Assume that a planet called Zion exists. In Zion, NEXUS is an inter-galactic enterprise that leases spacecraft to aliens for a fee. All spacecraft owned by NEXUS can be used for daily rental or contract based rental. Aliens can be classified as Warlord or Explorer. The data for all aliens are stored for recording purposes. Each spacecraft is fully equipped at the time it is rented out. However, an alien can request for additional equipment to be installed. Such equipment includes zap-gun, protective shield, time warp etc. NEXUS also provides pilot service upon request. Each pilot is employed on a part-time basis. Each spacecraft has a contract with the maintenance space dock. Every maintenance activity is recorded. Activities include changing of plutonium energy pack, change of radar guidance system, and any replacement of parts. All history of maintenances is kept as accurate maintenance records.
Propose a database system for NEXUS based on the scenario given.
SCENARIO 2
Propose a database system for a travel agency. In this travel agency, there are three types of employees: Counter staff, Executive and Managers. An executive and a Counter Staff may report to many managers, and at the same time some managers are not assigned to oversee any executive or counter staff. The workflow in this company is simple. A customer will place a booking with an executive. Each Executive deals with more than one customer. Payment is made by the customer to the counter. Each counter has one staff stationed there. Each counter can serve one customer at a time.
SCENARIO 3
The Gaya Motor Vehicle Company manufactures a high volume of prestige passenger motor vehicles. GMVC relies on a number of suppliers to supply many components, which are assembled into vehicles. A supplier may supply at most 10 different components. It is important to maintain information about the supplier such as name, address, and contact person. Each vehicle has its own model name and