Re: pg_autovacuum crashes when query fails for temp

matthew(at)zeut(dot)net ("Matthew T. O'Connor") wrote:
>> Bruce Momjian wrote:
>> Should pg_autovacuum be vacuuming temporary tables?
>
> This is a good question, and I would like some opinions from some other
> people more informed than I.
>
>> Secondly, why would
>> a temporary table for another session be visible to pg_autovacuum? I
>> know these may sound like stupid questions, but I'm a little shocked
>> that it found a temp table. Did someone make a permanent table, delete
>> it, and pg_autovacuum found it in between those operations?
>
> I will look into this when I have time, it certainly would be possible
> that pg_autovacuum could be tripped up by a sequence of events like you
> describe above. The more general problem is that it shouldn't crash even
> if it's vacuuming tables it shouldn't.

Well, there's an entry in pg_class even for temporary tables; that
means that even though a separate session has no ability to vacuum the
table, there is still a way to get at its name.

I would think that temp tables are TERRIBLE candidates for
auto-vacuuming; they are likely to be created via INSERT or SELECT
INTO, and if there is a need to analyze such a table, it is likely
needful to do so under strict application control.
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