Scenario $1$:

A local veterinary hospital is looking for a replacement for their patient tracking system. When asked to describe their data, they responded as follows.

Clients may have one or more pets.

Clients are identified by their phone number.

Clients are tracked by their name and address.

A pet is owned by a single client only.

A pet is identified by their owner's name and the pet name.

Pets are tracked by their species, breed, sex, and neutering status.

A pet can be treated by several different doctors and$/$or technicians $($staff$).$

Each doctor and technician has an employee number and a name.

A pet may have multiple visits that are tracked by date and reason for visit.