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<h1>How To Use Defragmentation</h1>
<p>The simplest way to defragment a db4o file would be:</p>
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<pre class="prettyprint" xml:space="preserve">Defragment.Defrag("database.db4o");</pre>
<div class="codesnippet-meta">DefragmentationExample.cs: Simplest possible defragment use case
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<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Defragment.Defrag("database.db4o")</pre>
<div class="codesnippet-meta">DefragmentationExample.vb: Simplest possible defragment use case
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<p>Ensure that the file is not opened by any other process or db4o instance. </p>
<p>This moves the file <i>filename </i>to <i>filename.backup</i>,
then it create a defragmented version of this database at the original position. If
the backup file already exists this an IOException is throw and no action
will be taken.</p>
<p>You can also specify the backup filename manually:</p>
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<pre class="prettyprint" xml:space="preserve">Defragment.Defrag("database.db4o", "database.db4o.bak");</pre>
<div class="codesnippet-meta">DefragmentationExample.cs: Specify backup file explicitly
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<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Defragment.Defrag("database.db4o", "database.db4o.bak")</pre>
<div class="codesnippet-meta">DefragmentationExample.vb: Specify backup file explicitly
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<p>For more detailed configuration of the defragmentation
process, you can use a <a href="defragmentation_configuration.htm">DefragmentConfig</a> instance:</p>
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<pre class="prettyprint" xml:space="preserve">DefragmentConfig config = new DefragmentConfig("database.db4o");
Defragment.Defrag(config);</pre>
<div class="codesnippet-meta">DefragmentationExample.cs: Defragment with configuration
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<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Dim config As New DefragmentConfig("database.db4o")
Defragment.Defrag(config)</pre>
<div class="codesnippet-meta">DefragmentationExample.vb: Defragment with configuration
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<p>It's possible to use a more fine grained configuration for the deframentation process. <a href="defragmentation_configuration.htm" target="" title="" alt="" class="MCXref" xrefformat="See "{paratext}"">See "Defragmentation Configuration"</a></p>
<p>Defragmentation can throw IOException in the following
situations:</p>
<ul>
<li value="1">Backup file exists.</li>
<li value="2">Database file not found.</li>
<li value="3">Database file is opened by another process.</li>
</ul>
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