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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Towards the end of each cycle of the accreditation period there
is an opportunity to provide comments and suggested alterations to the study
design. Perhaps the VCAA and/or VITTA could publicise this opportunity so that
people can nominate to be on the committee, or a process can be set up whereby
comments are fed through to a representative to present to the committee .<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Having been on the committee myself once in the past, I found it
very useful, especially in terms of discussing what should be covered in the
course with people from industry, TAFE and University to get their perspective
on what needs to be covered. And the VCAA did listen to our concerns and did
incorporate many of our suggestions into the previous study design.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'> <o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'>Kind regards</span><span style='color:#1F497D'><o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'> <o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'>Allan Barnes, CEO</span><span style='color:#1F497D'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'>Australian Institute of Education and Training</span><span
style='color:#1F497D'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'>P.O. Box 171</span><span style='color:#1F497D'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'>Brunswick West 3055</span><span style='color:#1F497D'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'>Ph: (03) 9387 2051</span><span style='color:#1F497D'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'>FAX: (03) 9387 3470</span><span style='color:#1F497D'><o:p></o:p></span></p>
</div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'>Mobile: 0409 428 221<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
sofdev-bounces@edulists.com.au [mailto:sofdev-bounces@edulists.com.au] <b>On
Behalf Of </b>Andrew Shortell<br>
<b>Sent:</b> Thursday, 16 October 2008 9:23 AM<br>
<b>To:</b> Year 12 Software Development Teachers' Mailing List<br>
<b>Subject:</b> RE: [Year 12 SofDev] RE: Database question and confusion<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span lang=EN-AU style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>A better question would be <o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-AU style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>“Why are they so vague?”<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-AU style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>And then<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-AU style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>“What is the purpose of the lack of precision in a subject that
is mostly about being precise?”<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-AU style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-AU style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>The answers to those questions would illuminate many of the
areas of confusion……. <o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-AU style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>So talk to people who were on the panel of the current study
design<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-AU style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<div>
<p class=MsoNormal><span lang=EN-AU style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Andrew Shortell<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-AU style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Braemar College<o:p></o:p></span></p>
</div>
<p class=MsoNormal><span lang=EN-AU style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
sofdev-bounces@edulists.com.au [mailto:sofdev-bounces@edulists.com.au] <b>On
Behalf Of </b>Russell Quinn<br>
<b>Sent:</b> Wednesday, 15 October 2008 3:10 PM<br>
<b>To:</b> sofdev@edulists.com.au<br>
<b>Subject:</b> [Year 12 SofDev] RE: Database question and confusion<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><span lang=EN-AU><o:p> </o:p></span></p>
<div id=idOWAReplyText36118>
<div>
<p class=MsoNormal><span lang=EN-AU style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:black'>Another excellent reason for having a properly</span><span
lang=EN-AU><o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span lang=EN-AU style='font-size:10.0pt;font-family:"Arial","sans-serif"'>defined
