title: error: ORA-01730: invalid number of column names specified
body: <p>Please help. I want to create an object view from the ffl tables but i keep getting the above error and can't find any solution. </p>
  
  <pre><code>create table COPY_BOOK (
    NUM number(4,0), 
    DATE_Purchase date, 
    PRICE number(5,2), 
    LOAN_code varchar2(20) ,
    STATUS varchar2(15) check (STATUS in ('GOOD','DAMAGED')), 
    CONSTRAINT CP_PK primary key (num) ,
    constraint Loan_code_D  check (LOAN_CODE in ('NO', 'LOAN')) 
  );
  
  create or replace type copy_book_t as object(
    num   number(4, 0),
    loan_code   varchar2 (20)
  );
  /
  
  create or replace view Vcopy_book of copy_book_t
  with object oid (num)
  as select cb.num, cb.date_purchase, cb.price, cb.loan_code, cb.status
  from copy_book cb;
  /
  </code></pre>
  
  <p>Is there a problem with the type definition?</p>