Message-ID: <45b3a1dd6be28dd409850a5503c029a97ca0754e.camel@cybertec.at>
Subject: Re: The ability of postgres to determine loss of files of the main
 fork
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Aleksander Alekseev <aleksander@tigerdata.com>, Frits Hoogland
	 <frits.hoogland@gmail.com>
Cc: pgsql-hackers@lists.postgresql.org
Date: Wed, 01 Oct 2025 08:26:50 +0200
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On Tue, 2025-09-30 at 18:55 +0300, Aleksander Alekseev wrote:
> > Therefore, I would like to request an enhancement: add an option to
> > verify_heapam() that causes the primary key index to be scanned and mak=
es
> > sure that all line pointers in the index point to existing tuples.
>=20
> I'm a bit puzzled by your emphasis on primary keys. In Postgres it is
> legal to have tables without PKs, indexes, or even columns:
>=20
> =3D# create table my_table();
> =3D# select * from my_table;
>=20
> To clarify, are you proposing not to check such tables?

If there is no index on a table, there is no way to determine a missing
segment.  I don't think that Frits deliberately wants to *not* check
such tables, it's just that there is no way to do it as things are now.

Just because a check is not possible in certain cases is no good reason
to forgo a check in those cases where it is possible.

Yours,
Laurenz Albe