Dropping A Method
There is no DROP METHOD statement that you can use to drop a method body.
Instead, what you must do to drop a method is use the DROP METHOD or DROP SPECIFIC METHOD option of the ALTER TYPE statement (see “ALTER TYPE” on page 148) to drop the method signature from its type definition. This action also drops the external routine for the specified method.
You can also use the REPLACE METHOD statement (see “REPLACE METHOD” on page 845) to replace a method body.