From oracle-l-bounce@freelists.org Mon Aug 8 07:31:48 2005 Return-Path: Received: from air891.startdedicated.com (root@localhost) by orafaq.com (8.12.10/8.12.10) with ESMTP id j78CVm2c018338 for ; Mon, 8 Aug 2005 07:31:48 -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 j78CVZIP018296 for ; Mon, 8 Aug 2005 07:31:35 -0500 Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id A0BAD1DD310; Mon, 8 Aug 2005 07:29:24 -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 02077-10; Mon, 8 Aug 2005 07:29:24 -0500 (EST) Received: from turing (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 1A82A1DCA26; Mon, 8 Aug 2005 07:29:24 -0500 (EST) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:references; b=izfXVeUFmo85iVRk3+MqN44hwsmin0VI8G58+lWaxL8opTgHeKQnC2oraM2HeEzBS9IeaKZpWc5Gh8bWT53ICaoS/YlwnfeZmc24eL0sHVje30VIeaIh7hjRhsOJKtbUArb9IwH6VhWEJ9zI1y+oVKQzS56wdcAdJ/l7REQEbPw= Message-ID: <7765c897050808052732e9d7f3@mail.gmail.com> Date: Mon, 8 Aug 2005 13:27:29 +0100 From: Niall Litchfield To: jim_kennedy@mentor.com Subject: Re: Counterquestion - is Oracle a He or a She - or an It or a hermaphrodite Cc: psinger1@chartermi.net, oracle-l@freelists.org In-Reply-To: Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_4084_4946148.1123504049240" References: X-archive-position: 23529 X-ecartis-version: Ecartis v1.0.0 Sender: oracle-l-bounce@freelists.org Errors-To: oracle-l-bounce@freelists.org X-original-sender: niall.litchfield@gmail.com Precedence: normal Reply-To: niall.litchfield@gmail.com 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=-2.9 required=5.0 tests=AWL,BAYES_00,HTML_MESSAGE autolearn=ham version=2.63 ------=_Part_4084_4946148.1123504049240 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Comments below On 8/6/05, Kennedy, Jim wrote:=20 >=20 >=20 >=20 > I explain NULLS in the following manner. >=20 > Imagine a medical application where your medical data is stored in a > database. Imagine that your Dr. has never asked you if you have > allergies or not. Further imagine that you become unconcouse and go to > the emergency room. The Dr. in the emergency room looks at your > electronic medical data. Given the information in your electronic chart > what should the Dr. assume about your allergic reactions?: > A. You are Alergic to something. > B. You are not allergic to anything. > C. It is unknown if you are or are not allergic to anything. >=20 > The Dr. should assume C. You have not been asked the question so the > data in that column is NULL and the Dr. should make NO assumptions about > your medical condition visa vis allergys. In medicine even if they > asked you the question "Are you allergic to anything?" and you answered > "No" the correct value to store is NKA - No Known Allergies. After > this explanation most people understand what a NULL is. > Jim Isn't this a great example of how a better design is a better solution?=20 Wouldn't=20 PATIENT =3D=3D=3D=3D=3D=3D=3D PATIENT_PK .................... ALLERGEN =3D=3D=3D=3D=3D=3D=3D=3D=3D ALLERGEN_PK ........................ KNOWN_ALLERGIES =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D PATIENT_PK -- foreign key ALLERGEN_PK -- foreign key IDENTIFIED_DATE ..... Be a better design? Then the doctor would just pull up a list of known=20 allergies (which might of course be empty). This is a lot different, and I'= d=20 argue better, than pulling up a NKA or NULL value.=20 --=20 Niall Litchfield Oracle DBA http://www.niall.litchfield.dial.pipex.com ------=_Part_4084_4946148.1123504049240 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Comments below
On 8/6/05, K= ennedy, Jim <jim_kennedy@m= entor.com> wrote:


I explain NULLS in the f= ollowing manner.

Imagine a medical application where your medical da= ta is stored in a
database.  Imagine that your Dr. has never asked you if you h= ave
allergies or not.  Further imagine that you become unconco= use and go to
the emergency room.  The Dr. in the emergency ro= om looks at your
electronic medical data.  Given the informati= on in your electronic chart
what should the Dr. assume about your allergic reactions?:
 &nb= sp;     A. You are Alergic to something.
  = ;     B. You are not allergic to anything.
 &nb= sp;     C. It is unknown if you are or are not allergic= to anything.

The Dr. should assume C.  You have not been asked the que= stion so the
data in that column is NULL and the Dr. should make NO assu= mptions about
your medical condition visa vis allergys.  In me= dicine even if they
asked you the question "Are you allergic to anything?" and yo= u answered
"No"  the correct value to store is NKA -= No Known Allergies.  After
this explanation most people under= stand what a NULL is.
Jim
 
Isn't this a great example of how a better design is a better solution= ?
Wouldn't
 
PATIENT
=3D=3D=3D=3D=3D=3D=3D
PATIENT_PK
....................
 
ALLERGEN
=3D=3D=3D=3D=3D=3D=3D=3D=3D
ALLERGEN_PK
........................
 
KNOWN_ALLERGIES
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
PATIENT_PK  -- foreign key
ALLERGEN_PK -- foreign key
IDENTIFIED_DATE
.....

 
Be a better design? Then the doctor would j= ust pull up a list of known allergies (which might of course be empty)= . This is a lot different, and I'd argue better, than pulling up a NKA= or NULL value.  

--
Niall Litchfield
Oracle DBA
http://www.niall.litchfield.dial.pipex.com= =20 ------=_Part_4084_4946148.1123504049240-- -- http://www.freelists.org/webpage/oracle-l