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db4o-doc-8.0-1.fc15.i686.rpm

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    <head><title>Update Depth</title>
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        <h1>Update Depth</h1>
        <p>By default db4o only stores changes on the updated object but not the changes on referenced objects. With a higher update-depth db4o will traverse along the object graph to a certain depth and update all objects. <a href="../../basics/update_concept.htm" target="" title="" alt="" class="MCXref">See "Update Concept"</a></p>
        <p>With the update-depth you configure how deep db4o updates the object-graph. </p>
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            <pre class="prettyprint" xml:space="preserve">IEmbeddedConfiguration configuration = Db4oEmbedded.NewConfiguration();
configuration.Common.UpdateDepth = 2;</pre>
            <div class="codesnippet-meta">CommonConfigurationExamples.cs: Increasing the update-depth
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            <pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Dim configuration As IEmbeddedConfiguration = Db4oEmbedded.NewConfiguration()
configuration.Common.UpdateDepth = 2</pre>
            <div class="codesnippet-meta">CommonConfigurationExamples.vb: Increasing the update-depth
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        <p>A higher update depth is usually more convenient, because you don't need to explicitly store each changed object. However the higher the update depth is the more time it takes to update the objects. Therefore it is a tradeoff. Note that you can also use <a href="../../basics/update_concept/transparent_persistence.htm">transparent persistence</a>, which takes of updating the right objects.</p>
        <h2>Class Specific Configuration</h2>
        <p>You can also configure a class specific update depth. <a href="../objectclass_configuration.htm" target="" title="" alt="" class="MCXref">See "Class Specific Configuration"</a></p>
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            <pre class="prettyprint" xml:space="preserve">IEmbeddedConfiguration configuration = Db4oEmbedded.NewConfiguration();
configuration.Common.ObjectClass(typeof (Person)).UpdateDepth(2);</pre>
            <div class="codesnippet-meta">ObjectConfigurationExamples.cs: Set the update depth
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        <div class="codesnippet" MadCap:conditions="Primary.VB.NET">
            <pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Dim configuration As IEmbeddedConfiguration = Db4oEmbedded.NewConfiguration()
configuration.Common.ObjectClass(GetType(Person)).UpdateDepth(2)</pre>
            <div class="codesnippet-meta">ObjectConfigurationExamples.vb: Set the update depth
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