Hello Baki, It looks like option 2 is really what you want. The purpose of the time window stores is to allow deleting old data when you need to group by a time dimension, which naturally results in an infinite key space.
If you don’t want to wait for the final result, can you just not add the suppression? It’s only purpose is to _not_ emit any data until _after_ the grace period expires. Without it, streams will still respect the grace period by updating the result whenever there is late arriving data. Lastly, that is a check for overflow. The timestamp is supposed to be a timestamp in milliseconds since the epoch. If you’re getting an overflow, it means your time stamps are from the far future. You might want to manually inspect them. I hope this helps, John On Sun, May 10, 2020, at 05:29, Baki Hayat wrote: > Hello Friends, > > I wrote into stackoverflow but also i am writing here, > > I have couple of questions about window operation, grace period and late > events. > > Could you please check my problem about group by with adding time field as > a key or window by and group by without time field ? > > Here is detail explanation... > > https://stackoverflow.com/questions/61680407/kafka-streams-groupby-late-event-persistentwindowstore-windowby-with-gra >