Hi:
Apache Flink documentation
(https://ci.apache.org/projects/flink/flink-docs-release-1.4/dev/stream/operators/index.html)
indicates that a reduce function on a KeyedStream as follows:
A "rolling" reduce on a keyed data stream. Combines the current element with
the last reduced value and emits the new value.
A reduce function that creates a stream of partial sums:keyedStream.reduce(new
ReduceFunction<Integer>() {
@Override
public Integer reduce(Integer value1, Integer value2)
throws Exception {
return value1 + value2;
}
});
The KeyedStream is not windowed, so when does the reduce function kick in to
produce the DataStream (ie, is there a default time out, or collection size
that triggers it, since we have not defined any window on it).
Thanks
Mans
