I'm trying to do a simple DataStream to DataStream join. Have two kafka topics that has common field. I'm trying to join by via keyBy-join-where-equalTo-TumblingWindow API in Flink 1.4.1.
My tumbling window size is 1 day. There will be more data than machine has memory. I know that Flink uses RocksDB to store state of the window. Will Flink use RocksDB to join between windows and not use HashMap for the merge operation?