Ask a database administrator or database or system analyst in a local company to show you an EER (or E-R) diagram for one of the organization's primary databases.
Does this organization model have supertype/subtype relationships? If so, what notation is used, and does the CASE tool the company uses support these relationships? Also, what types of business rules are included during the EER modeling phase? How are business rules represented, and how and where are they stored?