Received: from localhost (unknown [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id 8E6A164FCEA for ; Wed, 3 Sep 2008 05:59:10 -0300 (ADT) Received: from postgresql.org ([200.46.204.86]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 64460-04 for ; Wed, 3 Sep 2008 05:59:01 -0300 (ADT) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail.gmx.net (mail.gmx.net [213.165.64.20]) by postgresql.org (Postfix) with SMTP id 60E6864FFB2 for ; Wed, 3 Sep 2008 05:58:59 -0300 (ADT) Received: (qmail 14547 invoked by uid 0); 3 Sep 2008 08:58:55 -0000 Received: from 192.124.237.8 by www139.gmx.net with HTTP; Wed, 03 Sep 2008 10:58:55 +0200 (CEST) Content-Type: text/plain; charset="us-ascii" Date: Wed, 03 Sep 2008 10:58:55 +0200 From: "Jan-Peter Seifert" Message-ID: <20080903085855.311500@gmx.net> MIME-Version: 1.0 Subject: dblink /synonyms? To: pgsql-performance@postgresql.org X-Authenticated: #955937 X-Flags: 0001 X-Mailer: WWW-Mail 6100 (Global Message Exchange) X-Priority: 3 X-Provags-ID: V01U2FsdGVkX1+7gwgxOgO7S7l7ziUToeN2zwgMpc/k8KnpQ/asff UksetlV5SkGj52K7+Um+hEXt2BnU35UC9JBg== Content-Transfer-Encoding: 7bit X-GMX-UID: mDTMaMoYeSEqVUD1ZXQhSfJ+IGRvb4BJ X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0 tagged_above=0 required=5 tests=none X-Spam-Level: X-Archive-Number: 200809/44 X-Sequence-Number: 31357 Hello, we had problems with queries via dblink needing more than three times as long as without dblink on the same server. This has been tested with v8.3.3 as well. Is this still an issue?: http://cunha17.cristianoduarte.pro.br/postgresql/snapshots.en_us.php "But the two suffer from a severe problem: they bring the whole result from the remote query into the local database server. " Is anybody maintaining dblink (who?)? Are there other solutions for connecting two dbs in the work (like synonyms)? There is another "problem". It's difficult to compare the performance of the queries because the server is caching the queries and dblink is using the same cached querie results as well. Can you 'flush' the results or prevent the results from being cached for being reused? Is Explain Analyze really 'stable' for comparing purposes? Thank you very much, Peter -- Ist Ihr Browser Vista-kompatibel? Jetzt die neuesten Browser-Versionen downloaden: http://www.gmx.net/de/go/browser