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From "r7raul1984@163.com" <r7raul1...@163.com>
Subject hive on tez optimize MRR to MR?
Date Wed, 22 Apr 2015 08:45:41 GMT


select userid,count(*) from u_data group by userid order by userid    will product MRR.

I think when the result of  userid,count(*) is small(one reduce can process the result) .
This query plan can optimize to MR ?




r7raul1984@163.com
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