From: Tom Lane <tgl@sss.pgh.pa.us>
To: Tomas Vondra <tomas@vondra.me>
cc: Bram van der Vos <bram.van.der.vos@axisinto.nl>,
        pgsql-bugs@lists.postgresql.org
Subject: Re: file corruption goes undetected
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 <9abdddef-4c08-4d47-8879-9265e164dacb@vondra.me>
Comments: In-reply-to Tomas Vondra <tomas@vondra.me>
	message dated "Fri, 07 Aug 2026 00:01:33 +0200"
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Tomas Vondra <tomas@vondra.me> writes:
> This is expected behavior, not a bug. It'd be great to detect these
> kinds of data corruption, but data checksums can't do that (and we don't
> have other protections).

I suspect what's really happening in this example is that the query
result is produced entirely from pages in shared buffers, so we don't
notice that the underlying disk files have been clobbered.  We would
notice once we have occasion to actually read the junk data.

			regards, tom lane