Hi John I've seen other people have the same problem to solve, the following is their solution: union the two Datastreams, then use ProcsssFunction[1] to solve this, will also register timers to do GC things.
[1] https://ci.apache.org/projects/flink/flink-docs-stable/dev/stream/operators/process_function.html Best, Congxian John Tipper <john_tip...@hotmail.com> 于2019年6月14日周五 下午3:24写道： > Hi All, > > > I have 2 streams of events that relate to a common base event, where one > stream is the result of a flatmap. I want to join all events that share a > common identifier. > > Thus I have something that looks like: > > DataStream<TypeA> streamA = ... > DataStream<TypeB> streamB = someDataStream.flatMap(...) // produces stream of > TypeB for each item in someDataStream > > Both TypeA and TypeB share an identifier and I know how many TypeB objects > there are in the parent object. I want to perform some processing when all > of the events associated with a particular identifier have arrived, i.e. > when I basically can create a Tuple3<id, TypeA, List<TypeB>> object. > > Is this best done with a WindowJoin and a GlobalWindow, a Window CoGroup and > a GlobalWindow or by connecting the 2 streams into a ConnectedStream then > performing the joining inside a CoProcessFunction? > > Many thanks, > > John >
