Reposting the reply that was posted to dev mailing list :- For storm core, windowed bolts would give you the tuples in the last minute but you would have to do the grouping yourself. You could of-course use a fields grouping to split the load across the windowed bolts. For trident you might want to take a look at the windowing apis that were added recently and see if it fits your need. You have to choose between trident and core based on your use cases, the guarantee you need and if you need batching vs per tuple processing etc.
- Arun From: Maria Musterfrau Reply-To: "user@storm.apache.org<mailto:user@storm.apache.org>" Date: Wednesday, March 30, 2016 at 10:56 PM To: "user@storm.apache.org<mailto:user@storm.apache.org>" Subject: Fw: Combining group by and time window Does anyone have an idea? Thank you in advance. Regards, Daniela Gesendet: Montag, 28. März 2016 um 21:06 Uhr Von: "Maria Musterfrau" <daniela_4...@gmx.at<mailto:daniela_4...@gmx.at>> An: user@storm.apache.org<mailto:user@storm.apache.org> Betreff: Combining group by and time window Hi, I have a stream with time series data from different regions. I would like to group the stream by the different regions and to add up the values of the last minute (time window) per region. The sums should be persisted to Redis or something like this. I already found out that Storm Trident provides a group by function to split the stream. I think this could be useful. Storm core provides time windows, so I could use it for the aggregation. But how can I combine these two components? Or is this not possible? Would it be useful to do the grouping already in Kafka (with different topics) or is it better to do it in Storm Thank you in advance. Regards, Daniela
