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  1. Hive
  2. HIVE-2992

JOIN + LATERAL VIEW + MAPJOIN fails to return result (seems to stop halfway through and no longer do the final reduce part)

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    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: 0.8.1
    • Fix Version/s: 0.9.0
    • Component/s: None
    • Labels:
      None
    • Environment:

      ubuntu - hadoop 0.20.2-cdh3u0 - hive 0.8.1

      Description

      Okay first off; I know JOIN + LATERAL VIEW together isn't working so I moved my JOIN into a subquery and that makes the query work properly

      However when I added a MAPJOIN hint for the JOIN in the subquery it will also stop doing the reducer for the main query!
      This only happens when there's a LATERAL VIEW in there though, if I remove the LATERAL VIEW then the main query still get's a reducer to do grouping

      Here's a gist: https://gist.github.com/2499436 Containing the queries and a PHP script which you can run to execute the test case I'm using, which does;

      • setup a database called hive_mapjoin
      • setup tables
      • load some test data
      • do the selects
        You'll need the https://github.com/rcongiu/Hive-JSON-Serde/downloads json-serde-1.1-jar-with-dependencies.jar with it though and change the path
        I guess looking at the queries you guys can probally figure out a better testcase, but maybe it's helpful

      Not sure if this is a bug or me doing something that just isn't supposed to be working, but I can't seem to find any pointers that this wouldn't be supported...

      Here's another gist with the plan.xml: https://gist.github.com/2499658

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            • Assignee:
              Unassigned
              Reporter:
              ruben.devries Ruben de Vries
            • Votes:
              1 Vote for this issue
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              4 Start watching this issue

              Dates

              • Created:
                Updated:
                Resolved: