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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "Hive/LanguageManual/Transform" by JeffHammerbacher
Date Fri, 13 Nov 2009 01:27:03 GMT
Dear Wiki user,

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The "Hive/LanguageManual/Transform" page has been changed by JeffHammerbacher.
http://wiki.apache.org/hadoop/Hive/LanguageManual/Transform?action=diff&rev1=12&rev2=13

--------------------------------------------------

  In the syntax, both ''MAP ...'' and ''REDUCE ...'' can be also written as ''SELECT TRANSFORM
( ... )''.  There are actually no difference between these three.
  Hive runs the reduce script in the reduce task (instead of the map task) because of the
''clusterBy''/''distributeBy''/''sortBy'' clause in the inner query.
  
- Please also see [[Hive/LanguageManual/SortBy|Sort By / Cluster By / Distribute By]].
+ Please also see [[Hive/LanguageManual/SortBy|Sort By / Cluster By / Distribute By]] and
Larry Ogrodnek's [http://dev.bizo.com/2009/10/hive-map-reduce-in-java.html|blog post].
  
  {{{
  clusterBy: CLUSTER BY colName (',' colName)*

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