function delete($id)
 {
     if (!is_array($id)) {
         $id = array($id);
     }
     $data = $this->_db()->where_in('id', $id)->get($this->_name)->result_array();
     parent::delete($id);
     $now = date('Y-m-d H:i:s');
     $user = $this->auth->get_user();
     foreach ($data as $row) {
         $row['activity'] = 'delete';
         $row['updated_time'] = $now;
         $row['updated_by'] = $user['id'];
         $row['status'] = '-1';
         $this->save_history($row, $row['id']);
     }
 }