Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1sp5XS-00GPdY-71 for pgsql-general@arkaria.postgresql.org; Fri, 13 Sep 2024 12:36:39 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.94.2) (envelope-from ) id 1sp5XR-002FHA-G8 for pgsql-general@arkaria.postgresql.org; Fri, 13 Sep 2024 12:36:37 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1sp5XR-002FH2-44 for pgsql-general@lists.postgresql.org; Fri, 13 Sep 2024 12:36:37 +0000 Received: from mail.appl-ecosys.com ([50.126.108.78]) by magus.postgresql.org with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1sp5XJ-000zJw-Kz for pgsql-general@postgresql.org; Fri, 13 Sep 2024 12:36:36 +0000 Received: from salmo.appl-ecosys.com (salmo.appl-ecosys.com [192.168.55.1]) by mail.appl-ecosys.com (Postfix) with ESMTP id 60C512A14D6 for ; Fri, 13 Sep 2024 05:36:28 -0700 (PDT) Date: Fri, 13 Sep 2024 05:36:28 -0700 (PDT) From: Rich Shepard To: "pgsql-general@postgresql.org" Subject: Re: DDL issue In-Reply-To: Message-ID: References: <91bda8-3bdb-d93-6c17-41a03a3de27a@appl-ecosys.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8BIT List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk On Thu, 12 Sep 2024, David G. Johnston wrote: > Read up on “many-to-many” data models. In SQL they involve a linking > table, one row per bidirectional edge, in addition to the two node tables. David, Thanks very much. I knew about those a long time ago but haven't needed them in a long time so I forgot about them. Will re-learn. Much appreciated, Rich