From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Eisentraut <peter@eisentraut.org>
Cc: Navrátil, Ondřej <onavratil@monetplus.cz>
Cc: pgsql-docs@lists.postgresql.org
Subject: Re: COALESCE documentation
Date: Wed, 03 Jul 2024 10:57:48 -0400
Message-ID: <3251851.1720018668@sss.pgh.pa.us> (raw)
In-Reply-To: <62f888dc-1ee5-48cf-b76c-6a75dcfa8b10@eisentraut.org>
References: <CAEELDaqnn5GayihUUhnKLR1_fegb-_b2i+4_dP4U192uK7j9vw@mail.gmail.com>
<62f888dc-1ee5-48cf-b76c-6a75dcfa8b10@eisentraut.org>
Peter Eisentraut <peter@eisentraut.org> writes:
> I think this is actually a bug in the implementation, not in the
> documentation. That is, the implementation should behave like the
> documentation suggests.
The trouble with that is that it presumes that the standard's
definition of IS NOT NULL is not broken. I think it *is* broken
for rowtypes; it certainly cannot be claimed to be intuitive.
We already have disclaimers about that in our documentation
about IS [NOT] NULL. I don't really want to propagate similar
confusion into COALESCE, much less everyplace else that this'd
matter.
Having said that, I'm not sure that substituting "is distinct from
null" in the COALESCE documentation is much better, because it's not
clear to me that we're entirely standards-compliant about what that
means for rowtypes either.
regards, tom lane
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-docs@postgresql.org
Cc: tgl@sss.pgh.pa.us, peter@eisentraut.org, onavratil@monetplus.cz, pgsql-docs@lists.postgresql.org
Subject: Re: COALESCE documentation
In-Reply-To: <3251851.1720018668@sss.pgh.pa.us>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox