dali/docs/3.2/user_guide/concept_mapping.htm - gerrit/www.eclipse.org/webtools - Git at Google

 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
     "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
 <head>
 <meta http-equiv="Content-Type" content="text/html; charset=us-ascii" />
 <meta http-equiv="Content-Style-Type" content="text/css" />
 <meta http-equiv="Content-Script-Type" content="text/javascript" />
 <title>Understanding OR mappings</title>
 <meta name="generator" content="Oracle DARB XHTML Converter (Mode = document) - Version 1.0.11" />
 <meta name="date" content="2012-12-19T9:17:39Z" />
 <meta name="robots" content="noarchive" />
 <meta name="doctitle" content="Understanding OR mappings" />
 <meta name="relnum" content="Release 3.2" />
 <meta name="partnum" content="Release 3.2" />
 <link rel="copyright" href="dcommon/html/cpyr.htm" title="Copyright" type="text/html" />
 <link rel="stylesheet" href="dcommon/css/blafdoc.css" title="Oracle BLAFDoc" type="text/css" />
 <link rel="contents" href="toc.htm" title="Contents" type="text/html" />
 <link rel="up" href="../../index.htm" title="Home" type="text/html" />
 <link rel="up" href="toc.htm" title="User Guide" type="text/html" />
 <link rel="up" href="concepts.htm" title="Concepts" type="text/html" />
 <link rel="up" href="concept_mapping.htm" title="Understanding OR mappings" type="text/html" />
 <link rel="index" href="index.htm" title="Index" type="text/html" />
 <link rel="prev" href="concept_persistence.htm" title="Understanding Java persistence " type="text/html" />
 <link rel="next" href="concepts001.htm" title="Understanding Java Persistence API" type="text/html" />
 </head>
 <body>
 <div class="header"><a id="top" name="top"></a>
 <div class="zz-skip-header"><a href="#BEGIN">Skip Headers</a></div>
 <table class="simple oac_no_warn" summary="" cellspacing="0" cellpadding="0" width="100%">
 <tr>
 <td align="left" valign="top"><b>Dali Java Persistence Tools User Guide</b><br />
 <b>Release 3.2</b><br />
 Release 3.2</td>
 <td valign="bottom" align="right">
 <table class="simple oac_no_warn" summary="" cellspacing="0" cellpadding="0" width="225">
 <tr>
 <td>&nbsp;</td>
 <td align="center" valign="top"><a href="../dali_user_guide.pdf"><img src="dcommon/gifs/pdf_icon.png" alt="PDF" height="24" /><br /><span class="icon">PDF</span></a></td><td align="center" valign="top"><a href="toc.htm"><img src="dcommon/gifs/toc.gif" alt="Go To Table Of Contents" /><br />
 <span class="icon">Contents</span></a></td>
 <td align="center" valign="top"><a href="index.htm"><img src="dcommon/gifs/index.gif" alt="Go To Index" /><br />
 <span class="icon">Index</span></a></td>
 </tr>
 </table>
 </td>
 </tr>
 </table>
 <hr />
 <table class="simple oac_no_warn" summary="" cellspacing="0" cellpadding="0" width="100">
 <tr>
 <td align="center"><a href="concept_persistence.htm"><img src="dcommon/gifs/leftnav.gif" alt="Previous" /><br />
 <span class="icon">Understanding Java persistence</span></a> &nbsp;</td>
 <td align="center"><a href="concepts001.htm"><img src="dcommon/gifs/rightnav.gif" alt="Next" /><br />
 <span class="icon">Understanding Java Persistence API</span></a></td>
 <td>&nbsp;</td>
 </tr>
 </table>
 <p id="BREADCRUMBING"><a href="../../index.htm" title="Home">Home</a> &gt; <a href="toc.htm" title="User Guide">User Guide</a> &gt; <a href="concepts.htm" title="Concepts">Concepts</a> &gt; Understanding OR mappings</p>
 <a name="BEGIN" id="BEGIN"></a></div>
 <!-- class="header" -->
 <div class="ind"><!-- End Header --><a id="BABBDJFI" name="BABBDJFI"></a>
 <div class="sect1">
 <h1 class="sect1">Understanding OR mappings</h1>
 <p><a id="sthref22" name="sthref22"></a><a id="sthref23" name="sthref23"></a>The Dali OR (object-relational) Mapping Tool allows you to describe how your entity objects <span class="italic">map</span> to the data source (or other objects). This approach isolates persistence information from the object model&ndash;developers are free to design their ideal object model, and DBAs are free to design their ideal schema.</p>
 <p>These mappings transform an object data member type to a corresponding relational database data source representation. These OR mappings can also transform object data members that reference other domain objects stored in other tables in the database and are related through foreign keys.</p>
 <p>You can use these mappings to map simple data types including primitives (such as <code>int</code>), JDK classes (such as <code>String</code>), and large object (LOB) values. You can also use them to transform object data members that reference other domain objects by way of association where data source representations require object identity maintenance (such as sequencing and back references) and possess various types of multiplicity and navigability. The appropriate mapping class is chosen primarily by the cardinality of the relationship.</p>