course. Our current VCAA statements</span><span lang=EN-AU><o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span lang=EN-AU style='font-size:10.0pt;font-family:"Arial","sans-serif"'>only
breed confusion and inefficiency. They wast</span><span lang=EN-AU><o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span lang=EN-AU style='font-size:10.0pt;font-family:"Arial","sans-serif"'>out
time and there students time, esp. when there</span><span lang=EN-AU><o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span lang=EN-AU style='font-size:10.0pt;font-family:"Arial","sans-serif"'>is
precious little time to spare. But no</span><span lang=EN-AU><o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span lang=EN-AU style='font-size:10.0pt;font-family:"Arial","sans-serif"'>one
ever seems to listen or respond.</span><span lang=EN-AU><o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span lang=EN-AU> <o:p></o:p></span></p>
</div>
</div>
<div id=idSignature40901>
<div>
<p class=MsoNormal><span lang=EN-AU style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:black'>Russell Quinn</span><span lang=EN-AU><o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span lang=EN-AU> <o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span lang=EN-AU style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Mailto:
<a href="mailto:qn@boxhillhs.vic.edu.au" target="_blank">qn@boxhillhs.vic.edu.au</a></span><span
lang=EN-AU><o:p></o:p></span></p>
</div>
</div>
<div>
<p class=MsoNormal><span lang=EN-AU><o:p> </o:p></span></p>
<div class=MsoNormal align=center style='text-align:center'><span lang=EN-AU>
<hr size=2 width="100%" align=center>
</span></div>
<p class=MsoNormal style='margin-bottom:12.0pt'><b><span lang=EN-AU
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
lang=EN-AU style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
sofdev-request@edulists.com.au<br>
<b>Sent:</b> Tue 14/10/2008 1:00 PM<br>
<b>To:</b> sofdev@edulists.com.au<br>
<b>Subject:</b> sofdev Digest, Vol 44, Issue 4</span><span lang=EN-AU><o:p></o:p></span></p>
</div>
<div><pre style='WORD-WRAP: break-word'><span lang=EN-AU>Send sofdev mailing list submissions to<o:p></o:p></span></pre><pre><span
lang=EN-AU> sofdev@edulists.com.au<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>To subscribe or unsubscribe via the World Wide Web, visit<o:p></o:p></span></pre><pre><span
lang=EN-AU> http://www.edulists.com.au/mailman/listinfo/sofdev<o:p></o:p></span></pre><pre><span
lang=EN-AU>or, via email, send a message with subject or body 'help' to<o:p></o:p></span></pre><pre><span
lang=EN-AU> sofdev-request@edulists.com.au<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>You can reach the person managing the list at<o:p></o:p></span></pre><pre><span
lang=EN-AU> sofdev-owner@edulists.com.au<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>When replying, please edit your Subject line so it is more specific<o:p></o:p></span></pre><pre><span
lang=EN-AU>than "Re: Contents of sofdev digest..."<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU>Today's Topics:<o:p></o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU> 1. RE: Database question (Quentin Lydall)<o:p></o:p></span></pre><pre><span
lang=EN-AU> 2. Re: Database question (Mark Kelly)<o:p></o:p></span></pre><pre><span
lang=EN-AU> 3. Re: Special thanks to Associate Professor Steven Bird<o:p></o:p></span></pre><pre><span
lang=EN-AU> (Kevork Krozian)<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU>----------------------------------------------------------------------<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>Message: 1<o:p></o:p></span></pre><pre><span
lang=EN-AU>Date: Tue, 14 Oct 2008 12:10:07 +1100<o:p></o:p></span></pre><pre><span
lang=EN-AU>From: "Quentin Lydall" <qly@beaconhills.vic.edu.au><o:p></o:p></span></pre><pre><span
lang=EN-AU>Subject: RE: [Year 12 SofDev] Database question<o:p></o:p></span></pre><pre><span
lang=EN-AU>To: "Year 12 Software Development Teachers' Mailing List"<o:p></o:p></span></pre><pre><span
lang=EN-AU> <sofdev@edulists.com.au><o:p></o:p></span></pre><pre><span
lang=EN-AU>Message-ID:<o:p></o:p></span></pre><pre><span lang=EN-AU> <AFC3563D81D1044097735D5F6A3DBBE5014D7B6E@valley02.Beaconhills.beaconhills.vic.edu.au><o:p></o:p></span></pre><pre><span
lang=EN-AU> <o:p></o:p></span></pre><pre><span
lang=EN-AU>Content-Type: text/plain; charset="UTF-8"<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>I agree. Students should understand normalization, primary and foreign keys, lookup tables, data types and their properties, etc. There just is a fundamental logic error in the formulation of this answer, in a database context. Maybe it was done late at night..<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>Quentin Lydall<o:p></o:p></span></pre><pre><span
lang=EN-AU>Head of ICT<o:p></o:p></span></pre><pre><span lang=EN-AU>Beaconhills College Valley Campus<o:p></o:p></span></pre><pre><span
lang=EN-AU>30-34 Toomuc Valley Road,<o:p></o:p></span></pre><pre><span
lang=EN-AU>Pakenham<o:p></o:p></span></pre><pre><span lang=EN-AU>3810<o:p></o:p></span></pre><pre><span
lang=EN-AU>Phone: 1300 002 225 Extn 3016<o:p></o:p></span></pre><pre><span
lang=EN-AU> Please consider the environment before printing my email</span><span
lang=EN-AU style='font-family:Symbol'>P</span><span lang=EN-AU><o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>-----Original Message-----<o:p></o:p></span></pre><pre><span
lang=EN-AU>From: sofdev-bounces@edulists.com.au [mailto:sofdev-bounces@edulists.com.au] On Behalf Of Steven Bird<o:p></o:p></span></pre><pre><span
lang=EN-AU>Sent: Tuesday, 14 October 2008 11:58 AM<o:p></o:p></span></pre><pre><span
lang=EN-AU>To: Year 12 Software Development Teachers' Mailing List<o:p></o:p></span></pre><pre><span
lang=EN-AU>Subject: Re: [Year 12 SofDev] Database question<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>On Tue, Oct 14, 2008 at 11:13 AM, Adrian Janson<o:p></o:p></span></pre><pre><span
lang=EN-AU><janson.adrian.a@edumail.vic.gov.au> wrote:<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Yes – quite correct. My students spotted this as well. The x5 is not<o:p></o:p></span></pre><pre><span
lang=EN-AU>> required.<o:p></o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU>There's some other problems though. A database with 20,000 customers<o:p></o:p></span></pre><pre><span
lang=EN-AU>should have one or more indexes to support efficient retrieval, and<o:p></o:p></span></pre><pre><span
lang=EN-AU>these take space. Nightly dumps take space as well. If the question<o:p></o:p></span></pre><pre><span
lang=EN-AU>is getting at how much disk space we should budget for, these factors<o:p></o:p></span></pre><pre><span
lang=EN-AU>are relevant.<o:p></o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU>It would be bad database design to store postcode and suburb with each<o:p></o:p></span></pre><pre><span
lang=EN-AU>customer record (cf [1]). Instead a customer record should contain a<o:p></o:p></span></pre><pre><span
lang=EN-AU>foreign key to a table of postcodes, e.g. a subset of [2]. We're told<o:p></o:p></span></pre><pre><span
lang=EN-AU>the company only has sales in a "local area", so perhaps we'd only<o:p></o:p></span></pre><pre><span
lang=EN-AU>have to deal with a dozen postcodes. That table would be a constant<o:p></o:p></span></pre><pre><span
lang=EN-AU>size overhead which is easy to compute, and the foreign key would be a<o:p></o:p></span></pre><pre><span
lang=EN-AU>short integer (e.g. TINYINT).<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>The question treats a database as if it was a spreadsheet, and only<o:p></o:p></span></pre><pre><span
lang=EN-AU>requires students to know the relative sizes of characters, bytes, and<o:p></o:p></span></pre><pre><span
lang=EN-AU>bits.<o:p></o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU>It would be good if students learnt about normalization and the<o:p></o:p></span></pre><pre><span
lang=EN-AU>importance of avoiding duplication in a database. It would also be<o:p></o:p></span></pre><pre><span
lang=EN-AU>nice if they learnt what Unicode is, and that 1 character != 1 byte.<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>[1] http://en.wikipedia.org/wiki/Database_normalization<o:p></o:p></span></pre><pre><span
lang=EN-AU>[2] http://www1.auspost.com.au/download/pc-full.zip<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>-Steven Bird<o:p></o:p></span></pre><pre><span
lang=EN-AU>http://www.csse.unimelb.edu.au/~sb/<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>> A database for an online marketing company keeps records of all customers<o:p></o:p></span></pre><pre><span
lang=EN-AU>> who have requested coupons and notifications of sales in their local area.<o:p></o:p></span></pre><pre><span
lang=EN-AU>> They currently have a dedicated customer base of around 5000 customers, but<o:p></o:p></span></pre><pre><span
