Hi! I'm working on a join setup that does fuzzy matching in case the client does not send enough parameters to join by a foreign key. There's a few ways I can store the state. I'm curious about best practices around this. I'm using rocksdb as the state storage.
I was reading the code for IntervalJoin <https://github.com/apache/flink/blob/master/flink-streaming-java/src/main/java/org/apache/flink/streaming/api/operators/co/IntervalJoinOperator.java> and was a little shocked by the implementation. It feels designed for very short join intervals. I read this set of pages <https://ci.apache.org/projects/flink/flink-docs-stable/dev/stream/state/state.html> but I'm looking for one level deeper. E.g. what are performance characteristics of different types of state crud operations with rocksdb? E.g. I could create extra MapState to act as an index. When is this worth it?
