From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alvaro Herrera <alvherre@commandprompt.com>
Cc: Arctic Toucan <arctic_toucan@hotmail.com>
Cc: pgsql-admin@postgresql.org
Subject: Re: Is it safe to reset relfrozenxid without using vacuum?
Date: Tue, 18 Nov 2008 13:07:16 -0500
Message-ID: <22056.1227031636@sss.pgh.pa.us> (raw)
In-Reply-To: <20081118162406.GD4141@alvh.no-ip.org>
References: <BAY126-W258E8EA30779618A479BFE9C120@phx.gbl>
<20081118162406.GD4141@alvh.no-ip.org>
Alvaro Herrera <alvherre@commandprompt.com> writes:
> AFAICS this should be safe. In fact, in 8.3 TRUNCATE advances
> relfrozenxid. (Perhaps you should consider upgrading if possible.)
> ...
> Tou could just obtain the xid of the transaction that's going to do the
> import (for example by creating a temp table and getting it's xmin from
> pg_class)
That seems a bit risky. 8.3 resets relfrozenxid to RecentXmin, not the
current transaction's XID. The OP's thought of taking the max existing
relfrozenxid should be safe though.
Or I guess you could make a temp table and take the relfrozenxid, rather
than the xmin, from its pg_class entry.
regards, tom lane
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To: pgsql-admin@postgresql.org
Cc: tgl@sss.pgh.pa.us, alvherre@commandprompt.com, arctic_toucan@hotmail.com
Subject: Re: Is it safe to reset relfrozenxid without using vacuum?
In-Reply-To: <22056.1227031636@sss.pgh.pa.us>
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