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Date: Wed, 07 Mar 2012 06:35:03 -0800
From: Steve Crawford <scrawford@pinpointresearch.com>
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To: Lukasz Brodziak <lukasz.brodziak@gmail.com>
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Subject: Re: pg_attribute file in PostgreSQL 9.0
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On 03/07/2012 05:14 AM, Lukasz Brodziak wrote:
> Hello,
>
> I have a question regarding pg_attribute. In which file it is stored
> because the relfilenode for it shows 0 and file 1249 isn't present in
> the folder.
>
select pg_relation_filepath('pg_attribute');

 From the docs, relfilenode is:
"Name of the on-disk file of this relation; zero means this is a 
"mapped" relation whose disk file name is determined by low-level state"

However the meaning "mapped relation" and "low-level state" are 
difficult to divine from the docs. Go with the function.

Cheers,
Steve