Re: Vacuum/visibility is busted

Pavan Deolasee escribió:
> On Thu, Feb 7, 2013 at 2:25 PM, Pavan Deolasee <pavan.deolasee@gmail.com> wrote:
>
> >
> > Will look more into it, but thought this might be useful for others to
> > spot the problem.
> >
>
> And here is some more forensic info about one of the pages having
> duplicate tuples.
>
> jjanes=# select *, xmin, xmax, ctid from foo where index IN (select
> index from foo group by index having count(*) > 1 ORDER by index)
> ORDER by index LIMIT 3;
>  index | count |    xmin    | xmax |   ctid
> -------+-------+------------+------+-----------
>    219 |   353 | 2100345903 |    0 | (150,98)
>    219 |   354 | 2100346051 |    0 | (150,101)
>    219 |   464 | 2101601086 |    0 | (150,126)
> (3 rows)

Hm, if the foreign key patch is to blame, this sounds like these tuples
had a different set of XMAX hint bits and a different Xmax, and they
were clobbered by something like vacuum or page pruning.

--
Álvaro Herrera                http://www.2ndQuadrant.com/
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