This example creates a structured UDT named person from four predefined data types and the structured UDT address, making it a 2-level nested type. The UDT is nested because the type address is a structured UDT having two attributes. In this case, both of those attributes are predefined types, but if one or more of them had been a structured type, person would be a 3-level nested type.
CREATE TYPE SYSUDTLIB.person AS ( ssn CHARACTER(11), first_name VARCHAR(20), middle_name VARCHAR(20), last_name VARCHAR(20), domicile address ) NOT FINAL;