Object Oriented Database Oracle PLSQL

SQL> -- CREATE a Table that References Our Row Objects
SQL>
SQL>
SQL> CREATE OR REPLACE TYPE address_obj as OBJECT(
  2        street VARCHAR2(20),
  3        city VARCHAR2(20),
  4        state CHAR(2),
  5        zip CHAR(5));
  6  /
Type created.
SQL>
SQL> CREATE TABLE address_table OF ADDRESS_OBJ;
Table created.
SQL>
SQL> CREATE TABLE client (name VARCHAR2(20),
  2    address REF address_obj scope is address_table);
Table created.
SQL>
SQL>
SQL> DESC client;
 Name                                                                                                  Null?    Type
 ----------------------------------------------------------------------------------------------------- -------- --------------------------------------------------------------------
 NAME                                                                                                   VARCHAR2(20)
 ADDRESS                                                                                                REF OF ADDRESS_OBJ
SQL>
SQL> drop table client;
Table dropped.
SQL>
SQL> drop table address_table;
Table dropped.
SQL>
SQL>
SQL>