Unit 4 Section 7
Student worksheet
7.1: Analysis scenario worksheet
Below are three scenarios for systems that require computerisation. Read the scenarios
carefully and complete the task for each of them.
Task
You need to produce:
a)
b)
c)
d)
a set of objectives
a data flow diagram
an analysis data dictionary
an E-R diagram.
Scenario 1: That’s Rentertainment
That’s Rentertainment is a new business that rents DVDs to members from a small shop. You
have been asked to create a computer application, using a file-based programmed application
or a database, to replace the current manual record-keeping system. There will be only one
stand-alone workstation with a printer attached. These are kept in the shop.
The current way of working at That’s Rentertainment is as follows:
When a member comes into the shop for the first time, the following information is recorded
on a card: member’s name, address, telephone number, date joined, DVD rented, date rented
and date due to be returned. Each time that member rents another DVD the name of the
DVD, the date rented and the date due to be returned are added to the card. There is also a
space to write in the date the DVD is returned and make a comment; for example, if the
member has been given a special discount, or a DVD was returned late. When a card
becomes full, a new card is stapled to the original one. These cards are filed in member
number order. When members come to the shop, they do not always remember their
membership number and a member of staff has to search for their card by their name, or part
of their address. There are about 3,000 members.
That’s Rentertainment get the DVDs from one supplier only. This supplier sends an up-todate supplier price list once a month. That’s Rentertainment then works out a weekly rental
cost for each DVD each time one is rented. Some members are allowed a 10 per cent
discount. At present, That’s Rentertainment does not keep a record of who these are because
the manager can remember them. However, a computerised system would have to keep a
record of this. There are about 1,000 DVDs and That’s Rentertainment can have up to ten
copies of each DVD. Members often ask for DVDs if they cannot find them on the shelves.
They may ask for any DVD by title, certificate, or category. It often takes some time for staff
to find out this information and the manager would like the computer searches to find
information quickly. The manager is also having trouble keeping track of how many DVDs
he has in stock at any one time as this is not recorded. In addition, the manager would like to
see which are the most and least popular videos rented.
Once a week, the manager goes through the members’ cards and pulls out cards for members
with overdue DVDs. These members are then sent a standard letter reminding them that the
DVD they have rented is overdue. The manager calculates the fine owed, which increases
each week, and writes this on the letter. Occasionally, the manager sends letters to all
members informing them of new releases.
AQA Computing A2 © Nelson Thornes Ltd 2009
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Unit 4 Section 7
Student worksheet
Scenario 2: Interactive teaching aid for binary trees
The Sandon School is a secondary school in Chelmsford, Essex with about 1,200 pupils. It is
a Maths and Computing College with an ICT department that teaches GCSE ICT at Key
Stage 4 and Computing at Key Stage 5.
The computing teacher, Miss Baker, would like an interactive tool to demonstrate the
creation and maintenance of a binary tree, including the adding and deleting of nodes and a
teaching aid simulation for in-order, pre-order and post-order traversal.
Scenario 3: Floor turtle controller
The Sandon School is a secondary school in Chelmsford, Essex with about 1,200 pupils. Mr
Pleasance, the technology teacher, needs a controller for a floor turtle that students have built
for a Key Stage 4 project. The turtle has the ability to move forwards, backwards, left, right,
and circle. Forwards and backwards have a variable distance to indicate the distance to travel
in centimetres from 1 to 1,000. Right and left have a degree variable, which indicates the
number of degrees to turn from 1 to 360. Circle has two variables: the radius of the circle in
centimetres and the degree of the arc. The students must be able to program a sequence of
instructions to move the turtle through a maze.
AQA Computing A2 © Nelson Thornes Ltd 2009
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