 <a id="sthref24" name="sthref24"></a>
 <p class="subhead2">Related tasks</p>
 <ul>
 <li>
 <p><a href="task_mapping.htm#BABDGBIJ">Mapping an entity</a></p>
 </li>
 </ul>
 </div>
 <!-- class="sect1" --></div>
 <!-- class="ind" -->
 <!-- Start Footer -->
 <div class="footer">
 <hr />
 <table class="simple oac_no_warn" summary="" cellspacing="0" cellpadding="0" width="100%">
 <col width="33%" />
 <col width="*" />
 <col width="33%" />
 <tr>
 <td valign="bottom">
 <table class="simple oac_no_warn" summary="" cellspacing="0" cellpadding="0" width="100">
 <col width="*" />
 <col width="48%" />
 <col width="48%" />
 <tr>
 <td>&nbsp;</td>
 <td align="center"><a href="concept_persistence.htm"><img src="dcommon/gifs/leftnav.gif" alt="Previous" /><br />
 <span class="icon">Understanding Java persistence</span></a> &nbsp;</td>
 <td align="center"><a href="concepts001.htm"><img src="dcommon/gifs/rightnav.gif" alt="Next" /><br />
 <span class="icon">Understanding Java Persistence API</span></a></td>
 </tr>
 </table>
 </td>
 <td class="copyrightlogo"><img class="copyrightlogo" src="http://www.eclipse.org/eclipse.org-common/themes/Nova/images/eclipse.png" alt="Eclipse Logo" width="150"/><br />
 <span class="copyrightlogo">Copyright&nbsp;&copy;&nbsp;2011, 2012,&nbspby The Eclipse Foundation under the Eclipse Public License (EPL).</span> <a href="legal.htm"><br />
 <span class="copyrightlogo">Legal Notices</span></a></td>
 <td valign="bottom" align="right">
 <table class="simple oac_no_warn" summary="" cellspacing="0" cellpadding="0" width="225">
 <tr>
 <td>&nbsp;</td>
 <td align="center" valign="top"><a href="../dali_user_guide.pdf"><img src="dcommon/gifs/pdf_icon.png" alt="PDF" height="24" /><br /><span class="icon">PDF</span></a></td><td align="center" valign="top"><a href="toc.htm"><img src="dcommon/gifs/toc.gif" alt="Go To Table Of Contents" /><br />
 <span class="icon">Contents</span></a></td>
 <td align="center" valign="top"><a href="index.htm"><img src="dcommon/gifs/index.gif" alt="Go To Index" /><br />
 <span class="icon">Index</span></a></td>
 </tr>
 </table>
 </td>
 </tr>
 </table>
 </div>
 <!-- class="footer" -->
 </body>
 </html>
	<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
	"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
	<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
	<head>
	<meta http-equiv="Content-Type" content="text/html; charset=us-ascii" />
	<meta http-equiv="Content-Style-Type" content="text/css" />
	<meta http-equiv="Content-Script-Type" content="text/javascript" />
	<title>Understanding OR mappings</title>
	<meta name="generator" content="Oracle DARB XHTML Converter (Mode = document) - Version 1.0.11" />
	<meta name="date" content="2012-12-19T9:17:39Z" />
	<meta name="robots" content="noarchive" />
	<meta name="doctitle" content="Understanding OR mappings" />
	<meta name="relnum" content="Release 3.2" />
	<meta name="partnum" content="Release 3.2" />
	<link rel="copyright" href="dcommon/html/cpyr.htm" title="Copyright" type="text/html" />
	<link rel="stylesheet" href="dcommon/css/blafdoc.css" title="Oracle BLAFDoc" type="text/css" />
	<link rel="contents" href="toc.htm" title="Contents" type="text/html" />
	<link rel="up" href="../../index.htm" title="Home" type="text/html" />
	<link rel="up" href="toc.htm" title="User Guide" type="text/html" />
	<link rel="up" href="concepts.htm" title="Concepts" type="text/html" />
	<link rel="up" href="concept_mapping.htm" title="Understanding OR mappings" type="text/html" />
	<link rel="index" href="index.htm" title="Index" type="text/html" />
	<link rel="prev" href="concept_persistence.htm" title="Understanding Java persistence " type="text/html" />
	<link rel="next" href="concepts001.htm" title="Understanding Java Persistence API" type="text/html" />
	</head>
	<body>
	<div class="header"><a id="top" name="top"></a>
	<div class="zz-skip-header"><a href="#BEGIN">Skip Headers</a></div>
	<table class="simple oac_no_warn" summary="" cellspacing="0" cellpadding="0" width="100%">
	<tr>
	<td align="left" valign="top"><b>Dali Java Persistence Tools User Guide</b><br />
	<b>Release 3.2</b><br />
	Release 3.2</td>
	<td valign="bottom" align="right">
	<table class="simple oac_no_warn" summary="" cellspacing="0" cellpadding="0" width="225">
	<tr>
	<td> </td>
	<td align="center" valign="top"><a href="../dali_user_guide.pdf"><img src="dcommon/gifs/pdf_icon.png" alt="PDF" height="24" /><br /><span class="icon">PDF</span></a></td><td align="center" valign="top"><a href="toc.htm"><img src="dcommon/gifs/toc.gif" alt="Go To Table Of Contents" /><br />
