Apple WebObjects 3.5 - Manual (Page 72)

Chapter 3 Creating a WebObjects Database Application
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1. Select movieId as the primary key for the Movie entity.
2. Click Next.
3. Select both movieId and talentId as the primary key for the MovieRole entity.
MovieRole’s primary key is compound; that is, it’s composed of more than
one attribute. Use a compound primary key when any single attribute isn’t
sufficient to uniquely identify a row. For MovieRole, the combination of
the
movieId and talentId attributes is guaranteed to uniquely identify a row.
4. Click Next.
5. Select talentId as the primary key for the Talent entity.
6. Click Next.
Specifying Referential Integrity Rules
If you’re using a database that stores foreign key definitions in its database
server’s schema information, the wizard reads them and creates corresponding
relationships in your model. For example, Movie has a to-many relationship to
MovieRole (that is, a Movie has a vector of MovieRoles), and Talent has a
to-many relationship to MovieRole. The wizard now asks you to provide
additional information about the relationships so it can further configure them.
Shift-click to select more
than one attribute.