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Jason Dere updated HIVE-10673: ------------------------------ Attachment: HIVE-10673.7.patch Update unit tests > Dynamically partitioned hash join for Tez > ----------------------------------------- > > Key: HIVE-10673 > URL: https://issues.apache.org/jira/browse/HIVE-10673 > Project: Hive > Issue Type: New Feature > Components: Query Planning, Query Processor > Reporter: Jason Dere > Assignee: Jason Dere > Attachments: HIVE-10673.1.patch, HIVE-10673.2.patch, > HIVE-10673.3.patch, HIVE-10673.4.patch, HIVE-10673.5.patch, > HIVE-10673.6.patch, HIVE-10673.7.patch > > > Some analysis of shuffle join queries by [~mmokhtar]/[~gopalv] found about > 2/3 of the CPU was spent during sorting/merging. > While this does not work for MR, for other execution engines (such as Tez), > it is possible to create a reduce-side join that uses unsorted inputs in > order to eliminate the sorting, which may be faster than a shuffle join. To > join on unsorted inputs, we can use the hash join algorithm to perform the > join in the reducer. This will require the small tables in the join to fit in > the reducer/hash table for this to work. -- This message was sent by Atlassian JIRA (v6.3.4#6332)