lang=EN-AU>> wish to grow this to 20,000 customers within the next 5 years. How much<o:p></o:p></span></pre><pre><span
lang=EN-AU>> storage capacity will be required to store 20,000 customer records for the<o:p></o:p></span></pre><pre><span
lang=EN-AU>> entire 5 year period, given the following information:<o:p></o:p></span></pre><pre><span
lang=EN-AU>> First Name – 50 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Last Name – 50 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Address – 100 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Suburb – 50 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Phone number – 10 characters each (2 phone numbers per customer)<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Email address – 50 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Postcode – 4 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Number of coupons received – 32-bit number<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>><o:p> </o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> A. 34,200,000 bytes<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> B. 32,400,000 bytes<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> C. 35,600,000 bytes<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> D. 32,800,000 bytes<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>><o:p> </o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> The solution gives D with the explanation<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> 50+50+100+50+10+10+50+4+4 =<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> 328<o:p></o:p></span></pre><pre><span
lang=EN-AU>> 328 x 20000 x 5 = 32,800,000<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> Why multiply by 5? Would the company recreate the entire records each<o:p></o:p></span></pre><pre><span
lang=EN-AU>> year? I'd design it differently..<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>><o:p> </o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> Appreciate your help.<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>><o:p> </o:p></span></pre><pre><span
lang=EN-AU>> Quentin Lydall<o:p></o:p></span></pre><pre><span lang=EN-AU>> Head of ICT<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Beaconhills College Valley Campus<o:p></o:p></span></pre><pre><span
lang=EN-AU>> 30-34 Toomuc Valley Road,<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Pakenham<o:p></o:p></span></pre><pre><span lang=EN-AU>> 3810<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Phone: 1300 002 225 Extn 3016<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> P Please consider the environment before printing my email<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU>#####################################################################################<o:p></o:p></span></pre><pre><span
lang=EN-AU>This email is confidential and intended solely for the use of the individual to whom <o:p></o:p></span></pre><pre><span
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lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>------------------------------<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>Message: 2<o:p></o:p></span></pre><pre><span
lang=EN-AU>Date: Tue, 14 Oct 2008 12:51:48 +1100<o:p></o:p></span></pre><pre><span
lang=EN-AU>From: Mark Kelly <kel@mckinnonsc.vic.edu.au><o:p></o:p></span></pre><pre><span
lang=EN-AU>Subject: Re: [Year 12 SofDev] Database question<o:p></o:p></span></pre><pre><span
lang=EN-AU>To: "Year 12 Software Development Teachers' Mailing List"<o:p></o:p></span></pre><pre><span
lang=EN-AU> <sofdev@edulists.com.au><o:p></o:p></span></pre><pre><span
lang=EN-AU>Message-ID: <48F3FB34.3010003@mckinnonsc.vic.edu.au><o:p></o:p></span></pre><pre><span
lang=EN-AU>Content-Type: text/plain; charset=windows-1252; format=flowed<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>I see what you mean, but I think the question writer just used a <o:p></o:p></span></pre><pre><span
lang=EN-AU>database as a vehicle for interrogating students' knowledge of number <o:p></o:p></span></pre><pre><span
lang=EN-AU>types.<o:p></o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU>Since database structure is not part of the study design, a question <o:p></o:p></span></pre><pre><span
lang=EN-AU>that required knowledge of indexes, normalisation, and relational links <o:p></o:p></span></pre><pre><span
lang=EN-AU>etc could not, IMO, be justified.<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>2 cents worth (and devaluing rapidly). Only a year without teaching SD <o:p></o:p></span></pre><pre><span
lang=EN-AU>and my memory of it is getting rusty already!<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>Cheers<o:p></o:p></span></pre><pre><span
lang=EN-AU>Mark<o:p></o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU>Steven Bird wrote:<o:p></o:p></span></pre><pre><span lang=EN-AU>> On Tue, Oct 14, 2008 at 11:13 AM, Adrian Janson<o:p></o:p></span></pre><pre><span
lang=EN-AU>> <janson.adrian.a@edumail.vic.gov.au> wrote:<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> Yes quite correct. My students spotted this as well. The x5 is not<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> required.<o:p></o:p></span></pre><pre><span lang=EN-AU>> <o:p></o:p></span></pre><pre><span
lang=EN-AU>> There's some other problems though. A database with 20,000 customers<o:p></o:p></span></pre><pre><span
lang=EN-AU>> should have one or more indexes to support efficient retrieval, and<o:p></o:p></span></pre><pre><span
lang=EN-AU>> these take space. Nightly dumps take space as well. If the question<o:p></o:p></span></pre><pre><span
lang=EN-AU>> is getting at how much disk space we should budget for, these factors<o:p></o:p></span></pre><pre><span
lang=EN-AU>> are relevant.<o:p></o:p></span></pre><pre><span lang=EN-AU>> <o:p></o:p></span></pre><pre><span
lang=EN-AU>> It would be bad database design to store postcode and suburb with each<o:p></o:p></span></pre><pre><span
lang=EN-AU>> customer record (cf [1]). Instead a customer record should contain a<o:p></o:p></span></pre><pre><span
lang=EN-AU>> foreign key to a table of postcodes, e.g. a subset of [2]. We're told<o:p></o:p></span></pre><pre><span
lang=EN-AU>> the company only has sales in a "local area", so perhaps we'd only<o:p></o:p></span></pre><pre><span
lang=EN-AU>> have to deal with a dozen postcodes. That table would be a constant<o:p></o:p></span></pre><pre><span
lang=EN-AU>> size overhead which is easy to compute, and the foreign key would be a<o:p></o:p></span></pre><pre><span
lang=EN-AU>> short integer (e.g. TINYINT).<o:p></o:p></span></pre><pre><span
lang=EN-AU>> <o:p></o:p></span></pre><pre><span lang=EN-AU>> The question treats a database as if it was a spreadsheet, and only<o:p></o:p></span></pre><pre><span
lang=EN-AU>> requires students to know the relative sizes of characters, bytes, and<o:p></o:p></span></pre><pre><span
lang=EN-AU>> bits.<o:p></o:p></span></pre><pre><span lang=EN-AU>> <o:p></o:p></span></pre><pre><span
lang=EN-AU>> It would be good if students learnt about normalization and the<o:p></o:p></span></pre><pre><span
lang=EN-AU>> importance of avoiding duplication in a database. It would also be<o:p></o:p></span></pre><pre><span
lang=EN-AU>> nice if they learnt what Unicode is, and that 1 character != 1 byte.<o:p></o:p></span></pre><pre><span
lang=EN-AU>> <o:p></o:p></span></pre><pre><span lang=EN-AU>> [1] http://en.wikipedia.org/wiki/Database_normalization<o:p></o:p></span></pre><pre><span
lang=EN-AU>> [2] http://www1.auspost.com.au/download/pc-full.zip<o:p></o:p></span></pre><pre><span
lang=EN-AU>> <o:p></o:p></span></pre><pre><span lang=EN-AU>> -Steven Bird<o:p></o:p></span></pre><pre><span
lang=EN-AU>> http://www.csse.unimelb.edu.au/~sb/<o:p></o:p></span></pre><pre><span
lang=EN-AU>> <o:p></o:p></span></pre><pre><span lang=EN-AU>>> A database for an online marketing company keeps records of all customers<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> who have requested coupons and notifications of sales in their local area.<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> They currently have a dedicated customer base of around 5000 customers, but<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> wish to grow this to 20,000 customers within the next 5 years. How much<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> storage capacity will be required to store 20,000 customer records for the<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> entire 5 year period, given the following information:<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> First Name 50 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> Last Name 50 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> Address 100 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> Suburb 50 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> Phone number 10 characters each (2 phone numbers per customer)<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> Email address 50 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> Postcode 4 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> Number of coupons received 32-bit number<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>><o:p> </o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> A. 34,200,000 bytes<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> B. 32,400,000 bytes<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> C. 35,600,000 bytes<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> D. 32,800,000 bytes<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>><o:p> </o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> The solution gives D with the explanation<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> 50+50+100+50+10+10+50+4+4 =<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> 328<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> 328 x 20000 x 5 = 32,800,000<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> Why multiply by 5? Would the company recreate the entire records each<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> year? I'd design it differently..<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>><o:p> </o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> Appreciate your help.<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>><o:p> </o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>><o:p> </o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> Quentin Lydall<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> Head of ICT<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> Beaconhills College Valley Campus<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> 30-34 Toomuc Valley Road,<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> Pakenham<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> 3810<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> Phone: 1300 002 225 Extn 3016<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> P Please consider the environment before printing my email<o:p></o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>><o:p> </o:p></span></pre><pre><span
lang=EN-AU>>><o:p> </o:p></span></pre><pre><span lang=EN-AU>>> ________________________________<o:p></o:p></span></pre><pre><span
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lang=EN-AU>>> individual to whom it is addressed. Any views or opinions presented are<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> solely those of the author and do not necessarily represent those of<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> Beaconhills College. If you are not the intended recipient, be advised that<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> you have received this email in error and that any use, dissemination,<o:p></o:p></span></pre><pre><span
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lang=EN-AU>>> supported by<o:p></o:p></span></pre><pre><span lang=EN-AU>>> http://www.vitta.org.au/vce/studies/infotech/softwaredevel3-4.html -<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> Victorian Curriculum and Assessment Authority and<o:p></o:p></span></pre><pre><span
lang=EN-AU>>> http://www.vitta.org.au - VITTA Victorian Information Technology Teachers<o:p></o:p></span></pre><pre><span
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lang=EN-AU>> IT Software Development Mailing List kindly supported by<o:p></o:p></span></pre><pre><span
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lang=EN-AU>> http://www.vitta.org.au/vce/studies/infotech/softwaredevel3-4.html - VITTA Victorian Information Technology Teachers Association Inc<o:p></o:p></span></pre><pre><span
lang=EN-AU>> <o:p></o:p></span></pre><pre><span lang=EN-AU>> <o:p></o:p></span></pre><pre><span
lang=EN-AU>> <o:p></o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>-- <o:p></o:p></span></pre><pre><span
lang=EN-AU>Mark Kelly<o:p></o:p></span></pre><pre><span lang=EN-AU>Manager - Information Systems<o:p></o:p></span></pre><pre><span
lang=EN-AU>McKinnon Secondary College<o:p></o:p></span></pre><pre><span
lang=EN-AU>McKinnon Rd McKinnon 3204, Victoria, Australia<o:p></o:p></span></pre><pre><span
lang=EN-AU>Direct line / Voicemail: 8520 9085<o:p></o:p></span></pre><pre><span
lang=EN-AU>School Phone +613 8520 9000<o:p></o:p></span></pre><pre><span
lang=EN-AU>School Fax +613 95789253<o:p></o:p></span></pre><pre><span
lang=EN-AU>kel AT mckinnonsc.vic.edu.au<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>Webmaster - http://www.mckinnonsc.vic.edu.au<o:p></o:p></span></pre><pre><span
