diff --git a/library/Icinga/Data/Db/DbQuery.php b/library/Icinga/Data/Db/DbQuery.php
index b701f3ac0..a759da6b5 100644
--- a/library/Icinga/Data/Db/DbQuery.php
+++ b/library/Icinga/Data/Db/DbQuery.php
@@ -117,7 +117,7 @@ class DbQuery extends SimpleQuery
         return $select;
     }
 
-    protected function applyFilterSql($query)
+    public function applyFilterSql($query)
     {
         $where = $this->renderFilter($this->filter);
         if ($where !== '') {