Re: Temporary tables versus wraparound... again - Mailing list pgsql-hackers

From Andres Freund
Subject Re: Temporary tables versus wraparound... again
Date
Msg-id 20221206185905.kxvrnvso34pyw7yf@awork3.anarazel.de
Whole thread Raw
In response to Re: Temporary tables versus wraparound... again  (Greg Stark <stark@mit.edu>)
Responses Re: Temporary tables versus wraparound... again  (Greg Stark <stark@mit.edu>)
List pgsql-hackers
Hi,

On 2022-12-06 13:47:39 -0500, Greg Stark wrote:
> So.... I talked about this patch with Ronan Dunklau and he had a good
> question.... Why are we maintaining relfrozenxid and relminmxid in
> pg_class for temporary tables at all? Autovacuum can't use them and
> other sessions won't care about them. The only session that might care
> about them is the one attached to the temp schema.

Uh, without relfrozenxid for temp tables we can end up truncating clog
"ranges" away that are required to access the temp tables. So this would
basically mean that temp tables can't be used reliably anymore.

Greetings,

Andres Freund



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