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Vineet Garg commented on HIVE-21537: ------------------------------------ [~jcamachorodriguez] Can you take a look? [https://github.com/apache/hive/pull/583] > Scalar query rewrite could be improved to not generate an extra join if > subquery is guaranteed to produce atmost one row > ------------------------------------------------------------------------------------------------------------------------ > > Key: HIVE-21537 > URL: https://issues.apache.org/jira/browse/HIVE-21537 > Project: Hive > Issue Type: Improvement > Components: Query Planning > Affects Versions: 4.0.0 > Reporter: Vineet Garg > Assignee: Vineet Garg > Priority: Major > Labels: sub-query > Attachments: HIVE-21537.1.patch, HIVE-21537.2.patch > > > Currently Hive planner introduces this branch and later executes a rule to > remove this branch if it could. > Subquery remove rule itself could check if subquery will produce max one row > (using relmetadat's getMaxRowCount) and avoid introducing this branch. -- This message was sent by Atlassian JIRA (v7.6.3#76005)