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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "Hive/HBaseIntegration" by JohnSichi
Date Fri, 05 Mar 2010 00:03:33 GMT
Dear Wiki user,

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

The "Hive/HBaseIntegration" page has been changed by JohnSichi.
http://wiki.apache.org/hadoop/Hive/HBaseIntegration?action=diff&rev1=14&rev2=15

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   * if no column-name is given, then the Hive column will map to all columns in the corresponding
HBase column family, and the Hive MAP datatype must be used to allow access to these (possibly
sparse) columns
   * there is currently no way to access the HBase timestamp attribute, and queries always
access data with the latest timestamp.
   * since HBase does not associate datatype information with columns, the serde converts
everything to string representation before storing it in HBase; there is currently no way
to plug in a custom serde per column
+  * it is not necessary to reference every HBase column family, but those that are not mapped
will be inaccessible via the Hive table; it's possible to map multiple Hive tables to the
same HBase table
  
  The next few sections provide detailed examples of the kinds of column mappings currently
possible.
  

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