def prepare(self, params=None):

        self._append((FIELD_INT, self.get_transaction_id()))
        self._append((FIELD_BOOLEAN, True))

        for k, v in enumerate(self._operation_stack):
            self._append((FIELD_BYTE, chr(1)))  # start of records
            for field in v:
                self._append(field)

        self._append((FIELD_BYTE, chr(0)))
        self._append((FIELD_STRING, ""))

        return super(_TXCommitMessage, self).prepare()