Re: [COMMITTERS] pgsql: Add support for REFRESH MATERIALIZED VIEW CONCURRENTLY.

On 2013-07-22 19:09:13 -0400, Tom Lane wrote:
> Andres Freund <andres@2ndquadrant.com> writes:
> > On 2013-07-17 10:11:28 -0400, Tom Lane wrote:
> >> The buildfarm members that use -DCLOBBER_CACHE_ALWAYS say this patch
> >> is broken.
> 
> > Jagarundi still tells that story.
> 
> Uh, no.  Jagarundi was perfectly happy for several build cycles after
> I committed 405a468.  The buildfarm history shows that it started
> complaining again after this change:
> 
> f01d1ae Add infrastructure for mapping relfilenodes to relation OIDs

Huh? That's rather strange. No code from that patch is even exececuted
until the alter_table regression tests way later. So I can't see how
that patch could cause the matview error. Which is pretty clearly using
an freed relcache entry.
I think this may be a timing issue.

> > At least something like the following patch seems to be required.
> 
> This does look like a necessary change, but I suspect there is also
> something rotten in f01d1ae.

The alter table failure lateron seems to be "ERROR:  relation "tmp"
already exists", which just seems to be a consequence of incomplete
cleanup due to the earlier crashes.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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