From: Tom Lane <tgl@sss.pgh.pa.us>
To: Nathan Bossart <nathandbossart@gmail.com>
cc: andrewbille@gmail.com, pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #19086: pg_dump --data-only selects and do not uses index
 definitions for the dumped tables.
In-reply-to: <aO6mUj9H2WpEFylG@nathan>
References: <19086-871ff11017d03dc5@postgresql.org> <aO6mUj9H2WpEFylG@nathan>
Comments: In-reply-to Nathan Bossart <nathandbossart@gmail.com>
	message dated "Tue, 14 Oct 2025 14:36:50 -0500"
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Date: Tue, 14 Oct 2025 15:50:15 -0400
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Nathan Bossart <nathandbossart@gmail.com> writes:
> On Tue, Oct 14, 2025 at 08:13:52AM +0000, PG Bug reporting form wrote:
>> In case of system indexes corruption the collecting of index definition=
s can
>> take a really long time.

> I don't think this qualifies as a bug, but avoiding pg_dump queries when
> possible seems like a good idea.  Is this a hypothetical problem or
> something you've experienced?

Even if it's been seen in the field, it hardly qualifies as a
justification for complicating pg_dump's behavior.  There's no reason
to think that catalog corruption preferentially affects indexes, or
does so in this particular way.  Should we also not collect data on
functions, types, etc etc?

> Also, we need to be certain that nothing getIndexes() gathers is ever us=
ed
> for --data-only dumps.  That seems plausible, but I haven't looked close=
ly.

Yeah, that's the main thing I'd worry about here.  For example,
ignoring some objects would likely lead to different conclusions about
the database objects' dependency web, possibly leading to changes in
dump order or other effects.  Maybe there's no problem in practice,
but this unsupported bug report doesn't really motivate me to do the
analysis to see if it'd be all right.

			regards, tom lane