttechin@gmail.com>
cc: david.g.johnston@gmail.com, pgsql-bugs@lists.postgresql.org
Subject: Re: Inconsistent 'at time zone' conversion
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	message dated "Mon, 20 Feb 2023 13:54:15 +0100"
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Date: Mon, 20 Feb 2023 10:05:49 -0500
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=?UTF-8?Q?Umut_TEK=C4=B0N?= <umuttechin@gmail.com> writes:
> So, it should be related to the date. Yet, as you can see '2004-10-19
> 10:23:54+03' is nearly the same time of the year 18 years and 4 months ago.
> So, the same DST rules should apply, but it does not.

It's folly to make such an assertion without having checked tzdb ;-).
DST laws change from time to time.

A bit of experimentation shows that Postgres does think both those
zones were observing DST on 2004-10-19, and I would be quite surprised
if it's wrong about that.  (Even if it's wrong, that would be tzdb's
bug not ours.)

			regards, tom lane