Re: Shaky coding for vacuuming partitioned relations

On Fri, Sep 29, 2017 at 12:43 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> If I understand correctly, problem #1 is that get_rel_oids() can emit
>> a user-visible cache lookup failure message. There is a proposed patch
>> by Michael Paquier which appears to implement the design suggested by
>> Tom. I think that the normal procedure would be for Tom to commit
>> that change if he's happy with it.
>
> Yes, I'm happy to take responsibility for this.

Great, thanks.

>> I don't think I understand problem #2. I think the concern is about
>> reporting the proper relation name when VACUUM cascades from a
>> partitioned table to its children and then some kind of concurrent DDL
>> happens, but I don't see a clear explanation on the thread as to what
>> exactly the failure scenario is, and I didn't see a problem in some
>> simple tests I just ran. Furthermore, it sounds like this might get
>> fixed as part of committing the patch to allow VACUUM to mention
>> multiple tables, which Tom has indicated he will handle.
>
> I think the conclusion was that this wouldn't actually happen in v10,
> but I will take a closer look and do something about it if it is possible.

Even better, thanks.

--
Robert Haas
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