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From Ning Shi <nings...@gmail.com>
Subject Re: Aggregator State in Keyed Windowed Stream
Date Mon, 10 Sep 2018 13:43:24 GMT
> Back to my first question, is the accumulator state backed by RocksDB state backend? If
so, I don’t need to use rich function for the aggregate function.

I did some testing and code reading. To answer my own question, the
accumulator state seems to be managed by RocksDB if I use it as the
state backend. The aggregate function is wrapped by
org.apache.flink.contrib.streaming.state.RocksDBAggregatingState. As
long as the accumulator is serializable, it will be stored in RocksDB.
So I don’t seem to need to use rich function here. Please correct me
if I’m wrong.


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