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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Trivial Update of "Hive/LanguageManual/SortBy" by bryanxu
Date Mon, 28 Jun 2010 07:14:39 GMT
Dear Wiki user,

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The "Hive/LanguageManual/SortBy" page has been changed by bryanxu.
http://wiki.apache.org/hadoop/Hive/LanguageManual/SortBy?action=diff&rev1=6&rev2=7

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  === Difference between Sort By and Order By ===
- Hive supports ''SORT BY'' which sorts the data per reducer. The difference between "order
by" and "sort by" is that the former guarantees total order in the output while the latter
only guarantees ordering of the rows withint a reducer. If there are more than one reducer,
"sort by" may give partially ordered final results. 
+ Hive supports ''SORT BY'' which sorts the data per reducer. The difference between "order
by" and "sort by" is that the former guarantees total order in the output while the latter
only guarantees ordering of the rows within a reducer. If there are more than one reducer,
"sort by" may give partially ordered final results. 
  
  Basically, the data in each reducer will be sorted according to the order that the user
specified.  The following example shows 
  

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