/**
  * delete group and all related data
  *
  * @access	public
  * @return	boolean	true if all object data were removed; false if only a references were removed
  */
 public function delete()
 {
     global $ilDB, $ilAppEventHandler;
     // always call parent delete function first!!
     if (!parent::delete()) {
         return false;
     }
     $query = "DELETE FROM grp_settings " . "WHERE obj_id = " . $ilDB->quote($this->getId(), 'integer');
     $res = $ilDB->manipulate($query);
     include_once './Modules/Group/classes/class.ilGroupParticipants.php';
     ilGroupParticipants::_deleteAllEntries($this->getId());
     $ilAppEventHandler->raise('Modules/Group', 'delete', array('object' => $this, 'obj_id' => $this->getId(), 'appointments' => $this->prepareAppointments('delete')));
     return true;
 }