I am adding a non-identifying relationship between two entities. Toad DM adds the foreign key attribute to the child table. But, since the entity was reverse-engineered, it already has that attribute. If I edit the entity, I see that the attribute is duplicated. Could it not add the duplicate? I'm trying to turn off the generation of foreign keys on other entities. It seems that everytime I identify a primary key on an entity, any entity it relates to becomes a foreign key automatically on the other entities it relates to. I want to turn that off. I can't find where to turn it off.
The relationship without generating foreign keys on other related entities is not possible. Also, there's no way to turn it off. Nevertheless, if it happened that you already had an attribute in a child entity and that the FK had been compounded. Use the Foreing Keys Mapping feature.
Have a look at the Help File | Entity Relationship diagram | Foreign keys mapping for more detail.