Consider the following information about a university database:

Professors have an SSN, a name, an age, a rank, and a research specialty.

Projects have a project number, a sponsor name (e.g., NSF), a starting date, an

ending date, and a budget.

Graduate students have an SSN, a name, an age, and a degree program (e.g., M.S.

or Ph.D.).

Each project is managed by one professor (known as the project’s principal investigator).

Each project is worked on by one or more professors (known as the project’s

co-investigators).

Professors can manage and/or work on multiple projects.

Each project is worked on by one or more graduate students (known as the

project’s research assistants).

When graduate students work on a project, a professor must supervise their work

on the project. Graduate students can work on multiple projects, in which case

they will have a (potentially different) supervisor for each one.

Departments have a department number, a department name, and a main office.

Departments have a professor (known as the chairman) who runs the department.

Professors work in one or more departments, and for each department that they

work in, a time percentage is associated with their job.

Graduate students have one major department in which they are working on their

degree.

Each graduate student has another, more senior graduate student (known as a

student advisor) who advises him or her on what courses to take.