Reference column with user-defined type in select statement : col « System Tables Data Dictionary « Oracle PL/SQL Tutorial

1. Oracle PL/SQL Tutorial
2. System Tables Data Dictionary
3. col

SQL>
SQL>
SQL> create or replace type address_type as object
  2    ( city    varchar2(30),
  3      street  varchar2(30),
  4      state   varchar2(2),
  5      zip     number
  6    )
  7  /

Type created.

SQL> create or replace type person_type as object
  2    ( name             varchar2(30),
  3      dob              date,
  4      home_address     address_type,
  5      work_address     address_type
  6    )
  7  /

Type created.

SQL> create table people of person_type
  2  /

Table created.

SQL> insert into people values ( 'Tom', '15-mar-1965',
  2    address_type( 'R', '1 Street', 'Va', '45678' ),
  3    address_type( 'R', '1 Way', 'Ca', '23456' ) );

1 row created.

SQL> /

1 row created.

SQL>
SQL> select name, p.home_address.city from people p;

NAME                           HOME_ADDRESS.CITY
------------------------------ ------------------------------
Tom                            R
Tom                            R

SQL>
SQL> drop table people;

Table dropped.

SQL>
SQL> drop type person_type;

Type dropped.

SQL> drop type address_type;

Type dropped.