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Guidance on the coursework (Paper 2) Getting started Introduction

The coursework project is designed to allow you to demonstrate that you have the techniques and skills to solve a computing problem. In particular, it will be used to assess the three skills: • knowledge and understanding • problem-solving and realisation • communication. You must undertake and document a project, which involves using a computer to solve a significant information processing problem of your choice. If you write a thorough report on your work, it is likely to be one of the longest pieces of documentation you have ever produced, although its quality is as important as its size. It will be an achievement of which you can justly be proud. It will help to have a copy of the relevant parts of the syllabus, especially the assessment criteria. If your teacher has not already provided you with a copy, you can find the syllabus for the year in which you will submit your coursework by following the instructions at the beginning of the document ‘Learning and revision guide’ on this Student’s CD-ROM. The ‘Assessment criteria for coursework’ occupy several pages towards the end of the syllabus. You will need to demonstrate that you can perform a number of tasks, including: • defining your problem clearly, including a clear description of the business or organisation • choosing an appropriate method of solution, including: – breaking it down into sub-problems – writing and drawing detailed designs for input, processing, storage and output – choosing suitable hardware – choosing whether software should be a customised off-the-shelf item or purpose-built • building, describing and testing your solution • writing appropriate documentation for the user (user guide), including – general information about the problem and solution – how to use the new system • writing appropriate technical documentation, including – technical explanation and justification of the design – information to allow maintenance and development of the system • evaluating your solution and suggesting improvements. Your teacher will award marks for your written work, with the following maximum marks: Analysis Design Implementation (Building) Testing Documentation Evaluation Total

Cambridge IGCSE Computer Studies

11 14 8 7 5 5 50

marks marks marks marks marks marks marks

© Cambridge University Press 2011

Guidance on the coursework (Paper 2)

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Notice that 25 out of 50 (that is 50%) of the marks are available for Analysis and Design before you even build the solution; this emphasises the importance of these sections and the level of detail required. Perfection is not required in the ‘Implementation’ section to score high marks; you simply need thorough written work and sufficient testable input, processing, storage and output. A few of the trickier parts not working perfectly may only cause you to lose 1 mark! Selecting the problem

Think of the information processing problem that you choose as a challenge. It will involve finding a solution to the requirements of a business, organisation or an individual. It has to be sufficiently complex that you can write a detailed report but not so complicated that you cannot solve it. If your problem can be solved in a single step, it is probably not complicated enough. To get maximum marks, the syllabus requires you to tackle a problem of a ‘complex’ nature. This means that you should: • use some of the more advanced facilities of a single application package, or • use two generic application packages such as a word processing application to produce a mail merge using a data source managed by a database management application, or • write a program for the purpose, using modules and file handling. You can choose to solve your problem by using an existing software applications package or by writing your own program. If you choose to use existing software applications, you need to have good knowledge of how they work and how they can be used. If you choose to write your own program, you need some knowledge and experience of a computer programming language. You might find it daunting to seek out your own suitable problem to solve. If you have a strong hobby or business interest, it may pose a suitable challenge. If not, try not to invent an imaginary user because this might not lead to a challenging problem. Instead, try talking to someone you know well who is, perhaps, older than you, with experience of good ways of dealing with everyday business, domestic or social record-keeping or accounting transactions. Such a person might be able to provide you with a realistic problem. For example, talk to a parent, teacher or friend about their real or simulated needs: • in the workplace, which could relate to the business or even subscriptions to a workers’ night out • at home, for example keeping track of household income and expenditure • managing aspects of a club such as participation or subscriptions • managing a private hobby activity, which could be anything from cataloguing a collection of everyday objects, such as seashells, plants, feathers, postage stamps, beer mats or CDs to an inventory of the contents of a valuable collection for insurance purposes. The problem can involve a manual, paper-based system that would benefit from computerisation, or a limited computerised system that needs improvement or extension. Remember that a system that is disorganised and runs on notes jotted on scraps of paper is still a sort of solution for someone’s problem. It has problems associated with it that you will be able to describe. Your teacher might ask you to submit a written proposal for your project or even a brief feasibility study, in which you explain how well your skills and the available resources match the demands of your proposed problem and are likely to produce a good solution. Your teacher will be able to offer you guidance, as they know your strengths and weaknesses.




