[ https://issues.apache.org/jira/browse/HIVE-2253?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13161334#comment-13161334 ]
Hudson commented on HIVE-2253: ------------------------------ Integrated in Hive-trunk-h0.21 #1117 (See [https://builds.apache.org/job/Hive-trunk-h0.21/1117/]) HIVE-2253. Merge failing of join tree in exceptional case (Navis Ryu via jvs) jvs : http://svn.apache.org/viewcvs.cgi/?root=Apache-SVN&view=rev&rev=1209226 Files : * /hive/trunk/ql/src/java/org/apache/hadoop/hive/ql/parse/SemanticAnalyzer.java * /hive/trunk/ql/src/test/queries/clientpositive/mergejoins.q * /hive/trunk/ql/src/test/results/clientpositive/mergejoins.q.out > Merge failing of join tree in exceptional case > ---------------------------------------------- > > Key: HIVE-2253 > URL: https://issues.apache.org/jira/browse/HIVE-2253 > Project: Hive > Issue Type: Bug > Components: Query Processor > Affects Versions: 0.9.0 > Environment: hadoop 0.20.2, hive 0.7.0 > Reporter: Navis > Assignee: Navis > Priority: Minor > Fix For: 0.9.0 > > Attachments: HIVE-2253-0.8.0.patch, HIVE-2253.1.patch.txt > > > In some very exceptional cases, SemanticAnayzer fails to merge join tree. > Example is below. > create table a (val1 int, val2 int) > create table b (val1 int, val2 int) > create table c (val1 int, val2 int) > create table d (val1 int, val2 int) > create table e (val1 int, val2 int) > 1. all same(single) join key --> one MR, good > select * from a join b on a.val1=b.val1 join c on a.val1=c.val1 join d on > a.val1=d.val1 join e on a.val1=e.val1 > 2. two join keys --> expected to have two MR, but resulted to three MR > select * from a join b on a.val1=b.val1 join c on a.val1=c.val1 join d on > a.val1=d.val1 join e on a.val2=e.val2 > 3. by changing the join order, we could attain two MR as first-expectation. > select * from a join e on a.val2=e.val2 join c on a.val1=c.val1 join d on > a.val1=d.val1 join b on a.val1=b.val1 -- 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