SQL> desc person
 Name                            Null?    Type
 ------------------------------- -------- ----
 ID                                       NUMBER
 GENDER                                   VARCHAR2(1)
 FIRST_NAME                               VARCHAR2(40)
 LAST_NAME                                VARCHAR2(40)
 BIRTH_DATE                               DATE

SQL>  CREATE TABLE people OF PERSON;

Table created.

SQL> INSERT INTO people
  2  ( id
  3  , gender
  4  , first_name
  5  , last_name
  6  , birth_date )
  7  VALUES
  8  ( 1
  9  , 'M'
 10  , 'Lisa'
 11  , 'Simpson'
 12  , DATE '1994-01-01' );

1 row created.

SQL> INSERT INTO people
  2  ( id
  3  , gender
  4  , first_name
  5  , last_name
  6  , birth_date )
  7  VALUES
  8  ( 2
  9  , 'M'
 10  , 'Bart'
 11  , 'Simpson'
 12  , DATE '1993-01-01' );

1 row created.

SQL> commit;

Commit complete.

SQL> select * from people;

    ID G FIRST_NAME           LAST_NAME            BIRTH_DATE
------ - -------------------- -------------------- -----------
     1 M Lisa                 Simpson              01-JAN-1994
     2 M Bart                 Simpson              01-JAN-1993

2 rows selected.

<b>SQL> UPDATE people p SET p = PERSON(1, 'F', 'Lisa', 'Simpson', DATE '1994-01-01') WHERE id = 1;</b>

1 row updated.

SQL> select * from people;

   ID G FIRST_NAME           LAST_NAME            BIRTH_DATE
----- - -------------------- -------------------- -----------
    1 F Lisa                 Simpson              01-JAN-1994
    2 M Bart                 Simpson              01-JAN-1993

2 rows selected.

-- Try the same syntax on an ordinary (non-object) table:

SQL> create table regular_table as select * from people;

Table created.

SQL> UPDATE regular_table p SET p = PERSON(1, 'F', 'Lisa', 'Simpson', DATE '1994-01-01') WHERE id = 1;
UPDATE regular_table p SET p = PERSON(1, 'F', 'Lisa', 'Simpson', DATE '1994-01-01') WHERE id = 1
                           *
ERROR at line 1:
ORA-00904: "P": invalid identifier

SQL>