Oracle Forms on a keyless view

I have a view to look at a lot of people whose information is in 2 different tables. Neither table has a key (sorry, I didn’t define the database). When I address the view with an Oracle Form the first person appears in the list but with the Oracle error FRM-40501:unable to reserve record for update or delete. The underlying SQL error is ORA-01445: canot select ROWID from, or sample, a join view without a key-preserved table. I do need the user to be able to update one of the tables in the view. How do I achieve this?