Re: Using xmin to identify last modified rows

From: "Stéphane A(dot) Schildknecht" <stephane(dot)schildknecht(at)postgresqlfr(dot)org>
To: pgsql-general(at)postgresql(dot)org
Subject: Re: Using xmin to identify last modified rows
Date: 2009-02-25 15:07:22
Message-ID: 49A55EAA.8040001@postgresqlfr.org
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Gregory Stark a écrit :
> "Stéphane A. Schildknecht" <stephane(dot)schildknecht(at)postgresqlfr(dot)org> writes:
(...)
>
> You could order by age(xmin) instead
>
>> What would be the best way to get last modified rows?
>
> I'm not sure using xmin is such a great idea really. It's handy for ad-hoc
> queries but there are all kinds of cases where it might not give you the
> results you expect.
>
> You probably want to put a timestamp column on your tables and manage the date
> you put in their according to a policy you control.
>
>

Gregory,

Thanks for the answer.

A timestamp would surely be a better idea. BTW, I don't have hand on the schema
yet and was just looking for a quick way to get some last modified rows.

Regards,
- --
Stéphane Schildknecht
PostgreSQLFr - http://www.postgresql.fr
Dalibo - http://www.dalibo.com
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