public static function ExtractSelectedSubmission($data, $singleResult = false, $SelectedSubmissionExtension = '', $isResult = true)
 {
     // generates an assoc array of selected entry's by using a defined list of
     // its attributes
     $res = DBJson::getResultObjectsByAttributes($data, SelectedSubmission::getDBPrimaryKey(), SelectedSubmission::getDBConvert(), $SelectedSubmissionExtension);
     if ($isResult) {
         $res = SelectedSubmission::decodeSelectedSubmission($res, false);
         if ($singleResult == true) {
             // only one object as result
             if (count($res) > 0) {
                 $res = $res[0];
             }
         }
     }
     return $res;
 }