diff --git a/core/dbsearch.class.php b/core/dbsearch.class.php
index ce74950ba..cbc340eed 100644
--- a/core/dbsearch.class.php
+++ b/core/dbsearch.class.php
@@ -298,7 +298,7 @@ abstract class DBSearch
 	/**
 	 * @param string $sQuery
 	 * @param array $aParams
-	 * @return DBSearch
+	 * @return self
 	 * @throws OQLException
 	 */
 	static public function FromOQL($sQuery, $aParams = null)
diff --git a/pages/audit.php b/pages/audit.php
index b15da1aaf..5e52c1494 100644
--- a/pages/audit.php
+++ b/pages/audit.php
@@ -1,5 +1,5 @@
 <?php
-// Copyright (C) 2010-2017 Combodo SARL
+// Copyright (C) 2010-2018 Combodo SARL
 //
 //   This file is part of iTop.
 //
@@ -23,11 +23,15 @@
  * @license     http://opensource.org/licenses/AGPL-3.0
  */
 /**
- * Adds the context parameters to the audit query
- * @param DBSearch $oFilter
+ * Adds the context parameters to the audit rule query
+ *
+ * @param DBObjectSearch $oFilter
  * @param ApplicationContext $oAppContext
+ *
+ * @throws \CoreException
+ * @throws \CoreWarning
  */
-function FilterByContext(DBSearch &$oFilter, ApplicationContext $oAppContext)
+function FilterByContext(DBObjectSearch &$oFilter, ApplicationContext $oAppContext)
 {
 	$sObjClass = $oFilter->GetClass();		
 	$aContextParams = $oAppContext->GetNames();
@@ -86,6 +90,16 @@ function FilterByContext(DBSearch &$oFilter, ApplicationContext $oAppContext)
 	}
 }
 
+/**
+ * @param int $iRuleId Audit rule ID
+ * @param DBObjectSearch $oDefinitionFilter Created from the audit category's OQL
+ * @param ApplicationContext $oAppContext
+ *
+ * @return mixed
+ * @throws \ArchivedObjectException
+ * @throws \CoreException
+ * @throws \OQLException
+ */
 function GetRuleResultFilter($iRuleId, $oDefinitionFilter, $oAppContext)
 {
 	$oRule = MetaModel::GetObject('AuditRule', $iRuleId);
@@ -102,6 +116,7 @@ function GetRuleResultFilter($iRuleId, $oDefinitionFilter, $oAppContext)
 	else
 	{
 		// The query returns only the valid elements, all the others are invalid
+		// Warning : we're generating a `WHERE ID IN`... query, and this could be very slow if there are lots of id !
 		$aValidRows = $oRuleFilter->ToDataArray(array('id'));
 		$aValidIds = array();
 		foreach($aValidRows as $aRow)
@@ -415,4 +430,3 @@ catch(Exception $e)
 		IssueLog::Error($e->getMessage());
 	}
 }
-?>