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Often, the mark you are able to score in your coursework project is closely linked to your choice of problem to be solved. The project involves using a computer to solve a substantial problem, testing your solution on a computer system and thoroughly documenting it because you only receive marks for your written report. Some topics and the associated method of solution might make it difficult to score marks and satisfy some of the assessment criteria. So, make sure that your project involves the use of a computer to produce a solution to a problem. Projects that are a purely theoretical description of some aspect of a problem, that is solved using a word processor, will score relatively low marks, unless you include your own macros and are able to fully document the use of those macros. It is essential that the project attempts to solve a particular problem and the solution produces some actual output. When choosing your problem to solve, you may wish to look at the marks available in each section and the assessment criteria, to see whether your proposed problem will allow you to score marks in each section. If your problem and/or chosen method of solution is unable to meet a significant number of assessment criteria then perhaps you should reconsider your choice of problem. You should note that not every project will be capable of scoring marks in every section. For example if you choose a problem for which there is no existing solution then it automatically follows that you cannot score marks for the ‘description of the existing solution’ and the ‘evaluation of the existing solution’. Therefore a total of 4 marks out of 50 are immediately unavailable. We hope you will use this information to ensure that the problem you choose for your project is suitable and offers an opportunity for further possible extension. The following list is offered as a suggestion of possible problems to solve, but it is in no way a complete list and you are encouraged to think of your own problem: • an inventory/stock control system • airline/theatre reservation system • cruise/holiday booking system • real estate agency • website creation • computer-controlled greenhouse, lift, traffic lights/sensors • payroll/wages • doctor/dentist surgeries, hospital records • sports club/library. Choice of hardware and software

While you are still choosing a problem for your project, you are advised to check precisely what hardware and software are available at school or from elsewhere. You also need to think realistically about your skill level with the available types of software and programming language. This will also help you to select the most suitable method of solution at the end of the Analysis stage. Hardware

For example, there is no point getting excited about developing a solution for a document processing problem that involves a barcode scanner if your school does not have one and you cannot get access to one. You will need to pay particular attention to peripheral devices and note the strengths and weaknesses of each particular device. This will help you to select appropriate input, storage and output devices for your problem and justify your choices later.




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Most problems use the keyboard as the primary input device. However, as a possible enhancement to the solution you might wish to suggest using an alternative input method such as a document reader. As you probably do not have one available, you could state that you will simulate one with a scanner and optical character recognition (OCR) software. Alternatively, you might consider using a touchscreen. Again, you could state that you will simulate one with a normal mouse and display screen. You would simply design suitable menus, using command buttons or drawing objects to which you can assign macros or hyperlinks, and each click with a mouse would simulate a touch with a finger. Software

You also need to be sure what software is available. Lots of open source software is available, but you may need to negotiate with a technician for them to install it! You also need to use software with which you feel reasonably competent and confident. If you are not already experienced with certain software, how much time can you devote to learning to use it in the timescale available? The first choice is between customising a generic application program (with recorded macros or written program code) and writing your own bespoke program in a programming language. With generic software, the next choice may be between applications such as a spreadsheet program (such as OpenOffice Calc), or a database management program (such as OpenOffice Base) for managing a database. As you may be aware, a spreadsheet program is not designed to manage a relational database, although one of its lookup functions can be used to retrieve data from a table. While a relational database management program is specifically designed to handle relationships between data tables, you may have found it more complex to learn. Opportunities for creating macros in commonly used generic application programs vary, but the following table gives you a guide: Application

Recording

Writing

Microsoft Office Word

In VBA

In VBA

Microsoft Office Excel

In VBA

In VBA

Microsoft Office Access

In Access action language or VBA

OpenOffice Writer

In Dispatch API language

In OpenOffice Basic, Python, BeanShell or JavaScript

OpenOffice Calc

In Dispatch API language

In OpenOffice Basic, Python, BeanShell or JavaScript

OpenOffice Base Adobe Dreamweaver

In OpenOffice Basic, Python, BeanShell or JavaScript As a command

In JavaScript

With programming, you may be able to create your own user interface (or ‘front end’) for a database and choose between manipulating it with a database engine and handling your own files. You may even be able to choose between different programming languages that you have learned. If in doubt, ask your teacher for advice. Not all of your system has to be completely computerised and there is no reason why you cannot use one program for database management and a second program for a mail merge that imports data created by the first.




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System life cycle

You have previously studied the theory of the system life cycle. It is now necessary to use that theory and put it into practice. The essential stages in the system life cycle are represented in the following diagram. analysis

design building and testing changeover evaluation and maintenance

Solving the problem that you choose for your project will involve working through similar stages, like a systems analyst. However, you need to be aware that in this coursework, ‘Implementation’ is used to mean the building stage, not the changeover stage. In your Analysis stage, you will use fact-finding techniques to collect information from your client. This will be used to describe the problem, the current solution, the objectives of a new solution and one or more possible new solutions. In your Design stage, you will write a project plan, ideally with a Gantt or similar chart. You will write detailed descriptions of your proposed solution, including a system flowchart. You will also justify your choices of hardware and software. In your Building stage, you will build your solution from your Design and write Technical Documentation for it. You will write a detailed description of the solution, including input requirements, processing, storage, data structures, hardware and software requirements, together with any backup, security and data recovery procedures. This should be a sufficiently clear and complete set of documentation of what you build that it would enable future maintenance or modification. In your Testing stage, you will write a test strategy. This will include a test plan containing test data and expected results of tests of validation checks, and processing and printing. This section should correspond with all the objectives you set out in the Analysis stage. You will also show evidence of test results, ideally including those for all three types of test data for validation checks. You will produce a clear and complete user guide in less technical language than your Technical Documentation. In the Evaluation and Development stage, you will write an evaluation of how effectively your solution achieves all the objectives in your Analysis and some suggestions for possible future development.




