1. Database Design & Implementation Workshop 4 - Drawing ER Diagrams Possible Answers for Exercise 1 StaffDepartment M Work in => <= Has 1 a) A member of staff MUST work in a department, and there are many members of staff in each department.

2. bus garage bus/route route Has => <= Park in Covers => Has => 1 M M M 1 1 b)Several buses can park in the garage, and each bus may cover any number of routes.

3. c) Each producer is in charge of several plays and there are several actors appearing in each play. At any one time and an actor may be involved in more than one play. Actor Play Producer 1 M M M in charge of => <= produced by Play/Act 11 involves => appears in =>

4. Operator Operator/Machine Machine Department Belong to Has Work on M M I I M I d)An operator can work on many machines and each machine has many operators. Each machine belongs to one department, but a department can have many machines.