public function rollback(Garp_Model $model, array $primaryKeys) {
        if (empty($primaryKeys)) {
            return;
        }
        $primaryCols = (array)$model->info(Zend_Db_Table::PRIMARY);
        $where = array();
        foreach ($primaryKeys as $pk) {
            $recordWhere = array();
            foreach ((array)$pk as $i => $key) {
                $recordWhere[] = $model->getAdapter()->quoteIdentifier(current($primaryCols)).' = '.
                                 $model->getAdapter()->quote($key);
            }
            $recordWhere = implode(' AND ', $recordWhere);
            $recordWhere = '('.$recordWhere.')';
            $where[] = $recordWhere;
            reset($primaryCols);
        }
        $where = implode(' OR ', $where);
        if (empty($where)) {
            return;
        }
        $model->delete($where);
    }