From: guyren@relevantlogic.com <guyren@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-docs@lists.postgresql.org
Subject: Re: No discussion of custom variables; no "See also" for set_config, current_setting, pg_settings
Date: Fri, 2 Sep 2022 15:28:19 -0700
Message-ID: <E77AD906-61BB-4191-8EA5-8DE00AF8DBC3@relevantlogic.com> (raw)
In-Reply-To: <1228416.1662156969@sss.pgh.pa.us>
References: <166215027042.1235918.13727650130980574270@wrigleys.postgresql.org>
<1228416.1662156969@sss.pgh.pa.us>
Thanks for the quick response.
It’s a clearly useful, simplifying feature. Unless it is likely to be removed at some point, I propose it should be documented and declared supported wherever relevant.
In any event, I am happy to prepare some documentation changes that mention these caveats, but I won’t if there is no chance of it being accepted. Are we totally opposed?
> On Sep 2, 2022, at 15:16 , Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
> PG Doc comments form <noreply@postgresql.org> writes:
>> A reader of this section
>> https://www.postgresql.org/docs/current/sql-set.html of the documentation
>> might be forgiven for thinking that Postgres does not support custom
>> variables.
>
> They are, in fact, *not* a supported feature. The only intended use
> of non-core GUCs was for extensions' parameters. People have abused the
> mechanism to create ad-hoc session variables, but we don't encourage it.
> The underlying code won't scale to large numbers of variables, there's
> no way to declare properties of such a variable in SQL, etc.
>
> There's been an ongoing effort to create a respectable substitute,
> but it still hasn't gotten across the finish line [1].
>
> regards, tom lane
>
> [1] https://commitfest.postgresql.org/39/1608/
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To: pgsql-docs@postgresql.org
Cc: guyren@gmail.com, tgl@sss.pgh.pa.us, pgsql-docs@lists.postgresql.org
Subject: Re: No discussion of custom variables; no "See also" for set_config, current_setting, pg_settings
In-Reply-To: <E77AD906-61BB-4191-8EA5-8DE00AF8DBC3@relevantlogic.com>
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