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The write-up

You have seen that your project will involve working through certain stages of the system life cycle, like a systems analyst. You should write up your project as if you were a systems analyst documenting the job for your client. The material needs to be clear and presented in a logical order. When you write up your project report (or ‘write-up’), a good way to organise your work and reduce the risk of leaving something out is to use the following suggested minimum set of headings and subheadings. You might need to add many more levels of subheading: Contents

Analysis Description of the problem Objectives Description of existing solution Evaluation of existing solution Description of possible solutions Design Action plan System flowchart Method of solution (designed) Hardware requirements Software requirements Technical documentation Testing Test strategy Test results User guide Evaluation and development Evaluation Future development If you are word processing your project report, which is strongly recommended, you should consider the following advice: • Create a folder for your coursework • Create a single, suitably named, word-processed document in your folder with: – a footer containing: – your name, centre number and candidate number – automatic page number – force sufficient ‘page breaks’ (usually Ctrl+Enter) to create enough numbered blank pages for substituting hand-drawn design pages later, but original documents should go in an appendix – a title – a title and your name as a cover sheet, followed by a page break – all the headings and subheadings suggested above – doing this at the outset is a minor chore, but helps to establish an ordered structure into which you can write and is likely to stop you getting ‘lost’ in the report and save you time in the long run. Ideally, you should apply suitably modified styles, Heading 1, Heading 2, Heading 3, etc., to all your headings and any subheadings you add (except the Contents heading) to ensure uniformity of formatting for each level of heading and subheading.




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•

• •

Create backup copies of your coursework every day. Not only does this help you to develop good habits but, in view of your great investment of time and energy, it may also preserve your sanity in case of data loss. There often is no ‘Recycle Bin’ (or ‘Trash’) for your user area on a network and the school’s file servers and backup system could malfunction! If you rely entirely on a USB flash drive, what would you do if it were to become damaged or lost? Ideally, to remain ‘fire-proof ’, you should maintain up to three up-to-date backup copies, one at school, one in transit and one on any computer you use at home. For the transit medium, you have three alternatives: – USB flash drive – email – you may need to convert your folder of work to ZIP format to keep within the maximum attachment size – SkyDrive (http://skydrive.live.com) or similar free online storage. Glue together the components of drawings and screenshots with any annotation callouts, so that they each behave as a block of text, rather than as ‘floating’ graphics, using a blank drawing object (OpenOffice Writer) or a ‘drawing canvas’ (Microsoft Word). Make sure that you know how to insert pairs of ‘section breaks to the next page’ within your document, between which you can change the orientation from portrait to landscape for wide commented code, tables or diagrams.

General things to note

You won’t be awarded marks for fancy formatting but using different styles for different levels of heading, using bulleted lists and other formatting can help to harmonise the appearance of the document, and make it easier to navigate. One mark is available for creating a table of contents for your project report. Provided that you have applied the styles Heading 1, Heading 2, Heading 3, etc., it is simple to create the table of contents automatically under the Contents heading and to update it if headings or pagination change. You should include at least two levels of headings in the table of contents. A table of contents helps the reader navigate and understand the report. If you leave creating the table of contents until just before you print your report, there is no risk that you will fail to update it. However, if you use Microsoft Word, create your table of contents early on and update it frequently. You can also use the hyperlinks in its page numbers to navigate electronically round your report while you are still writing it! Unlike Papers 1 and 3, the number of marks awarded for each section does not indicate the number of points you need to make. As you have an extended period of time to complete this assessment, you are expected to put in a lot more detail for your marks. In the rest of this guidance document, we will work through each of the main sections of the coursework project, offering advice on how to approach them. As this is coursework, it is not possible to present you with ‘exemplar answers’ because everyone’s writing style and approach is different. Instead we offer you some guidance and some example material to demonstrate some of the points being made. Please note that the following material is original and is not advice provided by University of Cambridge Local Examinations Syndicate.




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Coursework guidance Analysis

This division of the assessment criteria has five sections in which you can earn up to a total of 11 marks: 1

Description of the problem

[2]

2

Objectives

[3]

3

Description of the existing solution

[2]

4

Evaluation of existing solution

[2]

5

Description of possible solutions

[2]

The section numbers correspond to those of the similarly named sections in the assessment criteria. The maximum number of marks that it is possible to score for each section is indicated in brackets [ ]. 1 Description of the problem

