[ https://issues.apache.org/jira/browse/HIVE-2566?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Phabricator updated HIVE-2566: ------------------------------ Attachment: HIVE-2566.D405.3.patch njain updated the revision "HIVE-2566 [jira] reduce the number map-reduce jobs for union all". Reviewers: JIRA Make union24.q deterministic REVISION DETAIL https://reviews.facebook.net/D405 AFFECTED FILES ql/src/test/results/clientpositive/merge4.q.out ql/src/test/results/clientpositive/auto_join27.q.out ql/src/test/results/clientpositive/union19.q.out ql/src/test/results/clientpositive/union4.q.out ql/src/test/results/clientpositive/union14.q.out ql/src/test/results/clientpositive/create_view.q.out ql/src/test/results/clientpositive/union5.q.out ql/src/test/results/clientpositive/ql_rewrite_gbtoidx.q.out ql/src/test/results/clientpositive/load_dyn_part14.q.out ql/src/test/results/clientpositive/union15.q.out ql/src/test/results/clientpositive/union24.q.out ql/src/test/results/clientpositive/union10.q.out ql/src/test/results/clientpositive/input25.q.out ql/src/test/results/clientpositive/union6.q.out ql/src/test/results/clientpositive/lineage1.q.out ql/src/test/results/clientpositive/union11.q.out ql/src/test/results/clientpositive/join35.q.out ql/src/test/results/clientpositive/union20.q.out ql/src/test/results/clientpositive/input26.q.out ql/src/test/results/clientpositive/union7.q.out ql/src/test/results/clientpositive/union17.q.out ql/src/test/results/clientpositive/union12.q.out ql/src/test/results/clientpositive/stats1.q.out ql/src/test/results/clientpositive/union18.q.out ql/src/test/results/clientpositive/union3.q.out ql/src/test/results/clientpositive/ppd_union_view.q.out ql/src/test/queries/clientpositive/union24.q ql/src/java/org/apache/hadoop/hive/ql/optimizer/GenMRProcContext.java ql/src/java/org/apache/hadoop/hive/ql/optimizer/GenMRUnion1.java ql/src/java/org/apache/hadoop/hive/ql/optimizer/GenMapRedUtils.java ql/src/java/org/apache/hadoop/hive/ql/exec/Operator.java > reduce the number map-reduce jobs for union all > ----------------------------------------------- > > Key: HIVE-2566 > URL: https://issues.apache.org/jira/browse/HIVE-2566 > Project: Hive > Issue Type: Improvement > Reporter: Namit Jain > Assignee: Namit Jain > Attachments: HIVE-2566.D405.1.patch, HIVE-2566.D405.2.patch, > HIVE-2566.D405.3.patch > > > A query like: > select s.key, s.value from ( > select key, value from src2 where key < 10 > union all > select key, value from src3 where key < 10 > union all > select key, value from src4 where key < 10 > union all > select key, count(1) as value from src5 group by key > )s; > should run the last sub-query > 'select key, count(1) as value from src5 group by key' > as a map-reduce job. > And then the union should be a map-only job reading from the first 3 map-only > subqueries > and the output of the last map-reduce job. > The current plan is very inefficient. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira