[ https://issues.apache.org/jira/browse/HIVE-3464?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Phabricator updated HIVE-3464: ------------------------------ Attachment: HIVE-3464.D5409.4.patch navis updated the revision "HIVE-3464 [jira] Merging join tree may reorder joins which could be invalid". Rebased to trunk Reviewers: JIRA REVISION DETAIL https://reviews.facebook.net/D5409 CHANGE SINCE LAST DIFF https://reviews.facebook.net/D5409?vs=23079&id=30549#toc AFFECTED FILES ql/src/java/org/apache/hadoop/hive/ql/parse/SemanticAnalyzer.java ql/src/test/queries/clientpositive/mergejoins_mixed.q ql/src/test/results/clientpositive/join_filters_overlap.q.out ql/src/test/results/clientpositive/mergejoins_mixed.q.out To: JIRA, navis Cc: njain > Merging join tree may reorder joins which could be invalid > ---------------------------------------------------------- > > Key: HIVE-3464 > URL: https://issues.apache.org/jira/browse/HIVE-3464 > Project: Hive > Issue Type: Bug > Components: Query Processor > Affects Versions: 0.10.0 > Reporter: Navis > Assignee: Navis > Attachments: HIVE-3464.D5409.2.patch, HIVE-3464.D5409.3.patch, > HIVE-3464.D5409.4.patch > > > Currently, hive merges join tree from right to left regardless of join types, > which may introduce join reordering. For example, > select * from a join a b on a.key=b.key join a c on b.key=c.key join a d on > a.key=d.key; > Hive tries to merge join tree in a-d=b-d, a-d=a-b, b-c=a-b order and a-d=a-b > and b-c=a-b will be merged. Final join tree is "a-(bdc)". > With this, ab-d join will be executed prior to ab-c. But if join type of -c > and -d is different, this is not valid. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira