Date: Wed, 21 Jun 2006 13:33:05 -0500
From: "Jim C. Nasby" <jnasby@pervasive.com>
To: "Merkel Marcel (CR/AEM4)" <Marcel.Merkel@de.bosch.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Big array speed issues
Message-ID: <20060621183305.GB93655@pervasive.com>
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	<EA04C6394A303A4CADF281DE22F232A41D4359@si-mail48.de.bosch.com>
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On Wed, Jun 21, 2006 at 09:29:03AM +0200, Merkel Marcel (CR/AEM4) wrote:
>  
> 
> Von: Merlin Moncure [mailto:mmoncure@gmail.com] 
> An: Merkel Marcel (CR/AEM4)
> Cc: pgsql-performance@postgresql.org
> Betreff: Re: [PERFORM] Big array speed issues
> 
> On 6/20/06, Merkel Marcel (CR/AEM4) <Marcel.Merkel@de.bosch.com> wrote:
> 
> > I use libpqxx to access the database. This might be another
> bottleneck, but
> > I assume my query and table setup is the bigger bottleneck. Would it
> make
> > sense to fetch the whole array ? (Select map from table where ...  and
> parse
> > the array manually)
> 
> have you tried similar approach without using arrays?
> 
> Merlin
> 
> 
> Not yet. I would first like to know what is the time consuming part and
> what is a work around. If you are sure individual columns for every
> entry of the array solve the issue I will joyfully implement it. The
> downsize of this approch is that the array dimensions are not always the
> same in my scenario. But I have a workaround in mind for this issue.

Before mucking about with the code, I'd absolutely try 8.1. I've
generally seen it double the performance of 7.4.

Also, output from EXPLAIN ANALYZE would make it a lot easier to figure
out what the issue is, and it would be good to try this without
selecting any of the arrays.
-- 
Jim C. Nasby, Sr. Engineering Consultant      jnasby@pervasive.com
Pervasive Software      http://pervasive.com    work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf       cell: 512-569-9461