Question

Basically, I have a supertype( Person) and subtype (Student). I have to insert into person_objtab a student object. A person object has a REF to Address table and when I’m trying to add new student it gives me ‘missing expression’ error. Here’s the code, any help is highly appreciated!

create type address_objtyp as object (
    Line1 varchar2(30),
    Line2 varchar2(30),
    Line3 varchar2(30),
    Postcode varchar2(10),
    Country varchar2(20)
)
/

create type person_objtyp as object (
    NI varchar2 (20),
    Name varchar2(30),
    Address REF address_objtyp,
    Phone varchar2(30)
)
NOT FINAL
/

CREATE type student_objtyp UNDER person_objtyp (
    Dept_id varchar2(10),
    Course varchar2(10),
    StuYear number,
    Total_credits number
)
/

create table address_objtab of address_objtyp;
create table person_objtab of person_objtyp;

INSERT INTO address_objtab VALUES(
address_objtyp('9',  'Bell', 'Lancashire', ' BB52 4GF', 'the UK')
)
/

This is the statement which fails:

INSERT INTO Person_objtab values 
 (student_objtyp 
     (SELECT  2222, 'Jo', REF(aa), '0161 0450 452', '10', 'Computing', '2', 220 
       FROM address_objtab aa
      WHERE aa.postcode = ' BB52 4GF')
)
/

Answer 1

INSERT INTO person_objtab 
VALUES (student_typ(
        2222,
        'Jo',
        (SELECT REF(b) FROM address_objtab b WHERE line1 = '9 Bell'),
         '01200 233 233',
         10,
         'Computing',
         2,
         220
));