Hi Amol,
I'm not sure whether this is impossible, especially when you need to operate the record in multi parallelism. IMO, in theroy, we can only get a ordered stream when there is a single partition of kafka and operate it with a single parallelism in flink. Even in this case, if you only want to order the records in a window, than you need to store the records in the state, and order them when the window is triggered. But if you want to order the records with a single `keyBy()`(non-window), I think that's maybe impossible in practice, because you need to store the all the incoming records and order the all data for every incoming records, also you need to send retracted message for the previous result(because every incoming record might change the global order of the records). Best, Sihua On 06/19/2018 19:19，Amol S - iProgrammer<am...@iprogrammer.com> wrote： Hi, I have used flink streaming API in my application where the source of streaming is kafka. My kafka producer will publish data in ascending order of time in different partitions of kafka and consumer will read data from these partitions. However some kafka partitions may be slow due to some operation and produce late results. Is there any way to maintain order in this stream though the data arrive out of order. I have tried BoundedOutOfOrdernessTimestampExtractor but it didn't served the purpose. While digging this problem I came across your documentation (URL: https://cwiki.apache.org/confluence/display/FLINK/Time+and+Order+in+Streams) and tried to implement this but it didnt worked. I also tried with Table API order by but it seems you not support orderBy in flink 1.5 version. Please suggest me any workaround for this. I have raised same concern on stack overflow https://stackoverflow.com/questions/50904615/ordering-of-streams-while-reading-data-from-multiple-kafka-partitions Thanks, ----------------------------------------------- *Amol Suryawanshi* Java Developer am...@iprogrammer.com *iProgrammer Solutions Pvt. Ltd.* *Office 103, 104, 1st Floor Pride Portal,Shivaji Housing Society, Bahiratwadi,Near Hotel JW Marriott, Off Senapati Bapat Road, Pune - 411016, MH, INDIA.**Phone: +91 9689077510 | Skype: amols_iprogrammer* www.iprogrammer.com <sac...@iprogrammer.com> ------------------------------------------------
