DatabaseSpy supports user-defined functions and displays them in a separate folder on the schema/database level. For each function, a Parameters sub-folder is provided where the function's parameters and their data types are listed.
Functions can be added to the favorites. Some maintenance options applicable to functions are available through the context menu (see Generating SQL Statements). Please note that functions are not supported in Access databases.
Be sure to always add the schema prefix to the function name when you select a function.