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Namit Jain commented on HIVE-3430: ---------------------------------- Consider the following query: select * from ( select c.value, count(1) as cnt from ( select b.key, b.value from (select key, length(value) from T1 where ds = '1') a join T2 b on b.ds = '1' and a.key = b.key ) c group by c.value ) d join (select value, count(1) as cnt from T2 c where c.ds = '1' group by value) e on d.value = e.value; Every join and group by above has a separate map-reduce job. > group by followed by join with the same key should be optimized > --------------------------------------------------------------- > > Key: HIVE-3430 > URL: https://issues.apache.org/jira/browse/HIVE-3430 > Project: Hive > Issue Type: Improvement > Components: Query Processor > Reporter: Namit Jain > -- 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