<div>Mark, what I beleive you are referring to is a Data Structure Diagram (see Figure 3-29 on page 109 of our Textbook) I am referring to Entity-Relationship Diagrams (see Figure 3-27 on page 107 of our Textbook). </div>
<div> </div>
<div>They appear to have a similar purpose, although they are quite different in appearance. <br><br></div>
<div class="gmail_quote">On Thu, Mar 31, 2011 at 8:22 AM, Mark KELLY <span dir="ltr"><<a href="mailto:kel@mckinnonsc.vic.edu.au">kel@mckinnonsc.vic.edu.au</a>></span> wrote:<br>
<blockquote style="BORDER-LEFT: #ccc 1px solid; MARGIN: 0px 0px 0px 0.8ex; PADDING-LEFT: 1ex" class="gmail_quote">Hi Peter<br>When I think of ERDs for databases, I'm seeing a picture of the database's tables with their related key fields connected by relationship lines. These lines usually have "1" on one end and a "many" symbol on the other... <br>
<br>Are we thinking of the same thing?<br><br>
<div class="gmail_quote">
<div>
<div></div>
<div class="h5">On 30 March 2011 16:54, Peter Langham <span dir="ltr"><<a href="mailto:peterlangham1983@gmail.com" target="_blank">peterlangham1983@gmail.com</a>></span> wrote:<br></div></div>
<blockquote style="BORDER-LEFT: #ccc 1px solid; MARGIN: 0px 0px 0px 0.8ex; PADDING-LEFT: 1ex" class="gmail_quote">
<div>
<div></div>
<div class="h5">
<div>Hi guys, </div>
<div> </div>
<div>I'm looking for some clarification on Entity-Relationship Diagrams. </div>
<div> </div>
<div>I'm planning to develop a pet shop database as that will have a Customers Table, Products Table and Orders Table.</div>
<div> </div>
<div>When I complete my entity-relationship diagram I will use Customers, Products and Orders (or Invoices) as my entities.</div>
<div> </div>
<div>But I'm unsure if I'm doing the Relationships correctly.</div>
<div> </div>
<div>Customer - BUYS - Product</div>
<div>Customer - PAYS - Order (or Invoice)</div>
<div>Order (or Invoice) - Displays/Outputs - Product (Information)</div>
<div> </div>
<div>Is this correct?</div>
<div> </div>
<div>Thanks for your time.</div>
<div> </div><font color="#888888">
<div>Peter Langham.</div>
<div>Narre Warren South P-12.</div></font><br></div></div>_<br clear="all"></blockquote></div><br>-- <br>Mark Kelly<br>Manager of ICT, Reporting, IT Learning Area<br>McKinnon Secondary College<br>McKinnon Rd McKinnon 3204, Victoria, Australia<br>
Direct line / Voicemail: <a href="tel:%2B613%208520%209085" target="_blank">+613 8520 9085</a>, Fax <a href="tel:%2B613%209578%209253" target="_blank">+613 9578 9253</a><br><a href="mailto:kel@mckinnonsc.vic.edu.au" target="_blank">kel@mckinnonsc.vic.edu.au</a><br>
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