shameersss1 opened a new pull request, #4120:
URL: https://github.com/apache/hive/pull/4120

   
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   ### What changes were proposed in this pull request?
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   ### Why are the changes needed?
   When hive.auto.convert.join=true and if the underlying query is trying to 
join a large non-native hive table with a small native hive table, The map join 
is happening in the wrong side i.e on the map task which process the small 
native hive table and it can lead to OOM when the non-native table is really 
large and only few map tasks are spawned to scan the small native hive tables.
   
   
   ### Does this PR introduce _any_ user-facing change?
   No
   
   
   ### How was this patch tested?
   Added Qtest to validate the test scenario and the fix works for the same
   


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