Hi Fabian, The link you sent is broken but I think you are referring the conversation with Viktor.
I agree that we should provide the same api for aggregations and I don’t think there is any reason why the proposed batch approach wouldn’t work on streaming :) When there is an agreement on the new aggregation api we will implement it for streaming. Cheers, Gyula > On 05 Nov 2014, at 19:26, Fabian Hueske <[email protected]> wrote: > > Hi Gyula, > > great to see so much progress with Flink Streaming! > > Regarding the improved aggregations, there is another effort to improve the > aggregations of the batch API, which was recently discussed on the mailing > list [1]. > I think it would make sense to try to keep the streaming and batch APIs > close together. Would the proposed batch approach also work for the > streaming case and if not what is missing? > > Cheers, Fabian > > [1] > http://mail-archives.apache.org/mod_mbox/flink-dev/201410.mbox/%3C44B1AB07-F993-436F-AE23-8CC4CCC08A54%40tu-berlin.de%3E > > 2014-11-05 18:37 GMT+01:00 Gyula Fóra <[email protected]>: > >> Hey guys, >> >> Just a quick note on some upcoming API updates for the Streaming api. >> >> Now it will be possible to use field expressions for both grouping and >> aggregations in the streaming api. You can check it out here >> < >> https://github.com/mbalassi/incubator-flink/blob/daba36e142537ca0bd7e4d0f1209ce8b0ebecda5/flink-addons/flink-streaming/flink-streaming-examples/src/main/java/org/apache/flink/streaming/examples/wordcount/PojoWordCount.java#L102 >>> >> . >> >> Or in a concise form: >> DataStream<Word> counts = text.flatMap(new Tokenizer()).groupBy("word") >> .sum("frequency"); >> >> I will still do some more testing before it will be available in the master >> branch. >> >> I am also planning to extend aggregations to more fields at the same time >> like >> sum(1,2,2) or max("a","c"). >> >> Regards, >> Gyula >>
