DROP TYPE <type_name> AS <type>;
Removes a type alias from KSQL. This statement doesn't fail if the type is in use in active queries or user-defined functions, because the DROP TYPE statement doesn't track whether queries are using the type. This means that you can drop a type any time, and old queries continue to work. Also, old queries running with a dropped type and don't change if you register a new type with the same name.
DROP TYPE ADDRESS;