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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 Hive Interactive Shell Commands, including Hive Resources, for more information on how to add/delete files from the Hive classpath. Using this, you can register User Defined Functions (UDF's).
Also see Hive Plugins for general information about creating custom UDFs.
Drop Function
You can unregister a UDF as follows:
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