Xuefu Zhang created HIVE-7527:
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             Summary: Support order by and sort by on Spark
                 Key: HIVE-7527
                 URL: https://issues.apache.org/jira/browse/HIVE-7527
             Project: Hive
          Issue Type: Sub-task
          Components: Spark
            Reporter: Xuefu Zhang


Currently Hive depends completely on MapReduce's sorting as part of shuffling 
to achieve order by (global sort, one reducer) and sort by (local sort).
Spark has a sort by transformation in different variations that can used to 
support Hive's order by and sort by. However, we still need to evaluate weather 
Spark's sortBy can achieve the same functionality inherited from MapReduce's 
shuffle sort.

Currently Hive on Spark should be able to run simple sort by or order by, by 
changing the currently partitionBy to sortby. This is the way to verify 
theories. Complete solution will not be available until we have complete 
SparkPlanGenerator.



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