DROP FUNCTION Syntax
This statement drops the user-defined function (UDF) named function_name.
To drop a function, you must have the DELETE privilege for the MariaDB database. This is because DROP FUNCTION removes a row from the mysql.func system table that records the function's name, type, and shared library name.Note
To upgrade the shared library associated with a UDF, issue a DROP FUNCTION statement, upgrade the shared library, and then issue a CREATE FUNCTION statement. If you upgrade the shared library first and then use DROP FUNCTION, the server may crash.
DROP FUNCTION is also used to drop stored functions (see , "DROP PROCEDURE and DROP FUNCTION Syntax").