See SET SESSION FUNCTION TRACE and Teradata Vantage™ - SQL Data Definition Language Detailed Topics, B035-1184 for information about enabling function traceback.
See CREATE TABLE in Teradata Vantage™ - SQL Data Definition Language Detailed Topics, B035-1184 for general information about global temporary tables and Teradata Vantage™ - SQL External Routine Programming, B035-1147 for information about coding external functions.