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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "Hive/LanguageManual/DDL/BucketedTables" by PaulYang
Date Wed, 14 Jul 2010 22:21:19 GMT
Dear Wiki user,

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The "Hive/LanguageManual/DDL/BucketedTables" page has been changed by PaulYang.
http://wiki.apache.org/hadoop/Hive/LanguageManual/DDL/BucketedTables?action=diff&rev1=9&rev2=10

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- This is a brief example on creating a populating bucketed tables.  Bucketed tables are fantastic
in that they allow much more efficient sampling than do non-bucketed tables, and they may
later allow for time saving operations such as mapside joins.  However, the bucketing specified
at table creation is not enforced when the table is written to, and so it is possible for
the table's metadata to advertise properties which are not upheld by the table's actual layout.
 This should obviously be avoided.  Here's how to do it right.
+ This is a brief example on creating and populating bucketed tables.  Bucketed tables are
fantastic in that they allow much more efficient sampling than do non-bucketed tables, and
they may later allow for time saving operations such as mapside joins.  However, the bucketing
specified at table creation is not enforced when the table is written to, and so it is possible
for the table's metadata to advertise properties which are not upheld by the table's actual
layout.  This should obviously be avoided.  Here's how to do it right.
  
  First there’s table creation:
  {{{

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