Keeping Primary Key

[marcoamo]

I did my logical data model using a class diagram to represent the entities and Class relationships to represent the relationships. Now, I am tranforming into a Physical model (DDL option). Questions:
- How I keep the primary key I defined in the Class/logical model (it is been replaced by a system generated attribute (class_nameiId)).
- How can I define a identifiable relationship (where the foreign key will become part of the primary key on the chlid table)?

Thanks.