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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Trivial Update of "Hive/LanguageManual/SortBy" by ZhengShao
Date Thu, 22 Jan 2009 22:54:24 GMT
Dear Wiki user,

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The following page has been changed by ZhengShao:
http://wiki.apache.org/hadoop/Hive/LanguageManual/SortBy

------------------------------------------------------------------------------
  Hive uses the columns in ''SORT BY'' to sort the rows before feeding the rows to a single
reducer.  The sort order will be dependent on the column types.  If the column is of numeric
type, then the sort order is also in numeric order.  If the column is of string type, then
the sort order will be lexicographical order.
  
  
- == Difference between Sort By and Order By ==
+ === Difference between Sort By and Order By ===
  Most database systems supports ''ORDER BY'', which Hive does not support directly.
  Hive supports ''SORT BY'' which sorts the data per reducer.
  
@@ -40, +40 @@

  }}}
  
  
- == How to do Order By? ==
+ === How to do Order By? ===
  
  We can set the number of reducers to 1, to make sure we have the same result as ''ORDER
BY''.
  

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