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Date: Mon, 3 Feb 2025 17:21:41 +0100
From: =?utf-8?Q?=C3=81lvaro?= Herrera <alvherre@alvh.no-ip.org>
To: Robert Treat <rob@xzilla.net>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Laurenz Albe <laurenz.albe@cybertec.at>,
	bristleconeweb@gmail.com, pgsql-docs@lists.postgresql.org
Subject: Re: timestamp with time zone ~> GMT
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On 2025-Feb-03, Robert Treat wrote:

> This does seem to come up often enough that it probably is worth being
> a bit more explicit about how this works; attached patch attempts
> that.

LGTM.

> Note, I dropped the bit about GMT; that change was made ~40 years ago,
> and I suspect it is close to noise for many people these days, though
> it could be added back if folks feel strongly about it.

I don't feel strongly about it, but another option might be to add a
<footnote> so that it is still there but less intrusive.  Grepping for
GMT in the postgres repo there are still over 1400 matches of all kinds.

> As Tom notes above, what to store is debatable, and generally seems to
> conflate storage and display desires together, which makes it hard to
> imagine a generic enough implementation to put into core, but there
> are some attempts to solve this problem floating around in extension
> land. See https://github.com/mweber26/timestampandtz/blob/master/README.md
> as one such attempt.

Another simple option is to store a timezone name in a separate column,
which you can then use in the AT TIME ZONE clause.  This is of course
more wasteful than storing a 2-byte zone identifier as the
timestampandtz extension does.

-- 
Álvaro Herrera               48°01'N 7°57'E  —  https://www.EnterpriseDB.com/
Voy a acabar con todos los humanos / con los humanos yo acabaré
voy a acabar con todos (bis) / con todos los humanos acabaré ¡acabaré! (Bender)