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<h1>Collections Update Depth</h1>
<p>When you work with collections you should pay a special
attention to your update depth setting, as the performance impact of this
setting increases with the number of objects in the collection.</p>
<p>For example let’s consider a class like this:</p>
<span name="cs_wiki_filter" csw_filters="cs">
<p>c#:</p>
<p><code>class ListObject {</code></p>
<p><code> List
<DataObject> data;</code></p>
<p><code>}</code></p>
<p></span></p>
<span name="cs_wiki_filter" csw_filters="vb">
<p>VB:</p>
<p><code>Class ListObject </code><br></p>
<p><code> data As List(Od DataObject)</code></p>
<p><code>End Class</code></p>
</span>
<p>Let’s assume that ListObject has a data list of 1000 DataObjects.</p><p><b>Update depth = 1</b></p>
<p>data field object (List) will be updated if ListObject is saved.</p><p><b>Update depth = 2</b></p>
<p>data object (List) and all 1000 DataObjects in the list will be updated if
ListObject is saved.</p><p>It is easy to see that after a certain update depth value
all the list objects are getting updated, which produces a serious performance
penalty. The following examples show how to avoid the performance drop
and still get the expected results.</p>
<p><div class="childTopicList">More Reading:<ul>
<li><p><a href="collections_update_depth/insert_and_remove.html" class="wikiLink">Insert And Remove</a></p></li>
<li><p><a href="collections_update_depth/updating_list_objects.html" class="wikiLink">Updating List Objects</a></p></li>
</ul></div>
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This revision (4) was last Modified 2007-02-22T13:06:38 by Tetyana.
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