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The "Hive/LanguageManual/DDL" page has been changed by PhiloVivero.
The comment on this change is: Broken partition_spec example caused me days of 
grief. Trying to make sure no-one else has to suffer this pain..
http://wiki.apache.org/hadoop/Hive/LanguageManual/DDL?action=diff&rev1=88&rev2=89

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  }}}
  You can use ALTER TABLE ADD PARTITION to add partitions to a table.  
Partition values should be quoted only if they are strings. The location must 
be a directory inside of which data files reside.
  
+ Note that it is proper syntax to have multiple partition_spec in a single 
ALTER TABLE, but if you do this in version 0.7, your partitioning scheme will 
fail. That is, every query specifying a partition will always use only the 
first partition. Instead, you should use the following form if you want to add 
many partitions:
+ 
+ {{{
+ ALTER TABLE table_name ADD PARTITION (partCol = 'value1') location 'loc1';
+ ALTER TABLE table_name ADD PARTITION (partCol = 'value2') location 'loc2';
+ ...
+ ALTER TABLE table_name ADD PARTITION (partCol = 'valueN') location 'locN';
+ }}}
+ 
+ Specifically, the following example (which was the default example before) 
will FAIL silently and without error, and all queries will go only to 
dt='2008-08-08' partition, no matter which partition you specify.
+ 
  {{{
  ALTER TABLE page_view ADD PARTITION (dt='2008-08-08', country='us') location 
'/path/to/us/part080808' PARTITION (dt='2008-08-09', country='us') location 
'/path/to/us/part080809';
  }}}
+ 
  An error is thrown if the partition_spec for the table already exists. You 
can use IF NOT EXISTS to skip the error.
  
  === Drop Partitions ===

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