The heading ‘Description of the problem’ can be somewhat misleading because in order to get full marks (2 marks) you have to describe the background of the business or organisation, as well as a description of the problem. It is a common error to forget to describe both. You need to describe the nature of the business/organisation in order to put the problem into context. The reader needs to understand the problem fully before they can assess if you have provided the correct solution. As each candidate chooses the particular problem they wish to solve, it is essential that you explain the problem as clearly as possible because the reader will not be familiar with it already. Set out all the details as thoroughly as you can. Do not rely on the reader making the same assumptions that you have. Write the material so that it can be understood by a third party and not just by your teacher or client. Here are a list of the key points you should include in this section: Description of the business/organisation: • the name of the business/organisation • the purpose/type of business/organisation, e.g. a shop, a library, a school, a charity • what the business/organisation does, e.g. sells clothes, loans out books, fund raising • where it is based, e.g. name of a large city, small village, tourist town • the number of employees, e.g. 2 full-time shop assistants, 3 full-time librarians and 1 parttime bookcase sorter, 30 volunteers with money buckets • the set up of the business/organisation, e.g. the clothes stop has 10 copies of each clothing item on the shop floor and up to 20 more in the stock room with anything else available from the catalogue in 5 days • the number of customers/users there are each day/week/month/year (as appropriate). Description of the information processing problem to be solved: • the kind of information processing system they currently use, which may be manual, or even rather disorganised • in general terms, the things that need to be improved.




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You can clearly see that the 2 marks awarded for this section are not for 2 specific points. You need to include all the bullet points listed above to have covered the ‘Description of the problem’ section satisfactorily enough to score the 2 marks. Example material for ‘Description of the problem’ Description of the problem

‘Tuddenham Village Library is a small public library based in a rural town in France. The library lends books to members within a 10 mile radius of the town. It stocks about 10, 000 books that range from very popular titles to more specialised titles. The library is situated on two floors, each containing rows of shelves with books sorted by subject area. There are also a few areas with seats and tables called ‘reading areas’ where people can read books without having to borrow them. There is no separate stock room for the library; all the books are stored on the shelves. There are about 6000 members of the library. The average number of members that visit the library in a six-day week is about 500. Saturday is the busiest day; sometimes there can be up to 300 just in one day. There are three full-time library workers (librarians). Description of the problem to be solved

The library uses a completely paper-based system to keep records of members; what books they have out on loan; when they are due back and if there are any outstanding fines for overdue books. All of the input, processing, storage and output of the paper-based system takes place at the front desk. A filing system is used to store the members’ names and contact details on cards in alphabetical order. Another card-based filing system, known as the ‘book’ catalogue, stores bibliographic information (title, author, publisher) about each book in the library. These cards are filed in alphabetical order by book title. Each book has a unique code given to it by the library that is based on the subject area and book title. This is stamped onto the spine and inside cover of the book. The code is also recorded in the book catalogue, along with the number of copies the library has of the book. The number of copies of a specific book the library chooses to stock will depend on the popularity of a book. There are multiple copies of some books, but single copies of others. The number of copies is recorded in the library’s book catalogue. If the library receives more than 20 complaints in a one month period about the poor availability of a specific book, they will order more copies of that book. Each library member has a membership card and 10 paper tickets that are needed to borrow books from the library. The members are only allowed to borrow a maximum of 10 books at any one time and each one must be returned within 21 days of taking it out. Each book in the library contains a ticket on the inside cover that contains the book’s title, the author name, the book’s unique code and a space to stamp the return date. The librarians rotate their duties so that at any time during the day, there is one worker at the ‘front desk’, one worker re-stocking the shelves with returned books, and one who walks around doing general neatening up of the shelves, and putting books away that have been left in reading areas. All the workers are expected to answer queries from the members. Members select books from the shelves. When a member wants to borrow a book they have to present a membership ticket at the front desk. The library worker has to make sure that no one takes out a book without exchanging it for one of their tickets.




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The lending process requires the librarian to remove the book’s ticket from inside the cover, then stamp the ticket with the return date. The stamp is a manual wind-up stamp with an ink pad. Each morning, a librarian has to make sure that the date on the stamp is set to 21 days from the current day’s date. The stamped book ticket is then attached to one of the member’s 10 tickets and stored in a system of filing cabinets that the workers refer to as the ‘loan records’. Within the cabinet there are folders to hold the tickets, which are sorted alphabetically by book title. The inside cover of the book is also stamped with the return date for the member’s reference. When a member returns the book, the librarian locates the relevant book ticket from the filing cabinet, removes the member’s ticket and returns this to the member. They then replace the book ticket back inside the book. The librarian checks the return date stamp; if the book is overdue, the library member gets charged a small fine depending on how many days it is overdue. The book gets put into a return-toshelf trolley, known as the ‘returns trolley’. A library worker re-stocks the book shelves three times a day using the returns trolley. If a book is overdue, the librarian works out the fine using a calculator. If the member is not able to pay the fee at that moment, then an invoice is written out. A top copy of the invoice is given to the member, and another copy is filed in a separate filing tray. This tray is checked at the end of each week and reminder letters are written. Once an invoice has been paid, it is thrown away. When a member wants to know if a certain book is available, the librarian has to first look up the title in the book catalogue to see if the library stocks it. The librarian can then tell the member the part of the library where the book should be found. If the customer returns from the shelf to inform the librarian that book is not there, the librarian will check the loans file to see if another member has taken it out on loan. The librarian will search the filing cabinet by book title, to see if the book’s ticket is in the file attached to another member’s ticket. If it is there, the librarian can inform the first member when the book is due back. If the book’s ticket is not in the file, then the librarian will check to see if it is in the ‘returns trolley’. This is only possible when the returns trolley has not been taken to re-stock the shelves. The members can only reserve books that are already out on loan. They cannot call the library and ask them to reserve a book off the shelf for them. If the member wants to reserve the title after discovering it is out on loan, the librarian has to find the book ticket in the loans filing system and attach a note to it. The note informs the librarian of the member who wants to borrow it next. This means the librarian can notify this member when the book is returned. A note is also made in a ‘Reservation’ notebook, of the date the book is due back and what member has reserved it, along with a number to call once the book has been returned. The library’s manager is under pressure to reduce the cost of running the library and needs to be able to run the library with a reduced number of staff. A lot of space is occupied by filing cabinets and members sometimes have to wait a relatively long time to be served at busy times. The manager has asked whether a computerised information system to replace the existing paper-based system would help to run the library more efficiently. The new system would need to: • Create and store records of books, members and loans. • Record the return of a book and calculate the fine for an overdue book. • Create an invoice and possibly a reminder letter for each outstanding fine. • Produce reports of overdue books. • Handle members’ enquiries about books stocked and the dates that they are due back from loan. • Handle reservations for books already out on loan.




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Comment You can see the level of detail that has been supplied. Every possible piece of information that is important to how the business works has been included and every type of situation covered. All these details are required in order for you, and anyone reading your report, to be able to understand the problems with the current system. Remember, you must describe both the context of the problem (i.e. a description of the organisation or business) and the nature of the problem (i.e. a description of the problem to be solved).

2 Objectives

It is common to confuse aims and objectives. You can think of them like this: Aim – the overall aim is a single sentence describing what you are trying to achieve Objectives – are the details of how this general aim will be achieved For example, a systems analyst working for a charity organisation might state the following aim: Aim of solution – To create a computerised membership system to improve administration and sending letters and emails to members There are many ways that this could be achieved, so you need to use the objectives to explain how you plan to achieve the aim. The following are examples: Objectives: 1. To save paper and storage space by using a computerised database to store member, book and loan records. 2. To save time when creating well-presented letters and emails by using a database query as a data source for some form of automated mail merge. The objectives are very important because the planning, testing and evaluation parts of the coursework will refer back to them. So, if you do not specify the objectives clearly at this stage, you will lose marks here but you will also tend to lose focus in your design and lose marks in the building, testing and evaluation sections as well. For example, without knowing the nature of the problem to be solved and the detailed objectives to be achieved it will be very difficult for you later to evaluate the success or failure of the solution. Therefore, getting this section correct is vital. You should make a numbered list of testable objectives for your proposed solution. This is easy to automate if you are word processing your report and makes it easier to refer back to them later. You should: • in each case use: – general business terms to state what benefit you aim to achieve in what situation and – computer-related terms to state what you will provide




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•

make sure that you include all the areas you will test later, such as: navigation menus and command buttons input and associated validation and verification storage processing and output.

– – – – – –

Further examples: 1. Save ____ for a worker moving between ____ in the database by providing navigation buttons to return to the ____ or open frequently used ____. 2. Save ____ for a worker searching for a member’s ____ when answering a ____ enquiry by providing a form based on a ____ to search the customer ____. 3. Save ____ and make the calculation of a member’s ____ from their ____ more ____ by providing a ____. 4. Save ____ when printing a ____ list, by providing a ____ button on the ____ menu. The 3 marks awarded for this section do not indicate that there are only 3 points to make. To get full marks, you need to write a comprehensive, numbered list of testable objectives for your proposed solution (with at least ten objectives), with each objective phrased in terms of both general business terms, for example: • to save resources • to save time • to make a named process faster and computer-related terms, for example: • using a form to create a record • using a form to edit a record • sorting or searching database records. Often candidates specify an objective as being ‘to make a particular process faster’, ‘to save time’ or ‘to save resources’, but they fail to mention how this will be achieved and so score badly. To score higher marks, you need to make sure that your objectives are also phrased in computer-related terms. Each objective needs to be something that can easily be tested by producing some screen or printed output. Testing your objectives later allows you to evaluate the extent to which you have solved the problem. Try to avoid general objectives such as ‘create a database’ as, although you would be able to provide plenty of evidence, a complete set of evidence would be very long! 3 Description of the existing solution

If there is a current solution (even if it is manual or very disorganised) for the problem, then you should describe the flow of data within that solution. You can use words or diagrams, but they should reflect the input-storage-processing-output model of a computer system. For a full description of the current solution, make sure you include: • data input requirements such as: – data capture methods including: – input devices – examples of data collection or capture forms – data dictionary (see example below) – detailed specifications (where applicable) for the accuracy, quality, file format and other technical features of input data Cambridge IGCSE Computer Studies



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• • •

data storage requirements data processing techniques data output requirements such as: – data output methods including: – output devices – examples of hard copy output – detailed specifications (where applicable) for output data.

