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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "Hive/LanguageManual/DDL" by JohnSichi
Date Wed, 30 Dec 2009 02:09:25 GMT
Dear Wiki user,

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

The "Hive/LanguageManual/DDL" page has been changed by JohnSichi.
http://wiki.apache.org/hadoop/Hive/LanguageManual/DDL?action=diff&rev1=37&rev2=38

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

  
  NOTE: These commands will only modify Hive's metadata, and will NOT reorganize or reformat
existing data. Users should make sure the actual data layout conforms with the metadata definition.
  
+ === Create Function ===
+ {{{
+ CREATE TEMPORARY FUNCTION function_name AS class_name
+ }}}
+ This statement lets you create a function that is implemented by the class_name. You can
use this function in Hive queries as long as the session lasts. You can use any class that
is in the class path of Hive. You can add jars to class path by executing 'ADD FILES' statements.
Please refer to the CLI section in the User Guide for more information on how to add/delete
files from the Hive classpath. Using this, you can register User Defined Functions (UDF's).
+ 
+ === Drop Function ===
+ 
+ You can unregister a UDF as follows:
+ 
+ {{{
+ DROP TEMPORARY FUNCTION function_name
+ }}}
+ 
  == Show/Describe Statements ==
  These statements provide a way to query the Hive metastore for existing data and metadata
accessible to this Hive system.
  
@@ -291, +305 @@

  }}}
  This statement lists metadata for a given partition. The output is similar to that of DESCRIBE
TABLE. Presently, the column information is not used while preparing plans.
  
- === Create Function ===
- {{{
- CREATE TEMPORARY FUNCTION function_name AS class_name
- }}}
- This statement lets you create a function that is implemented by the class_name. You can
use this function in Hive queries as long as the session lasts. You can use any class that
is in the class path of Hive. You can add jars to class path by executing 'ADD FILES' statements.
Please refer to the CLI section in the User Guide for more information on how to add/delete
files from the Hive classpath. Using this, you can install User Defined Functions.
- 

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