SQL>
SQL> CREATE OR REPLACE TYPE personType AS OBJECT
2 (person_id VARCHAR2(10),
3 person_name VARCHAR2(30))
4 /
SQL>
SQL> CREATE OR REPLACE TYPE courseType AS OBJECT
2 (course_id VARCHAR2(10),
3 course_name VARCHAR2(30),
4 course_Programmer REF personType)
5 /
Type created.
SQL>
SQL>
SQL>
SQL>
SQL> CREATE TABLE Programmer OF personType
2 (person_id NOT NULL,
3 PRIMARY KEY (person_id));
Table created.
SQL>
SQL>
SQL> CREATE TABLE Course OF courseType
2 (course_id NOT NULL,
3 PRIMARY KEY (course_id));
Table created.
SQL>
SQL>
SQL>
SQL>
SQL> drop type personType force;
Type dropped.
SQL>
SQL>
SQL>
SQL> drop type courseType force;
Type dropped.
SQL>
SQL>
SQL>
SQL> drop table Programmer;
Table dropped.
SQL>
SQL>
SQL> drop table Course;
Table dropped.
SQL>