Re: BUG #8656: Duplicate data violating unique constraints

On 2013-12-04 20:04:15 +0000, maciek@heroku.com wrote:
> Bug reference:      8656
> Logged by:          Maciek Sakrejda
> Email address:      maciek@heroku.com
> PostgreSQL version: 9.3.1
> Operating system:   Ubuntu 12.04 LTS 64-bit
> Description:
>
> A customer has run into an issue where data in a single table was apparently
> duplicated somehow, violating the unique constraint imposed by the primary
> key:

This quite possibly is an instance of the second item mentioned on
http://www.postgresql.org/docs/devel/static/release-9-3-2.html (upcoming
release). Note that, due to time constraints, the fix isn't perfect, but
it will prevent that sort of issue.

Did you ever do a VACUUM FREEZE? Do you have significant concurrency?
Could you please send the output of pg_controldata and SELECT
relfrozenxid, relminmxid FROM pg_class WHERE oid =
'tablename'::regclass;?

Greetings,

Andres Freund

--
 Andres Freund                       http://www.2ndQuadrant.com/
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