Attempt to fetch at least one more record.

        :returns: number of records fetched

def fetch(self):
        """ Attempt to fetch at least one more record.

        :returns: number of records fetched
        """
        from neobolt.exceptions import ConnectionExpired
        if self._connection:
            try:
                detail_count, _ = self._connection.fetch()
            except ConnectionExpired as error:
                raise SessionExpired(*error.args)
            else:
                return detail_count
        return 0