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Cc: pgsql-performance <pgsql-performance@postgresql.org>
Subject: Re: System tables screwed up? (WAS requested shared memory size
	overflows size_t)
From: Alvaro Herrera <alvherre@commandprompt.com>
To: Craig James <craig_james@emolecules.com>
In-reply-to: <4C23E93C.7010504@emolecules.com>
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Date: Thu, 24 Jun 2010 19:55:01 -0400
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Excerpts from Craig James's message of jue jun 24 19:24:44 -0400 2010:
> On 6/24/10 4:19 PM, Alvaro Herrera wrote:
> > Excerpts from Craig James's message of jue jun 24 19:03:00 -0400 2010:
> >
> >> select relname, pg_relation_size(relname) from pg_class
> >>           where pg_get_userbyid(relowner) = 'emol_warehouse_1'
> >>           and relname not like 'pg_%'
> >>           order by pg_relation_size(relname) desc;
> >> ERROR:  relation "rownum_temp" does not exist
> >>
> >> emol_warehouse_1=>  select relname from pg_class where relname = 'rownum_temp';
> >>          relname
> >> ----------------------
> >>    rownum_temp
> >> (1 row)
> >
> > What's the full row?  I'd just add a "WHERE relkind = 'r'" to the above
> > query anyway.
> 
> Thanks, in fact that works.  But my concern is that these are system tables and system functions and yet they seem to be confused.  I've used this query dozens of times and never seen this behavior before.  It makes me really nervous...

I think you're being bitten by lack of schema qualification.  Perhaps
you ought to pass pg_class.oid to pg_relation_size instead of relname.
What did you do to make pg_relation_size to work on type name?

Why is this a -performance question anyway?

-- 
Álvaro Herrera <alvherre@commandprompt.com>
The PostgreSQL Company - Command Prompt, Inc.
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