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<h1><a name="kanchor30"></a><a name="kanchor31"></a>Transparent Persistence</h1>
<p>One of db4o's goals is to make the database transparent to the
application logic. Wouldn't it be nice to initially register an
object with a single store()-call and then let the database manage all future object modifications? Transparent Persistence does exactly that.It keeps track of changes and stores all modified objects automatically when committing. </p>
<p>This has several benefits:</p>
<ul>
<li value="1">Clean an refactorable code. The code doesn't depend on the right activation-depth. </li>
<li value="2">Performance-benefits. Only the objects which are needed are loaded into memory. And only modified objects are stored.</li>
<li value="3">No changes can be lost due to miss configured update-depth.</li>
</ul>
<p>Transparent persistence takes care of activating the objects and storing changes. Take a look a simple example. <a href="transparent_persistence/transparent_persistence_example.htm" target="" title="" alt="" class="MCXref">See "Transparent Persistence Example"</a></p>
<p>In order to support transparent persistence the persisted object need to implement certain interfaces. To manually implementing this interface is time consuming. Therefore it can be automated with enhancement tools. <a href="transparent_persistence/tp_enhanced_example.htm" target="" title="" alt="" class="MCXref">See "TP Enhancement"</a></p>
<p>When using Transparent Persistence collections might need special attention. <a href="transparent_persistence/collection_example.htm" target="" title="" alt="" class="MCXref">See "Transparent Persistence Collections"</a></p>
<p>For a deeper understanding of the mechanism: <a href="transparent_persistence/transparent_persistence_implementation.htm" target="" title="" alt="" class="MCXref">See "Transparent Persistence Implementation"</a></p>
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