Answer all parts of this question.

Read the following case study.

Lakeland Airways Ticketing Case Study (Part 1)

Lakeland Airways issue tickets for travel on their aircraft flights.  A ticket has been defined as a class in the airline’s reservation system and contains the following attributes:

1. TICKET  (ticket-number, passenger-name, issue-date, booking-reference, (from-code, from-airport, to-code, to-airport, date-of-travel, flight-number, departure-time))

2. Two sample tickets are shown below. A ticket can have up to 4 journey legs; where a leg is not used, the words VOID are printed.

3. Normally flights with the same flight number depart and arrive at the same airports and at the same times (e.g. flight LA701 will always travel from Manchester to Gatwick).  Occasionally however the departure time of a given flight number may vary, e.g. LA757 on the tickets below departs one hour earlier on 24/1/2003.

End of case study (Part 1)

a.  Using part 1 of the case study, draw a functional dependency diagram for a Lakeland Airways ticket.  Explain the significance of the 3rd point above- the fact that a flight happens to leave at different times on some dates.

 (10 marks)

b.  Convert the TICKET class into first normal form, second normal form and third normal form.  (You must show each intermediate normal form, although if a class is the same you only need to state this and not show the class definition in full.)

(10 marks)

Read the following extension to the case study.

Lakeland Airways Ticketing Case Study (Part 2)

Lakeland Airways are introducing automatic check-in machines which will use tickets with a magnetic encoding of the ticket details on the reverse of the ticket.  When a machine detects that a ticket has been inserted, the system will read the ticket details and validate them against a database of tickets issued.  If the ticket is valid, the system will consult a seating plan for the appropriate flight and allocate a seat.  If the ticket is invalid or there are no seats left on the flight (because of overbooking), the system will display a message telling the passenger to refer to a member of the airline’s staff.  If a seat is assigned, the passenger will be asked whether they wish to confirm the seat or change the seat.  After confirmation or a change of seat, a boarding pass is printed.

End of case study (Part 2)

c.  A data flow diagram showing the data flows and main processes for part 2 of the case study is shown on the attached template.  A process called Checkin-Control will be used to ensure that processes are executed in the correct sequence.

Using the template provided, complete the data flow diagram showing the necessary control flows. 

Also draw a state-transition diagram detailing the logic of the Checkin-Control process.   

Ensure that you label all the return control flows in the data flow diagram and that they are consistent with the names of transitions in the state-transition diagram.  Inconsistent diagrams will lead to the loss of marks.

(15 marks for the DFD and 15 marks for the STD)

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