diff --git a/modules/monitoring/library/Monitoring/Backend/Ido/Query/ServicenotificationQuery.php b/modules/monitoring/library/Monitoring/Backend/Ido/Query/ServicenotificationQuery.php
index 9a99b6152..bf7e99259 100644
--- a/modules/monitoring/library/Monitoring/Backend/Ido/Query/ServicenotificationQuery.php
+++ b/modules/monitoring/library/Monitoring/Backend/Ido/Query/ServicenotificationQuery.php
@@ -133,12 +133,12 @@ class ServicenotificationQuery extends IdoQuery
      */
     protected function joinContactnotifications()
     {
-        $this->select->join(
+        $this->select->joinLeft(
             array('cn' => $this->prefix . 'contactnotifications'),
             'cn.notification_id = sn.notification_id',
             array()
         );
-        $this->select->join(
+        $this->select->joinLeft(
             array('cno' => $this->prefix . 'objects'),
             'cno.object_id = cn.contact_object_id',
             array()