public function postDelMsgTypeColumn()
 {
     $validator = Validator::make(array('id' => Input::get('type_id')), $this->validate_id_arr);
     if ($validator->fails()) {
         return "Invalid notification type ID";
     }
     $type_id = Input::get('type_id');
     $column_id = Input::get('column_id');
     try {
         $column = MessageTypeColums::find($column_id);
         $column->delete();
         return json_encode(array(true, "Notification type column deleted successfully"));
     } catch (Exception $e) {
         return json_encode(array(false, "Can't delete notification type column"));
     }
 }