A company database needs to store information about its employees (identified by ssn, with salary, phone and title as attributes) and departments (identified by dno, with dname and budget as attributes), given the additional information below. Employees work in at least one department; each department is managed by exactly one employee and we want to know the date the manager started managing the department. An employee may be assigned at most one mentor. A mentor is a manager that gives advice for career development related issues to employees working in any department (the mentees). Not all managers are required to serve as mentors. We want to store information about a mentor-mentee relationship and when it was established . Draw an ER diagram to capture the situation described above.

Make sure you capture as many integrity constraints as possible and explicitly mention those that can not be captured by the ER diagram (if any).

(Use arrowheads and bold lines )

Similar to the added photo, but with Mentors/Managers bold

salary dname phone dno budget Employees Manages Departments Works In Dependent child age