Re: VACUUM and open transactions - Mailing list pgsql-general

From Alvaro Herrera
Subject Re: VACUUM and open transactions
Date
Msg-id 20070131015519.GD2178@alvh.no-ip.org
Whole thread Raw
In response to Re: VACUUM and open transactions  (Joseph S <jks@selectacast.net>)
Responses Re: VACUUM and open transactions  (Joseph S <jks@selectacast.net>)
List pgsql-general
Joseph S wrote:
> I realize this thread is old, but I just conducted an experiment with pg
> 8.0.10 and a transaction with a SERIALIZABLE isolation level does
> prevent VACUUM from reclaiming rows that were created and then obsoleted
>  in a subsequent transaction.

Right.  This is expected.  VACUUM cannot remove them because the
serializable transaction might still want to see those rows.  (I am
assuming the serializable transaction is still running when the vacuum
starts.  If that's not the case, please explain better).

--
Alvaro Herrera                                http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support

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