Example of an analysis data dictionary for two specimen data items in one specimen table tblMember Field Name

Description

Example

Data Type

Range

Format (for display)

MemberNo

A unique identifier used to identify each member.

Uri Cooper’s member number is 103426.

Integer

100001 to 999999

No comma to separate last three digits.

MemberFirstName The first name of the member.

Member Text/String number 103426’s first name is Uri.

1 to 25 characters

Capitalise each word.

…

…

…

…

…

…

If the existing system is a manual, paper-based system, then it might involve handwritten notes on pieces of paper. You can apply the list above to consider all the processes the paper-based system might have an equivalent for. For example: • data capture: – librarian takes a paper ticket from inside the book and a member’s ticket from the borrower – the book’s ticket is stamped with the return date. • data processing techniques: – librarian attaches member’s ticket to date-stamped book ticket and files them – when a book is returned, a librarian finds the book’s ticket, gives the member’s ticket back to the borrower, calculates any fine due, places the book on the returns trolley and creates an invoice for an unpaid fine – when a member asks for a book a librarian looks for its record in the catalogue – if a book in the catalogue is not found by the member, then the librarian looks for its record in the loans files – if the requested book is not out on loan, the book is looked for on the returns trolley – copies of invoices for outstanding fines are checked weekly to decide who needs a reminder letter – to reserve a book on loan, a librarian finds the book’s ticket in the loans files, attaches a note to it and records the requesting member’s contact details in the reservation notebook. • data storage requirements: – card catalogue stores details of books stocked by the library – card filing system stores the members’ names and contact details – book tickets are stored in books in the library – filing cabinet store tickets of books on loan




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– – – •

returned books on returns trolley filing tray stores copies of invoices for overdue fines reservation notebook stores the date a book is due back and the name and phone number of the member reserving it. output requirements: – an invoice for each unpaid fine – a reminder letter to a member who has not paid an invoiced fine.

To get full marks, you must include as many as possible of the bulleted points, not just 2 of them. Remember that, for some problems, there may not be an existing solution and so it will not be possible to score marks in this section or for evaluating the current solution. 4 Evaluation of existing solution

You should discuss the advantages, disadvantages, strengths and weaknesses of the existing solution to the information processing problem. To get full marks you must also include any suggested improvements. When considering disadvantages, think of answers to the following questions: • What goes wrong? • When does it go wrong? • What issues does this create? Example material for the library described above

Advantages: • Storing the tickets of books on loan in alphabetical order of title makes it relatively easy to determine the number of copies of any book that are currently out on loan and so determine if there should be any remaining copies in the library. Disadvantages: • If a member loses one of their 10 tickets then they are unable to borrow up to 10 books and it is possible for somebody else to borrow books on their ticket. The library’s records would not be accurate and a member could be charged fines or even charged for a lost book that they had not even borrowed. • A librarian only discovers a book is overdue when the member returns it, so that the book remains unavailable to members browsing the shelves and the member who borrowed may build up a large fine without receiving a reminder. • To get a list of overdue books would require examining the return dates on all the tickets of books on loan because they are not stored in date order. • It is not possible to produce any monthly usage statistics because it would be too time-consuming. • Fines are not automatically calculated. The library staff have to notice from the ticket that the book is overdue and manually calculate the fine. • There is no permanent record of paid invoices for fines, so that the library’s manager cannot refer to such a record if a member later disputes the fine. • The system would only work correctly if each book had the correct ticket inside the cover. If for any reason a ticket inside a book were wrong, when the book was returned the library staff would be unable to return the member’s ticket. Improvements: • Computerised records of loans would make it easy to keep permanent records of loans and fine payments and to produce a wide variety of usage statistics.




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5 Description of possible solutions

There will usually be more than one way to solve your chosen problem. To score full marks in this section, you need to clearly describe your proposed solution as well as at least one other solution. An example approach is to include three possible solutions: • extending the current system (paper-based or computer-based) • using a generic software application package to create a new computer-based system • using a programming language to write a custom computer-based solution, or using a different generic software application package, or using two generic application packages. Example material

