Database Concepts
Develop an EER model for the following situation using the traditional EER notation, the Visio notation or the supertypes notation.
An international school of technology has hired you to create a database management system to assist in scheduling classes. After several interviews with the president, you have come up with the following list of entities, attributes, and initial business rules:
- Room is identified by Building_1D and Room_NO and also has a Capacity. A room can be either a lab or a classroom. If it is a classroom, it has an additional attribute called Board_Type.
- Media is identified by Mtypeid and has attributes of MediaType and TypeDescription. Note: Here we are tracking type of media (such as VCR, projector, etc.) not the individual piece of equipment. Tracking of equipment is outside the scope of this project.
- Computer is identified by Ctypeid and has attributes ComputerType, TypeDescription, DiskCapacity, and ProcessorSpeed. Please note: As with Media Type, we are tracking only the type of computer, not an individual computer. You can think of this as a class of computers (e.g., PIII 900MHZ).
- Instructor has an identifier Emp_ID and has attributes Name, Rank, and Office Phone,
- Timeslot has identifier TSIS and has attributes DayofWeek, StartTime, and EndTime.
- Course has identifier CourseID and has attributes CourseDescription and Credits. Course can have one, none or many prerequisites. Courses also have one or more sections.
- Section has identifier SectionID and attribute EnrollmentLimit
After further discussions, you have come up with some additional business rules to help you create the initial design:
- An instructor teaches one, none or many sections of a course in a given semester.
- An instructor specifies preferred time slots
- Scheduling data are kept for each semester, uniquely identified by semester and year.
- A room can be scheduled for one section or no section during one time slot in a given semester of a given year. However, one room can participate in many schedules, one schedule, or no schedules; one time slot can participate in many schedules, one schedule, or no schedules; one section can participate in many schedules, one schedule or no schedule. Hint: Can you associate this to anything that you have seen before.
- A room can have one type of media, several types of media, or no media.
- Instructors are trained to use one, none, or many types of media
- A lab has one or more computer types. However, a classroom does not have any computers.
- A room cannot be both a classroom and a lab. There also are no other room types to be incorporated into the system.