Re: Table has duplicate keys, what did I do

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: John Gateley <gateley@jriver.com>
Cc: pgsql-general@postgresql.org
Date: 2008-01-29T19:47:11Z
Lists: pgsql-general
John Gateley <gateley@jriver.com> writes:
> Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> There was a fix released in 8.1.9 for a problem that could cause VACUUM
>> FULL to create duplicate copies of a row that had recently been updated.
>> Does that sound like a plausible scenario for your usage?

> Yes, it does, very much so. The row in question is updated once
> a minute (it is "test" data that is used by our system monitor
> to ensure that the database is up, and one of the tests is updating
> the row), and the database is vacuumed full once a day.

Yeah, that fits exactly.  IIRC that VACUUM FULL bug could only be
triggered if there had been a series of multiple updates to the same row
within the lifespan of the oldest open transaction, so repeated updates
on a short timescale would form part of the triggering condition.

Sounds like you need to pester Ubuntu to freshen their package ...

			regards, tom lane