Thanks Rong, I will look at the links you mentioned.
On Wed, May 22, 2019 at 10:39 AM Rong Rong <walter...@gmail.com> wrote: > Hi Miki, > > Upon trigger, window will be fired with all of its content in its state > invoking the "emitWindowContent" method. which will further invoke the > window function you define. > Thus if your goal is to only emit the delta, one thing is to do so in your > window function. One challenge you might face is how to make your window > function stateful, you might want to checkout this document[1] for more > details. > > If your goal is to limit the number of content stored in the window state > to only the delta. you can also look at incremental aggregation state [2] > of the window, but you will have to design your window function in such a > way that it can take delta into account. > > -- > Rong > > [1] > https://ci.apache.org/projects/flink/flink-docs-stable/dev/stream/operators/windows.html#processwindowfunction > [2] > https://ci.apache.org/projects/flink/flink-docs-stable/dev/stream/operators/windows.html#processwindowfunction-with-incremental-aggregation > > > On Sun, May 19, 2019 at 8:00 PM Congxian Qiu <qcx978132...@gmail.com> > wrote: > >> Hi, Nikhil >> Window will emit all state to downstream. Can you clear the state while >> triggering? >> >> Nikhil Goyal <nownik...@gmail.com>于2019年5月19日 周日01:03写道： >> >>> I have window of 1 hour and trigger of 5 min. I want to know if every 5 >>> min Flink is writing the entire window or only the keys which changed. >>> >>> On Sat, May 18, 2019, 9:40 AM miki haiat <miko5...@gmail.com> wrote: >>> >>>> Can you elaborate more what is you use case ? >>>> >>>> >>>> On Sat, May 18, 2019 at 12:47 AM Nikhil Goyal <nownik...@gmail.com> >>>> wrote: >>>> >>>>> Hi guys, >>>>> >>>>> Is there a way in Flink to only propagate the changes which happened >>>>> in the window's state rather than dumbing the contents of the window again >>>>> and again upon trigger? >>>>> >>>>> Thanks >>>>> Nikhil >>>>> >>>> -- >> Best, >> Congxian >> >
