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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "Hive/StatsDev" by Ning Zhang
Date Tue, 05 Oct 2010 16:15:10 GMT
Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Hadoop Wiki" for change notification.

The "Hive/StatsDev" page has been changed by Ning Zhang.
http://wiki.apache.org/hadoop/Hive/StatsDev?action=diff&rev1=60&rev2=61

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

  }}}
  then statistics are gathered for the 4 partitions.
  
- If the user issues the command:
+ For a non-partitioned table, you can issue the command:
  {{{
  ANALYZE TABLE Table1 COMPUTE STATISTICS;
  }}}
- then statistics are gathered for the 4 partitions as well as the table itself.
+ to gather statistics of the table. If Table1 is a partitioned table, you have to specify
partition specifications like above. Otherwise a semantic analyzer exception will be thrown.

  
  The user can view the stored statistics by issuing the [[http://wiki.apache.org/hadoop/Hive/LanguageManual/DDL?highlight=(describe)#Describe_Partition|DESCRIBE]]
command. Statistics are stored in the Parameters array. Suppose the user issues the analyze
command for the whole table Table1, then issues the command:
  {{{

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