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<h1>Dangerous Practices</h1>
<p>db4o lets you <a href="../../configuration.htm">configure</a> a lot of low level details. It even lets you configure things which endanger the safety of the database integrity and transaction integrity. You should avoid these settings and only use them in very special cases.</p>
<p>One dangerous setting is disabling file-flushes. When you add the non-flushing decorator you get better performance. However due to the missing file-flushes, the <span class="MCPopup"><a href="javascript:void(0);" class="MCPopupSpot" onclick="FMCPopup( event, this ); return false;" MadCap:src="../acid_and_transactions.htm">ACID<img style="border: none;margin-left: 5px;" src="../../SkinSupport/ExpandingClosed.gif" MadCap:altsrc="../../SkinSupport/ExpandingOpen.gif" class="MCExpandingIcon" onload="if ( typeof( FMCPreloadImage ) == 'function' ) { FMCPreloadImage( '../../SkinSupport/ExpandingOpen.gif' ); }" /></a></span>-properties cannot be guaranteed. </p>
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<pre class="prettyprint" xml:space="preserve">IStorage fileStorage = new FileStorage();
configuration.File.<span class="MCPopup"><a href="javascript:void(0);" class="MCPopupSpot" onclick="FMCPopup( event, this ); return false;" MadCap:src="../../configuration/file/storage.htm">Storage<img style="border: none;margin-left: 5px;" src="../../SkinSupport/ExpandingClosed.gif" MadCap:altsrc="../../SkinSupport/ExpandingOpen.gif" class="MCExpandingIcon" onload="if ( typeof( FMCPreloadImage ) == 'function' ) { FMCPreloadImage( '../../SkinSupport/ExpandingOpen.gif' ); }" /></a></span> = new NonFlushingStorage(fileStorage);</pre>
<div class="codesnippet-meta">DangerousPractises.cs: Using the non-flushing storage weakens the ACID-properties
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<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Dim fileStorage As IStorage = New FileStorage()
configuration.File.Storage = New NonFlushingStorage(fileStorage)</pre>
<div class="codesnippet-meta">DangerousPractises.vb: Using the non-flushing storage weakens the ACID-properties
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<p>Another setting which endangers the ACID properties is disabling the commit-recovery. This setting should only be
used in emergency situations after consulting db4o support. The ACID flow of
the commit can be re-enabled after restoring the original configuration.</p>
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<pre class="prettyprint" xml:space="preserve">configuration.File.DisableCommitRecovery();</pre>
<div class="codesnippet-meta">DangerousPractises.cs: Disabling commit-recovery weakens the ACID-properties
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<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">configuration.File.DisableCommitRecovery()</pre>
<div class="codesnippet-meta">DangerousPractises.vb: Disabling commit-recovery weakens the ACID-properties
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