THE CASE FOR QUESTION 1
The Red Star Case (RSC) is “Car Phone Holder” manufacturing company that has three factories in different cities.
These factories are responsible for and making different Car Phone Holders. A specific Phone Holder manufacturing process (for example, Car Phone Holder for Toyota Corolla) is always under the control of just one factory.
RSC Employees work in three manufacturing factories and each employee works in only one factory. The employee lives in the same city. Every local manufacturing factory is managed by an employee who works in the same plant; but every employee is not a factory manager, nor can an employee manage more than one site. Each and every local factory must have a manager. Some employees are assigned to work on projects (different Car Phone Holder) and in some cases might even be assigned to work on several projects simultaneously. Some of the employees also supervise other employees but all employees need not be supervised – the employees that are supervised, are supervised by just one employee.
QUESTION 1: Develop the Presentation Layer ER Diagram for RSC case. Draw a Chen’s notation ER diagram that shows the entity types and relationship types. You can use DRAW.io
THE CASE FOR QUESTIONS 2,3, and 4
Yu are given ER Diagram for Airports database. Assume that data are maintained on airports around the country for a company that offers a flight chartering service for college teams. They gather information from a wide variety of sources, but have had considerable difficulty in the past obtaining data on runway surfaces at airports located in small college towns. Company pilots need access to this information when they must land either at airports such as these or in occasional emergencies, when they must land at other small airports that are not located in college towns.
As a result, as shown here, they have created a RUNWAY_SURFACE entity type separate from a RUNWAY entity type.
Answers the questions below
Question 2: Identify each entity, primary key(s) and (if there is) the foreign key (s)
Question 3 : Explain the relationship among the entities
Question 4 : What is the purpose of having RUNWAY_SURFACE entity