Find primary key with matching foreign key

[oraka6]

I need to find out which primary key doesn't have a matching foreign key in the database. I think it has something to do with the data dictionary.

Anyone has any ideas? Thanks!

[inosov]

select owner, constraint_name
from dba_constraints
where constraint_type = 'P'
and (owner, constraint_name) not in
(select r_owner,r_constraint_name
from dba_constraints
where constraint_type = 'R');

[oraka6]

Thank you!!