Cluster internal protocol representing a command request.

Cluster internal protocol representing a reply to an OP_COMMAND.

Delete documents.

Get more data from a query.

Insert new document.

Notify database that the client has finished with the cursor.

Send a message using the format introduced in MongoDB 3.6.

Query a collection.

Reply to a client request.

Update document.

Formerly used for OP_GET_BY_OID.