From: Tom Lane <tgl@sss.pgh.pa.us>
To: David Rowley <dgrowleyml@gmail.com>
cc: Nathan Bossart <nathandbossart@gmail.com>, 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.
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Comments: In-reply-to David Rowley <dgrowleyml@gmail.com>
	message dated "Thu, 16 Oct 2025 13:35:24 +1300"
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Date: Wed, 15 Oct 2025 20:45:47 -0400
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David Rowley <dgrowleyml@gmail.com> writes:
> On Thu, 16 Oct 2025 at 12:36, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> (Hmm ... but on the third hand, if we only need one of the
>> two strings, couldn't we mechanize that by wrapping the
>> pg_get_indexdef call in CASE WHEN c.contype IS DISTINCT FROM 'x'
>> ?)

> Unless I'm mistaken, it looks like the "indexdef" field is used only
> when there's no corresponding constraint with contype 'p,', 'u' or
> 'x'.

Ah.  I hadn't researched that, but it makes sense.

> Wouldn't it be more like:

> CASE WHEN c.conrelid IS NULL THEN
> pg_catalog.pg_get_indexdef(i.indexrelid) ELSE '' END AS indexdef

I'd leave out the ELSE so that you get a null if the function
isn't run, but yeah.  (The places saving these query results would
need PQgetisnull tests, too.)

			regards, tom lane