Hi,
I think you could try something like this
firstStream
.coGroup(secondStream)
.where(_.id)
.equalTo(_.id)
.window(TumblingEventTimeWindows.of(Time.seconds(1)))
.with(new MyCogroupFunction())
.uid("myCoGroup")
Best,
Guowei
On Fri, Jan 22, 2021 at 4:33 AM Sudharsan R <sud.r...@gmail.com> wrote:
> Is this comment in the file
> flink-streaming-java/src/main/java/org/apache/flink/streaming/api/datastream/CoGroupedStreams.java
> accurate?
>
> " * <p>Note: Right now, the groups are being built in memory so you need
> to ensure that they don't
> * get too big. Otherwise the JVM might crash."
>
> Looking at the source code of CoGroupedStreams, i see that it simply does
> a map, union and then the data is assigned to appropriate windows. I
> assumed that the persistence of elements in the window itself is done using
> my configured state backend (and that appends do not need to read the
> entire list state).
>
> I ask because i tried setting a uid on my cogroup operator like below and
> this results in a compilation error(no uid method available?)
>
> firstStream
> .coGroup(secondStream)
> .where(_.id)
> .equalTo(_.id)
> .window(TumblingEventTimeWindows.of(Time.seconds(1)))
> .apply(new MyCogroupFunction())
> .uid("myCogroup")
>
>
> Is the comment referring to having enough memory on the read side? If so,
> isn't this true for any window process function?
>
> Thanks
> Sudharsan
>