lang=EN-AU>IT Lecture notes: http://vceit.com<o:p></o:p></span></pre><pre><span
lang=EN-AU>Moderator: IT Applications Mailing List<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>A conclusion is the place where you got sick of thinking.<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>------------------------------<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>Message: 3<o:p></o:p></span></pre><pre><span
lang=EN-AU>Date: Tue, 14 Oct 2008 11:58:39 +1100<o:p></o:p></span></pre><pre><span
lang=EN-AU>From: "Kevork Krozian" <Kroset@novell1.fhc.vic.edu.au><o:p></o:p></span></pre><pre><span
lang=EN-AU>Subject: Re: [Year 12 SofDev] Special thanks to Associate Professor<o:p></o:p></span></pre><pre><span
lang=EN-AU> Steven Bird<o:p></o:p></span></pre><pre><span
lang=EN-AU>To: "Year 12 Software Development Teachers' Mailing List"<o:p></o:p></span></pre><pre><span
lang=EN-AU> <sofdev@edulists.com.au><o:p></o:p></span></pre><pre><span
lang=EN-AU>Message-ID: <48F497EE.EE3E.0095.0@novell1.fhc.vic.edu.au><o:p></o:p></span></pre><pre><span
lang=EN-AU>Content-Type: text/plain; charset=ISO-8859-15<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>Hi Steven,<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU> I think we are very fortunate and privileged to have your time and<o:p></o:p></span></pre><pre><span
lang=EN-AU>expertise on these lists. <o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>I am sure you have other pressing demands on your time not least of<o:p></o:p></span></pre><pre><span
lang=EN-AU>which in your lecturing and related duties in the Uni of Melbourne<o:p></o:p></span></pre><pre><span
lang=EN-AU>Computer Science faculty and other projects, research and activities you<o:p></o:p></span></pre><pre><span
lang=EN-AU>are working on as recorded on http://www.csse.unimelb.edu.au/~sb/ .<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>Your explanations and insights into implications of certain questions<o:p></o:p></span></pre><pre><span
lang=EN-AU>on both the final and practice exams in Software Development can only<o:p></o:p></span></pre><pre><span
lang=EN-AU>help us all to become better teachers if for no other reason than the<o:p></o:p></span></pre><pre><span
lang=EN-AU>seed it plants to think about problems from another perspective and<o:p></o:p></span></pre><pre><span
lang=EN-AU>hopefully continue the discussion and seek further clarification.<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU> So on behalf of the list membership, please keep your comments coming<o:p></o:p></span></pre><pre><span
lang=EN-AU>and thanks for your time.<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU>Best Wishes<o:p></o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>Kevork Krozian<o:p></o:p></span></pre><pre><span
lang=EN-AU>IT Manager , Forest Hill College<o:p></o:p></span></pre><pre><span
lang=EN-AU>k.krozian@fhc.vic.edu.au<o:p></o:p></span></pre><pre><span
lang=EN-AU>http://www.fhc.vic.edu.au<o:p></o:p></span></pre><pre><span
lang=EN-AU>Mobile: 0419 356 034<o:p></o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU>>>> "Steven Bird" <sb@csse.unimelb.edu.au> 14/10/2008 11:57 am >>><o:p></o:p></span></pre><pre><span
lang=EN-AU>On Tue, Oct 14, 2008 at 11:13 AM, Adrian Janson<o:p></o:p></span></pre><pre><span
lang=EN-AU><janson.adrian.a@edumail.vic.gov.au> wrote:<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Yes * quite correct. My students spotted this as well. The x5 is<o:p></o:p></span></pre><pre><span
lang=EN-AU>not<o:p></o:p></span></pre><pre><span lang=EN-AU>> required.<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>There's some other problems though. A database with 20,000 customers<o:p></o:p></span></pre><pre><span
lang=EN-AU>should have one or more indexes to support efficient retrieval, and<o:p></o:p></span></pre><pre><span
lang=EN-AU>these take space. Nightly dumps take space as well. If the question<o:p></o:p></span></pre><pre><span
lang=EN-AU>is getting at how much disk space we should budget for, these factors<o:p></o:p></span></pre><pre><span
lang=EN-AU>are relevant.<o:p></o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU>It would be bad database design to store postcode and suburb with each<o:p></o:p></span></pre><pre><span
lang=EN-AU>customer record (cf [1]). Instead a customer record should contain a<o:p></o:p></span></pre><pre><span