Possible solution 1: Changes to the present paper-based ticket system Amendments could be made to the current manual system that would improve the operation of the system. Each book could have 2 tickets and each member could have 20 tickets and 2 would be needed for each book taken out on loan. One set could be stored in the filing tray, sorted in alphabetical order of the title, and the other set could be filed in a different tray, sorted in date order. A record sheet could be kept listing the book title and author. At the end of the month this list could be used to calculate the usage statistics. Also, the librarians could create a list of overdue titles by looking at the tickets stored in date order. Possible solution 2: Generic software package A solution could be written using the database part of a generic software package, such as Microsoft Access, to provide a computerised information system to replace the existing paper-based system for: • Creating and storing records of books, members and loans. • Recording the return of a book and calculating the fine for an overdue book. • Creating an invoice and possibly a reminder letter for each outstanding fine. • Producing reports of overdue books. • Handling members’ enquiries about books stocked and the dates that they are due back from loan. • Handling reservations for books already out on loan. This would have the advantage that staff may be familiar with the other parts of the Office suite and make it easier to introduce the new system. Any staff familiar with Access would also be able to write customised queries, design forms or reports. Support would also be available via online communities. Possible solution 3: Bespoke computer-based solution A systems analysis could be used to investigate the current system and then a specific application could be written in a programming language which would be specific to the library’s needs. As with the other sections, you will not get the full 2 marks simply by listing 2 points, you need to cover this section in detail. Finish the analysis section off by stating which of the possible solutions you are choosing as your proposed solution. Design

If you have not already done so, you should write an action plan showing how you intend to complete the stages of the system life cycle for your project by the intermediate and final deadlines set by your teacher. Cambridge IGCSE Computer Studies



15

It may help to make your design well-structured and easier to understand, modify and debug, if you start by drawing a structure diagram to represent a top-down design. Use stepwise refinement to split your solution into successively smaller sub-solutions. It should be possible to read the sequence of steps at any level from left to right. You will need to show the overall design in the form of a system flowchart. You will need to specify the input and output requirements and specifications, as well as requirements for data structures, processing, storage and navigation. This division of the assessment criteria has five sections in which you can earn up to a total of 14 marks: 6

Action plan

[3]

7

System Flowchart

[2]

8

Description of method of solution (designed)

[3]

9

Hardware

[3]

10

Software

[3]

6 Action plan

By this stage, you should have decided what problem you are going to solve, listed the objectives of the new solution and chosen an overall method of solution. If you have not already done so, you now need to plan the order in which the tasks will be carried out, and to assess how long it will take. This requires a formal action plan. Your action plan must relate back to the list of objectives you set out in the analysis section as well as the system life cycle. Include all the major stages of the system life cycle as headings, and then add appropriate subheadings to break the stages down into smaller tasks related to the objectives of your chosen solution for the problem. The plan should include sufficiently detailed descriptions of activities, with dates shown. The plan is more useful if it shows the availability of scarce human resources such as your client and of scarce physical resources such as a barcode scanner that you may only be able to borrow for a period of three days in February. To score full marks for this section (3 marks) you must display your plan as one of the following charts: • Gantt chart • Project Evaluation and Review Technique (PERT) chart • Critical Path analysis (which can also be done using a Gantt chart). A list of things you might want your action plan to include, is as follows: • phases – e.g. analysis, design, implementation etc. • tasks – a basic unit of work • activity – an optional group of tasks that form a sub-phase • time allocation – shown in days • milestones – significant events/dates against which progress can be measured, such as intermediate and final deadlines set by your teacher Cambridge IGCSE Computer Studies



16

• • •

dependencies – where the start of one or more tasks is dependent on the finish of another the critical path – the sequence of dependent tasks that determines the overall duration of the project progress of tasks – the amount of a task completed relative to the planned time or ‘baseline’.

Project management software such as Open Workbench or Microsoft Project allows you to create a project plan and display it in the form of a chart. Open Workbench is open source project management software that is freely available from www.openworkbench.org. If you do not have access to project management software, then you can create your own chart using a spreadsheet or word-processed table with shaded cells . All you need to do is write your list of tasks and then include a series of dates as column headings and shaded cells, like the image below. Make sure you provide a key or legend so that the reader knows how to read the chart. Example of a spreadsheet Gantt chart showing the early stages of a coursework project

Name

Start

Finish

Analysis

09/01/2012

11/01/2012

09/01/2012

09/01/2012

10/01/2012

10/01/2012

11/01/2012

11/01/2012

Monday

Tuesday

Wednesday

Thursday

Friday

Monday

Tuesday

09/01/2012

10/01/2012

11/01/2012

12/01/2012

13/01/2012

16/01/2012

17/01/2012

Description of problem & Objectives Description & evaluation of existing system Description of possible solutions Design

12/01/2012

17/01/2012

Action plan

12/01/2012

13/01/2012

16/01/2012

16/01/2012

17/01/2012

17/01/2012

Hardware

17/01/2012

17/01/2012

Software

17/01/2012

17/01/2012

System flowchart

Saturday

Sunday

14/01/2012

15/01/2012

Description of method of solution

As with the other sections, the 3 marks are not awarded for 3 specific points that you make. They are awarded for a complete, detailed plan that includes a Gantt or PERT chart. 7 System ﬂowchart

You can use a system flowchart to demonstrate how the new computer-based system will work. This should include all of the stages that would be in the final solution. To get full marks, you need to make sure that you have used the symbols correctly. Refer to Table 6.2 in the coursebook for a complete list of the flowchart symbols.




