pyflink.datastream.data_stream.KeyedStream.key_by

KeyedStream.key_by(key_selector: Union[Callable, KeySelector], key_type: Optional[TypeInformation] = None) → KeyedStream

Creates a new KeyedStream that uses the provided key for partitioning its operator states.

Parameters

• key_selector – The KeySelector to be used for extracting the key for partitioning.

• key_type – The type information describing the key type.

Returns

The DataStream with partitioned state(i.e. KeyedStream).