lang=EN-AU>foreign key to a table of postcodes, e.g. a subset of [2]. We're told<o:p></o:p></span></pre><pre><span
lang=EN-AU>the company only has sales in a "local area", so perhaps we'd only<o:p></o:p></span></pre><pre><span
lang=EN-AU>have to deal with a dozen postcodes. That table would be a constant<o:p></o:p></span></pre><pre><span
lang=EN-AU>size overhead which is easy to compute, and the foreign key would be a<o:p></o:p></span></pre><pre><span
lang=EN-AU>short integer (e.g. TINYINT).<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>The question treats a database as if it was a spreadsheet, and only<o:p></o:p></span></pre><pre><span
lang=EN-AU>requires students to know the relative sizes of characters, bytes, and<o:p></o:p></span></pre><pre><span
lang=EN-AU>bits.<o:p></o:p></span></pre><pre><span lang=EN-AU><o:p> </o:p></span></pre><pre><span
lang=EN-AU>It would be good if students learnt about normalization and the<o:p></o:p></span></pre><pre><span
lang=EN-AU>importance of avoiding duplication in a database. It would also be<o:p></o:p></span></pre><pre><span
lang=EN-AU>nice if they learnt what Unicode is, and that 1 character != 1 byte.<o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>[1] http://en.wikipedia.org/wiki/Database_normalization <o:p></o:p></span></pre><pre><span
lang=EN-AU>[2] http://www1.auspost.com.au/download/pc-full.zip <o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>-Steven Bird<o:p></o:p></span></pre><pre><span
lang=EN-AU>http://www.csse.unimelb.edu.au/~sb/ <o:p></o:p></span></pre><pre><span
lang=EN-AU><o:p> </o:p></span></pre><pre><span lang=EN-AU>> A database for an online marketing company keeps records of all<o:p></o:p></span></pre><pre><span
lang=EN-AU>customers<o:p></o:p></span></pre><pre><span lang=EN-AU>> who have requested coupons and notifications of sales in their local<o:p></o:p></span></pre><pre><span
lang=EN-AU>area.<o:p></o:p></span></pre><pre><span lang=EN-AU>> They currently have a dedicated customer base of around 5000<o:p></o:p></span></pre><pre><span
lang=EN-AU>customers, but<o:p></o:p></span></pre><pre><span lang=EN-AU>> wish to grow this to 20,000 customers within the next 5 years. How<o:p></o:p></span></pre><pre><span
lang=EN-AU>much<o:p></o:p></span></pre><pre><span lang=EN-AU>> storage capacity will be required to store 20,000 customer records<o:p></o:p></span></pre><pre><span
lang=EN-AU>for the<o:p></o:p></span></pre><pre><span lang=EN-AU>> entire 5 year period, given the following information:<o:p></o:p></span></pre><pre><span
lang=EN-AU>> First Name * 50 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Last Name * 50 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Address * 100 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Suburb * 50 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Phone number * 10 characters each (2 phone numbers per customer)<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Email address * 50 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Postcode * 4 characters<o:p></o:p></span></pre><pre><span
lang=EN-AU>> Number of coupons received * 32-bit number<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>><o:p> </o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> A. 34,200,000 bytes<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> B. 32,400,000 bytes<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> C. 35,600,000 bytes<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> D. 32,800,000 bytes<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>><o:p> </o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> The solution gives D with the explanation<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> 50+50+100+50+10+10+50+4+4 =<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> 328<o:p></o:p></span></pre><pre><span
lang=EN-AU>> 328 x 20000 x 5 = 32,800,000<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>> Why multiply by 5? Would the company recreate the entire records<o:p></o:p></span></pre><pre><span
lang=EN-AU>each<o:p></o:p></span></pre><pre><span lang=EN-AU>> year? I'd design it differently..<o:p></o:p></span></pre><pre><span
lang=EN-AU>><o:p> </o:p></span></pre><pre><span lang=EN-AU>><o:p> </o:p></span></pre><pre><span
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lang=EN-AU>End of sofdev Digest, Vol 44, Issue 4<o:p></o:p></span></pre><pre><span
lang=EN-AU>*************************************<o:p></o:p></span></pre></div>
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