Received: from maia.hub.org (maia-5.hub.org [200.46.204.29]) by mail.postgresql.org (Postfix) with ESMTP id 537A063380F for ; Mon, 28 Jun 2010 09:40:53 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.29]) (amavisd-maia, port 10024) with ESMTP id 61996-02 for ; Mon, 28 Jun 2010 12:40:45 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from jupiter.marktest.pt (delta.marktest.pt [80.251.174.116]) by mail.postgresql.org (Postfix) with ESMTP id 461826325DA for ; Mon, 28 Jun 2010 09:40:44 -0300 (ADT) Received: from Proteu (proteu.marktest.pt [10.61.90.54]) by jupiter.marktest.pt with SMTP (Microsoft Exchange Internet Mail Service Version 5.5.2653.13) id NR67F130; Mon, 28 Jun 2010 13:40:42 +0100 Message-ID: <10B2957382DB4803B59D6ECB7FBCA945@marktestcr.marktest.pt> From: "Oliveiros d'Azevedo Cristina" To: "ced" , References: <4C28736E.8030409@dreamgnu.com> <72B95859322043DF995F2012194B4754@marktestcr.marktest.pt> <4C288765.8080604@dreamgnu.com> Subject: Re: Outer join construction step :strange results Date: Mon, 28 Jun 2010 13:40:40 +0100 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="utf-8"; reply-type=original Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5512 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=1.229 tagged_above=-5 required=5 tests=BAYES_50=0.8, STOX_REPLY_TYPE=0.439, T_RP_MATCHES_RCVD=-0.01 X-Spam-Level: * X-Archive-Number: 201006/113 X-Sequence-Number: 34304 > Oliveiros d'Azevedo Cristina wrote: >> Howdy, Cedric . >> >> Before analysing this problem of yours further, I 'd like you to >> kindly clarify me some points, please >> >> >> >>> >>> I have table following tables T0,T1,T2,T3, T1T2 >>> with >>> -T0(id, fk_T1) >>> -T1(id ) >>> -T2(id, fk_T3) >>> -T1T2(fk_T1,fk_T2) >>> -T3 (id) >>> >>> The table T0 represents sets of T1 items. >>> The table T1 represents items. >>> The table T3 represents property types. >>> The table T2 represents represents property values of a specific type. >>> >> >> >> T0.id is not a primary key, is it? > all columns with id are Primary keys > all columns with fk_T1 are foreign keys Can you specify a little more how you represent T1 item sets with this data model? What exactly represents one row from table T0? A pair (id, fk_T1) ? A set with just one element? Best, Oliveiros