From oracle-l-bounce@freelists.org Mon Aug 8 09:05:37 2005 Return-Path: Received: from air891.startdedicated.com (root@localhost) by orafaq.com (8.12.10/8.12.10) with ESMTP id j78E5bvM002200 for ; Mon, 8 Aug 2005 09:05:37 -0500 X-ClientAddr: 206.53.239.180 Received: from turing.freelists.org (freelists-180.iquest.net [206.53.239.180]) by air891.startdedicated.com (8.12.10/8.12.10) with ESMTP id j78E5ZIP002176 for ; Mon, 8 Aug 2005 09:05:36 -0500 Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id E91461DD454; Mon, 8 Aug 2005 09:05:31 -0500 (EST) Received: from turing.freelists.org ([127.0.0.1]) by localhost (turing [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 17328-06; Mon, 8 Aug 2005 09:05:31 -0500 (EST) Received: from turing (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 6B7FC1DD4BE; Mon, 8 Aug 2005 09:05:31 -0500 (EST) In-Reply-To: To: jim_kennedy@mentor.com Cc: "Niall Litchfield" , oracle-l@freelists.org, oracle-l-bounce@freelists.org, psinger1@chartermi.net Subject: RE: Counterquestion - is Oracle a He or a She - or an It or a hermaphrodite MIME-Version: 1.0 Message-ID: From: "Leandro Guimaraes Faria C. Dutra" Date: Mon, 8 Aug 2005 10:59:37 -0300 X-MIMETrack: Serialize by Router on TDBKDD08/TDB(Release 6.5.1|January 21, 2004) at 08/08/2005 10:55:54 AM, Serialize complete at 08/08/2005 10:55:54 AM Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by Ecartis X-archive-position: 23545 X-ecartis-version: Ecartis v1.0.0 Sender: oracle-l-bounce@freelists.org Errors-To: oracle-l-bounce@freelists.org X-original-sender: ldutra@toyota.com.br Precedence: normal Reply-To: ldutra@toyota.com.br X-list: oracle-l X-Virus-Scanned: by amavisd-new-20030616-p9 (Debian) at avenirtech.net X-mailscan-MailScanner-Information: Please contact the ISP for more information X-mailscan-MailScanner: Found to be clean X-MailScanner-From: oracle-l-bounce@freelists.org X-Spam-Level: X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on air891.startdedicated.com X-Spam-Status: No, hits=-4.9 required=5.0 tests=AWL,BAYES_00 autolearn=ham version=2.63 oracle-l-bounce@freelists.org gravou em 2005-08-08 10:53:09: > Sorry if I wasn't clear enough. NULL!=NKA. They are very > different. NKA means the Dr. asked the question and the patient > said I don't have any allergies. (So they don't have any known > allergies. They still might be allergic to something, but there > aren't any known allergies.) > > So yes, if the person has one or more allergies there was an allergy > table. If they didn't have any known allergies NKA was one of the > entries on the allergy table. But if they hadn't been asked then > the key was NULL.(we don't know if they are or are not allergic to > anything and we have not asked them the question.) So that's a boolean: has the question been asked? Or a field stating where the information comes from with such a special value. No need for a generic, context-dependent NULL, nor for a special value in the allergy table -- perhaps I should clarify that, contrary to NULLs, special values are no crime; it is just that this specific one is not necessary in this case. It is OK for natural languages to be context dependent. Not so for a DB. -- Leandro Guimarães Faria Corcete DUTRA Administrador de Bases de Dados +55 (11) 4390 5383 Toyota do Brasil Ltda ldutra@toyota.com.br São Bernardo do Campo, SP BRASIL This message (including any attachments) is confidential and may be privileged and intended solely for the use of the person/entity to whom it is addressed. If you have received it by mistake please notify the sender by returning via e-mail as well as delete this message from your system. Any unauthorized use or dissemination of this message in whole or in part is prohibited. Please note that e-mails are susceptible to change. TOYOTA DO BRASIL LTDA (including its group companies) shall not be liable for the improper or incomplete transmission of the information contained in this communication, neither for personal, nonbusiness related information nor opinion sent through this email or even for any delay in its receipt or damage to your system. TOYOTA DO BRASIL LTDA (or its group companies) does not guarantee that the integrity of this communication has been kept nor that this communication is free of viruses, interceptions or interference. -- http://www.freelists.org/webpage/oracle-l