=?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