diff --git a/framework/db/schema/CDbCriteria.php b/framework/db/schema/CDbCriteria.php
index <HASH>..<HASH> 100644
--- a/framework/db/schema/CDbCriteria.php
+++ b/framework/db/schema/CDbCriteria.php
@@ -11,6 +11,14 @@
 /**
  * CDbCriteria represents a query criteria, such as conditions, ordering by, limit/offset.
  *
+ * It can be used in AR query methods such as CActiveRecord::find and CActiveRecord::findAll.
+ *
+ * $criteria=new CDbCriteria();
+ * $criteria->compare('status',Post::STATUS_ACTIVE);
+ * $criteria->addInCondition('id',array(1,2,3,4,5,6));
+ *
+ * $posts = Post::model()->findAll($criteria);
+ *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @version $Id$
  * @package system.db.schema
Added usage example to CDbCriteria phpdoc