This is the documentation for Cloudera Impala 2.0.x.
Documentation for other versions is available at Cloudera.com.

DROP FUNCTION Statement

Removes a user-defined function (UDF), so that it is not available for execution during Impala SELECT or INSERT operations.

Syntax:

DROP [AGGREGATE] FUNCTION [IF EXISTS] [db_name.]function_name(type[, type...])

Statement type: DDL

Usage notes:

Because the same function name could be overloaded with different argument signatures, you specify the argument types to identify the exact function to drop.

Restrictions:

Currently, Impala UDFs and UDAs written in C++ are not persisted in the metastore database. Information about these functions is held in the memory of the catalogd daemon. You must reload them by running the CREATE FUNCTION statements again each time you restart the catalogd daemon. This limitation does not apply to Impala UDFs and UDAs written in Java.

Cancellation: Cannot be cancelled.

User-Defined Functions (UDFs), CREATE FUNCTION Statement