public function __construct()
 {
     for ($i = 0; $i < 10; $i++) {
         $this->groupId = substr(md5(uniqid(rand(), true)), 0, 16);
         $selectBuilder = new Gpf_SqlBuilder_SelectBuilder();
         $selectBuilder->select->add(Gpf_Db_Table_QuickTasks::GROUPID);
         $selectBuilder->from->add(Gpf_Db_Table_QuickTasks::getName());
         $selectBuilder->where->add(Gpf_Db_Table_QuickTasks::GROUPID, '=', $this->groupId);
         if ($selectBuilder->getAllRows()->getSize() == 0) {
             break;
         }
     }
 }