[ https://issues.apache.org/jira/browse/SPARK-33486?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Apache Spark reassigned SPARK-33486: ------------------------------------ Assignee: Apache Spark > Collapse Partial and Final Aggregation into Complete Aggregation mode > --------------------------------------------------------------------- > > Key: SPARK-33486 > URL: https://issues.apache.org/jira/browse/SPARK-33486 > Project: Spark > Issue Type: Task > Components: SQL > Affects Versions: 2.3.4, 2.4.7, 3.0.0, 3.0.1 > Reporter: Prakhar Jain > Assignee: Apache Spark > Priority: Major > > We should merge the Partial and Final Aggregation into one if there is no > exchange between them. > > Example: select col1, max(col2) from t1 join t2 on col1 group by col1 > In this case, after the SortMergeJoin, Spark will do PartialAggregation and > then FinalAggregation. So it will create HashTables two times which is not > required. If there is lot of data after Join with many distinct col1's then > there is a possibility of Spill also in HashAggregateExec. So Spill will also > happen twice which can be avoided. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org