command_cursor – Tools for iterating over MongoDB command results

command_cursor – Tools for iterating over MongoDB command results

CommandCursor class to iterate over command results.

class pymongo.commandcursor.CommandCursor(_collection, cursor_info, address, retrieved=0, batch_size=0, max_await_time_ms=None, session=None, explicit_session=False)
Create a new command cursor.

The parameter ‘retrieved’ is unused.

address
The (host, port) of the server used, or None.

New in version 3.0.

alive
Does this cursor have the potential to return more data?

Even if alive is True, next() can raiseStopIteration. Best to use a for loop:

for doc in collection.aggregate(pipeline):
    print(doc)

Note

alive can be True while iterating a cursor froma failed server. In this case alive will return False afternext() fails to retrieve the next batch of results from theserver.

batchsize(_batch_size)
Limits the number of documents returned in one batch. Each batchrequires a round trip to the server. It can be adjusted to optimizeperformance and limit data transfer.

Note

batch_size can not override MongoDB’s internal limits on theamount of data it will return to the client in a single batch (i.eif you set batch size to 1,000,000,000, MongoDB will currently onlyreturn 4-16MB of results per batch).

Raises TypeError if batch_size is not an integer.Raises ValueError if batch_size is less than 0.

Parameters:

- _batch_size_: The size of each batch of results requested.

close()
Explicitly close / kill this cursor.
cursor_id
Returns the id of the cursor.
next()
Advance the cursor.
session
The cursor’s ClientSession, or None.

New in version 3.6.

class pymongo.commandcursor.RawBatchCommandCursor(_collection, cursor_info, address, retrieved=0, batch_size=0, max_await_time_ms=None, session=None, explicit_session=False)
Create a new cursor / iterator over raw batches of BSON data.

Should not be called directly by application developers -see aggregate_raw_batches()instead.