cursor.py 文件源码

def batch_size(self, batch_size: int) -> 'Cursor':
        """Limits the number of documents returned in one batch. Each batch
        requires a round trip to the server. It can be adjusted to optimize
        performance and limit data transfer.

        .. note:: batch_size can not override MongoDB's internal limits on the
           amount of data it will return to the client in a single batch (i.e
           if you set batch size to 1,000,000,000, MongoDB will currently only
           return 4-16MB of results per batch).

        Raises :exc:`TypeError` if `batch_size` is not an integer.
        Raises :exc:`ValueError` if `batch_size` is less than ``0``.
        Raises :exc:`~pymongo.errors.InvalidOperation` if this
        :class:`Cursor` has already been used. The last `batch_size`
        applied to this cursor takes precedence.

        :Parameters:
          - `batch_size`: The size of each batch of results requested.
        """
        if not isinstance(batch_size, int):
            raise TypeError('batch_size must be an integer')
        if batch_size < 0:
            raise ValueError('batch_size must be >= 0')
        self.__check_okay_to_chain()

        self.__batch_size = batch_size
        return self