Received: from localhost (unknown [200.46.208.211]) by mail.postgresql.org (Postfix) with ESMTP id 3B87F632412 for ; Thu, 18 Jun 2009 12:32:18 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by localhost (mx1.hub.org [200.46.208.211]) (amavisd-maia, port 10024) with ESMTP id 01208-05 for ; Thu, 18 Jun 2009 12:32:16 -0300 (ADT) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail-pz0-f203.google.com (mail-pz0-f203.google.com [209.85.222.203]) by mail.postgresql.org (Postfix) with ESMTP id DACD0632335 for ; Thu, 18 Jun 2009 12:32:16 -0300 (ADT) Received: by pzk41 with SMTP id 41so1032535pzk.15 for ; Thu, 18 Jun 2009 08:32:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from :user-agent:mime-version:cc:subject:references:in-reply-to :content-type:content-transfer-encoding; bh=jPxIzBHyC3pXEwQ4gvEyihPu+ObxJcyq6YTlj8EuXtk=; b=QaPgApXPYGS/G9tD62NEVZrGBwOGMd9RRLNLR7Yth9y0ZxrXcem7sOLlXATblf1F0D P79+TS4BxWsgfQF9TmkWh9w1zpW7yUOBYDft93rtXKlKDJaH1x+86c/wWsJXaGJBGxzS 3Qnhl1SqYGvf4VaGBaimrgA/+T+Ijkrx8kfv4= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:cc:subject:references :in-reply-to:content-type:content-transfer-encoding; b=UP89vwL9PgNM25B8pwbjohX1K6pA1dRRTXA4xJKLLR9uAsaja/5e/EWcgLTn9EhZf3 gDGW4leAqvhyl7KPIawxAUdeFFS6/F1KkauQackCmGwIaMcbGt5gILTqagAQtQsLJphB doOxadjJRWYzpxSWE0oI+kPYiVXMnVHPi98MM= Received: by 10.142.14.18 with SMTP id 18mr1070409wfn.35.1245339135854; Thu, 18 Jun 2009 08:32:15 -0700 (PDT) Received: from ?172.16.1.220? ([208.187.158.94]) by mx.google.com with ESMTPS id 30sm591026wfd.21.2009.06.18.08.32.15 (version=TLSv1/SSLv3 cipher=RC4-MD5); Thu, 18 Jun 2009 08:32:15 -0700 (PDT) Message-ID: <4A3A5DF4.1090409@gmail.com> Date: Thu, 18 Jun 2009 09:32:04 -0600 From: Rob Sargent User-Agent: Thunderbird 2.0.0.21 (X11/20090318) MIME-Version: 1.0 CC: pgsql-sql@postgresql.org Subject: Re: 2 tables or two db? References: <1245338535.15412.4.camel@ivangeo> In-Reply-To: <1245338535.15412.4.camel@ivangeo> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0.936 tagged_above=0 required=5 tests=AWL=-0.645, MISSING_HEADERS=1.581 X-Spam-Level: X-Archive-Number: 200906/87 X-Sequence-Number: 32692 ivan marchesini wrote: > Dear postgres users, > > Suppose I have two tables of data. > > suppose the two table are really similar in dimensions > > suppose they will receive the same number and type of queries. > > in tems of performance (velocity of answer) it is better to place the > two tables in the same db or into two different db? > > may be it is a stupid question, but.... > > many many thanks... > > Ivan > > > > > My guess is that only physical separation will have any positive impact otherwise the two datasets are competing for the same resources. At least separate discs, controllers to avoid disc contention. Separate postgres instances to allow separate caches (in affect separate memory).