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Hudson commented on HIVE-4845: ------------------------------ ABORTED: Integrated in Hive-trunk-hadoop2 #291 (See [https://builds.apache.org/job/Hive-trunk-hadoop2/291/]) HIVE-4845 : Correctness issue with MapJoins using the null safe operator (Brock Noland via Ashutosh Chauhan) (hashutosh: http://svn.apache.org/viewcvs.cgi/?root=Apache-SVN&view=rev&rev=1503818) * /hive/trunk/ql/src/java/org/apache/hadoop/hive/ql/exec/persistence/MapJoinDoubleKeys.java * /hive/trunk/ql/src/java/org/apache/hadoop/hive/ql/exec/persistence/MapJoinObjectKey.java * /hive/trunk/ql/src/test/org/apache/hadoop/hive/ql/exec/persistence * /hive/trunk/ql/src/test/org/apache/hadoop/hive/ql/exec/persistence/TestMapJoinKeys.java * /hive/trunk/ql/src/test/results/clientpositive/join_nullsafe.q.out > Correctness issue with MapJoins using the null safe operator > ------------------------------------------------------------ > > Key: HIVE-4845 > URL: https://issues.apache.org/jira/browse/HIVE-4845 > Project: Hive > Issue Type: Bug > Reporter: Brock Noland > Assignee: Brock Noland > Priority: Critical > Fix For: 0.12.0 > > Attachments: HIVE-4845.patch, HIVE-4845.patch, HIVE-4845.patch > > > I found a correctness issue while working on HIVE-4838. The following query > from join_nullsafe.q gives different results depending on if it's executed > map-side or reduce-side: > {noformat} > SELECT /*+ MAPJOIN(a) */ * FROM smb_input1 a JOIN smb_input1 b ON a.key <=> > b.key AND a.value <=> b.value ORDER BY a.key, a.value, b.key, b.value; > {noformat} > For that query, on the map side, rows which should be joined are not. For > example, the reduce side outputs this row: > {noformat} > a.key a.value b.key b.value > 148 NULL 148 NULL > {noformat} > which makes sense since a.key is equal to b.key and a.value is equal to > b.value but the current map-side code omits this row. The reason is that > MapJoinDoubleKey is used for the map-side join which doesn't properly compare > null values. -- 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