jcamachor commented on a change in pull request #819: HIVE-22363 ReduceDeduplication may leave an invalid GroupByOperator behind in some cases URL: https://github.com/apache/hive/pull/819#discussion_r337640161
########## File path: ql/src/test/results/clientpositive/llap/explainuser_1.q.out ########## @@ -4990,38 +4990,44 @@ Vertex dependency in root stage Reducer 2 <- Map 1 (SIMPLE_EDGE) Reducer 3 <- Reducer 2 (SIMPLE_EDGE) Reducer 4 <- Reducer 3 (SIMPLE_EDGE) +Reducer 5 <- Reducer 4 (SIMPLE_EDGE) Review comment: Since the plan is a user explain, it does not show the sorting keys in the shuffle. However, group by operator produces correct results if we partition data by first column and sort by the three grouping columns. I believe that is what was happening here. The additional shuffle phase is unnecessary. ---------------------------------------------------------------- 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: [email protected] With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
