HeartSaVioR opened a new pull request #31986: URL: https://github.com/apache/spark/pull/31986
Introduction: this PR is a part of SPARK-10816 (`EventTime based sessionization (session window)`). Please refer #31937 to see the overall view of the code change. (Note that code diff could be diverged a bit.) ### What changes were proposed in this pull request? This PR introduces UpdatingSessionsIterator, which analyzes neighbor elements and adjust session information on elements. UpdatingSessionsIterator calculates and updates the session window for each element in the given iterator, which makes elements in the same session window having same session spec. Downstream can apply aggregation to finally merge these elements bound to the same session window. UpdatingSessionsIterator works on the precondition that given iterator is sorted by "group keys + start time of session window", and the iterator still retains the characteristic of the sort. UpdatingSessionsIterator copies the elements to safely update on each element, as well as buffers elements which are bound to the same session window. Due to such overheads, MergingSessionsIterator which will be introduced via SPARK-34889 should be used whenever possible. This PR also introduces UpdatingSessionsExec which is the physical node on leveraging UpdatingSessionsIterator to sort the input rows and updates session information on input rows. ### Why are the changes needed? This part is a one of required on implementing SPARK-10816. ### Does this PR introduce _any_ user-facing change? No. ### How was this patch tested? New test suite added. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org
