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Consider the following relational database for Grand Travel Airlines.
Grand Travel Airlines has to keep track of its flight and airplane history. A flight is uniquely identified by the combination of a flight number and a date. Every passenger who has flown on Grand Travel has a unique passenger number. For a particular passenger who has taken a particular flight, the company wants to keep track of the fare that she paid for it and the date that she made the reservation for it. Clearly, a passenger may have taken many flights (he must have taken at least one to be in the database) and every flight has had many passengers on it.
A pilot is identified by a unique pilot (or employee) number. A flight on a particular date has exactly one pilot. Each pilot has typically flown many flights but a pilot may be new to the company, is in training, and has not flown any flights, yet. Each airplane has a unique serial number. A flight on a particular date used one airplane. Each airplane has flown on many flights and dates, but a new airplane may not have been used at all, yet.
Grand Travel also wants to maintain data about its airplanes' maintenance history; each maintenance procedure has a unique procedure number. A maintenance location has a unique location name. Grand Travel wants to keep track of which airplane had which maintenance procedure performed at which location. For each such event it wants to know the date of the event and the duration.
PILOT Relation
FLIGHT Relation
PASSENGER Relation
RESERVATION Relation
AIRPLANE Relation
MAINTENANCE PROCEDURE Relation
MAINTENANCE LOCATION Relation
SERVICE Relation
a. Identify the candidate keys of each relation.
b. Identify the primary key and any alternate keys of each relation.
c. How many foreign keys does each relation have?
d. Identify the foreign keys of each relation.
e. Indicate any instances in which a foreign key serves as part of the primary key of the relation in which it is a foreign key. Why does each of those relations require a multi-attribute primary key?
f. Identify the relations that support many-to-many relationships, the primary keys of those relations, and any intersection data.
g. Using the informal relational command language described in this chapter, write commands to:
i. Retrieve the record for airplane number 36325.
ii. Retrieve the record for the pilot named Sarah Johnson who was born on 5/22/1959.
iii. List all of the airplanes manufactured by Boeing.
iv. List the airplane number and passenger capacity of every airplane manufactured by Boeing in 1997 .
v. List the airplane number, model, and manufacturer of every airplane.
vi. What company manufactured airplane number 53489?
vii. What was the name and date of birth of the pilot of flight number 182 on 10/30/2003?
viii. List the airplane number, model, and manufacturer of every airplane that was used on flight 118 in 2003.
Direct Quotes
The exchange rate for foreign currencies quoted in units of the domestic currency per one unit of the foreign currency.
Direct Quote
A representation of the amount of foreign currency required to buy or sell one unit of the domestic currency in the foreign exchange markets.
Country C's Currency
The legal tender issued by a sovereign government or central authority of country C.
Country D's Currency
The official currency issued and used for financial transactions in Country D.
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