From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
cc: Andres Freund <andres@anarazel.de>, pgsql-hackers@lists.postgresql.org
Subject: Re: pgsql: Prevent instability in contrib/pageinspect's regression
 test.
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
	message dated "Mon, 21 Nov 2022 12:52:01 -0500"
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Date: Mon, 21 Nov 2022 13:08:58 -0500
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Robert Haas <robertmhaas@gmail.com> writes:
> On Mon, Nov 21, 2022 at 12:35 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Hmm, so the problem is:
>> 
>> SELECT octet_length(get_raw_page('test1', 'main', 0)) AS main_0;
>> ERROR:  cannot access temporary tables during a parallel operation
>> 
>> Why in the world is get_raw_page() marked as parallel safe?
>> It clearly isn't, given this restriction.

> I suspect that restriction was overlooked when evaluating the marking
> of this function.

So it would seem.  PARALLEL RESTRICTED should work, though.

I'll check to see if any sibling functions have the same issue,
and push a patch to adjust them.

Presumably the parallel labeling has to be fixed as far back as
it's marked that way (didn't look).  Maybe we should push the
test change further back too, just to exercise this.

			regards, tom lane