CREATE Or Replace TYPE ProductType AS OBJECT (
    id    NUMBER,
    make  VARCHAR2(15),
    model VARCHAR2(15)
  ) NOT FINAL NOT INSTANTIABLE;


CREATE Or replace TYPE SubProduct1 UNDER ProductType (
    convertible CHAR(1)
  );

CREATE Or replace TYPE SubProduct2 UNDER ProductType (
    sidecar CHAR(1)
  );

CREATE TABLE product OF ProductType;

CREATE TABLE cars OF SubProduct1;

CREATE TABLE motorcycles OF SubProduct2;

INSERT INTO cars VALUES (
    SubProduct1(1, 'AA', 'MR2', 'Y')
  );

INSERT INTO motorcycles VALUES (
    SubProduct2(1, 'BB', 'V-Rod', 'N')
  );

SELECT *
  FROM cars;

        ID MAKE            MODEL           C
---------- --------------- --------------- -
         1 AA              MR2             Y