	<span class="icon">Contents</span></a></td>
	<td align="center" valign="top"><a href="index.htm"><img src="dcommon/gifs/index.gif" alt="Go To Index" /><br />
	<span class="icon">Index</span></a></td>
	</tr>
	</table>
	</td>
	</tr>
	</table>
	<hr />
	<table class="simple oac_no_warn" summary="" cellspacing="0" cellpadding="0" width="100">
	<tr>
	<td align="center"><a href="concept_persistence.htm"><img src="dcommon/gifs/leftnav.gif" alt="Previous" /><br />
	<span class="icon">Understanding Java persistence</span></a>  </td>
	<td align="center"><a href="concepts001.htm"><img src="dcommon/gifs/rightnav.gif" alt="Next" /><br />
	<span class="icon">Understanding Java Persistence API</span></a></td>
	<td> </td>
	</tr>
	</table>
	<p id="BREADCRUMBING"><a href="../../index.htm" title="Home">Home</a> > <a href="toc.htm" title="User Guide">User Guide</a> > <a href="concepts.htm" title="Concepts">Concepts</a> > Understanding OR mappings</p>
	<a name="BEGIN" id="BEGIN"></a></div>
	<!-- class="header" -->
	<div class="ind"><!-- End Header --><a id="BABBDJFI" name="BABBDJFI"></a>
	<div class="sect1">
	<h1 class="sect1">Understanding OR mappings</h1>
	<p><a id="sthref22" name="sthref22"></a><a id="sthref23" name="sthref23"></a>The Dali OR (object-relational) Mapping Tool allows you to describe how your entity objects <span class="italic">map</span> to the data source (or other objects). This approach isolates persistence information from the object model–developers are free to design their ideal object model, and DBAs are free to design their ideal schema.</p>
	<p>These mappings transform an object data member type to a corresponding relational database data source representation. These OR mappings can also transform object data members that reference other domain objects stored in other tables in the database and are related through foreign keys.</p>
	<p>You can use these mappings to map simple data types including primitives (such as <code>int</code>), JDK classes (such as <code>String</code>), and large object (LOB) values. You can also use them to transform object data members that reference other domain objects by way of association where data source representations require object identity maintenance (such as sequencing and back references) and possess various types of multiplicity and navigability. The appropriate mapping class is chosen primarily by the cardinality of the relationship.</p>
	<a id="sthref24" name="sthref24"></a>
	<p class="subhead2">Related tasks</p>
	<ul>
	<li>
	<p><a href="task_mapping.htm#BABDGBIJ">Mapping an entity</a></p>
	</li>
	</ul>
	</div>
	<!-- class="sect1" --></div>
	<!-- class="ind" -->
	<!-- Start Footer -->
	<div class="footer">
	<hr />
	<table class="simple oac_no_warn" summary="" cellspacing="0" cellpadding="0" width="100%">
	<col width="33%" />
	<col width="*" />
	<col width="33%" />
	<tr>
	<td valign="bottom">
	<table class="simple oac_no_warn" summary="" cellspacing="0" cellpadding="0" width="100">
	<col width="*" />
	<col width="48%" />
	<col width="48%" />
	<tr>
	<td> </td>
	<td align="center"><a href="concept_persistence.htm"><img src="dcommon/gifs/leftnav.gif" alt="Previous" /><br />
	<span class="icon">Understanding Java persistence</span></a>  </td>
	<td align="center"><a href="concepts001.htm"><img src="dcommon/gifs/rightnav.gif" alt="Next" /><br />
	<span class="icon">Understanding Java Persistence API</span></a></td>
	</tr>
	</table>
	</td>
	<td class="copyrightlogo"><img class="copyrightlogo" src="http://www.eclipse.org/eclipse.org-common/themes/Nova/images/eclipse.png" alt="Eclipse Logo" width="150"/><br />
	<span class="copyrightlogo">Copyright © 2011, 2012,&nbspby The Eclipse Foundation under the Eclipse Public License (EPL).</span> <a href="legal.htm"><br />
	<span class="copyrightlogo">Legal Notices</span></a></td>
	<td valign="bottom" align="right">
	<table class="simple oac_no_warn" summary="" cellspacing="0" cellpadding="0" width="225">
	<tr>
	<td> </td>
	<td align="center" valign="top"><a href="../dali_user_guide.pdf"><img src="dcommon/gifs/pdf_icon.png" alt="PDF" height="24" /><br /><span class="icon">PDF</span></a></td><td align="center" valign="top"><a href="toc.htm"><img src="dcommon/gifs/toc.gif" alt="Go To Table Of Contents" /><br />
	<span class="icon">Contents</span></a></td>
	<td align="center" valign="top"><a href="index.htm"><img src="dcommon/gifs/index.gif" alt="Go To Index" /><br />
	<span class="icon">Index</span></a></td>
	</tr>
	</table>
	</td>
	</tr>
	</table>
	</div>
	<!-- class="footer" -->
	</body>
	</html>