Erwin? Oracle? or me?

Using Erwin I've establish a relationship between the following entities.

Person >|0---|- Neighborhood >|0----|- City >|0---|- Province

I am trying to make the following statement A person is part of a neighborhood
A neighborhood is in a city
A city is in province (well it is for most Canadians but that's besides the point)

After doing that Erwin will take the primary key attribute of neighborhood, city and Province and make them the foreign key of Person which from there will make these foreign key attributes part of the primary key of person.

I understand why the the primary keys of all these entities are now in the person entity but I do not understand why they are part of its Primary Key.

Does it have to do with the fact that Oracle is my target database? Is Erwin trying to tell me how to uniquely identify a person? Any thoughts? Received on Wed Dec 13 2000 - 08:44:00 CET