17

Although the specific content of a system flowchart will vary from project to project depending on the problem, there are some key things to remember for all system flowcharts: • emphasis is on input, processing, storage and output • more emphasis on the different sorts of hardware than other sorts of flowchart as there are special symbols for manual (keyboard) input, three symbols for different storage hardware and two symbols for screen and printer output • easier to read if the data entry operations are situated at the left or top; data processing operations are in the middle and storage and output operations on the right or bottom • use separate symbols for each sort of processing used by the user/processor • only describe processing in a general way, so only limited detail of processing required • include START and STOP terminator symbols • the words used in the flowchart must relate to your solution to your problem • make sure that both the shape of the symbols used and the text/instruction within a given symbol are both correct. When drawing your system flowchart, you need to depict all the steps of input, processing, storage and output that the system will need for the proposed new solution. Points to note are: • It might help to think of the system flowchart as a series of stages that make up the system. • Whenever appropriate, work through the stages chronologically (in order of how they would happen) to help you be systematic, drawing it from left-to-right and top-to-bottom, as in the example answer and those in the coursebook. • Think of one stage at a time: what input, process, storage or output symbol does the stage need? Label each symbol. • Join together pairs of symbols with flow arrows. The arrows represent the flow of data between symbols and the flow of control to and from terminator symbols, so make sure they point in the correct direction. (You do not have to label the arrows with a list of the data items being transferred, but you might find this helps.) • Use the full range of symbols shown in the coursebook to give as much information as possible about types of processing and hardware used for storage and output. To decide what stages should be shown in your system flowchart, think about the following: • Data entry: how is data entered into the system when a client deals with the organisation, or a user queries the system? Draw the appropriate manual or general input (parallelogram) symbol (appropriately labelled) with a flow arrow to the next step. • Data processing: what sort of processing is performed by the system? Draw the appropriate manual collection, sorting, merging, collating or general process symbol, and label it appropriately. • Data storage: what sort of storage is the data sent to and retrieved from? Draw the appropriate online, hard disk or tape storage symbol, and label it appropriately. • Output of data: how is data output to the client or user? Draw the appropriate VDU or document output symbol, and label appropriately. • Other: further steps of input, processing, storage or output, until complete.




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Example of a system ﬂowchart for part of the library problem START

Generate menu and process option selected: Enquiry, Loan or Report Enquiry

Enter author or title requested

Search book records for author or title

Details of book(s) or message that none is stocked

Scan membership card’s ID barcode

Library database

Note: Two aliases of the same library database are shown.

Scan book’s ID barcode

Menu: Enquiry, Loan or Report

Loan Report

Search for member details, loans and fines

Member details, loans and fines

Search for last month’s loans and count books lent and members who borrowed

Report of no. of books lent and no. of borrowers

Library database

Use member and book IDs to create new loan

Member details and fines and updated loans

For each stage of the flowchart, make sure you consider what type of symbol is appropriate. And above all, remember to make it relevant to the problem! Remember that the 2 marks awarded for this section do not mean you only have to include 2 processes in your flowchart. You have to make sure your system flowchart shows the complete system and uses all the correct symbols. 8 Description of method of solution (designed)

The description of your proposed method of solution involves the following: • output designs (drawings of plans, not screenshots of prototypes) • input designs (drawings of plans, not screenshots of prototypes) • data storage designs • processing designs • command button and menu designs. To get full marks you must remember the following: • do not include screenshots of prototypes in this section because it is meant to be completed before you start making the prototype (even if that doesn’t happen in reality) • make sure that all of your drawings are clearly annotated using keys, footnotes and callouts (these are text boxes with arrows that automatically adjust themselves when you move the text box, sometimes with a coloured handle) • you can either draw free-hand using pencil, or draw on-screen using a computer. All computer systems involve input, processing, storage and output. The systems analyst’s overall aim is to produce a system that produces the specified outcomes. Therefore, the designer typically starts by designing the output, then the input required to produce the output and so on, in the order listed above. You may find it helpful to follow this same order yourself.




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Output designs

To gain full marks, you need to describe your output designs clearly and in detail. You should use a pencil or computer to draw your designs for: • output spreadsheets, charts or screen forms/displays • any printed reports • any other form of output. You should also include data output requirements and specifications, which may be similar to the ones for the existing solution. Your drawings should be clearly annotated using keys, footnotes and callouts (text boxes with arrows). Remember to refer back to the common issues when designing on-screen forms/pages. Return to your objectives and chosen solution to help you consider what output designs you will need. Example of a spreadsheet screen output design, hand-drawn on a printed layout grid

Screen output design for ‘Search Results Sorted by Title’ sheet A 1 2 3 4 5 6 7 8 9 10 11 12 13

B

C

D

E

DJTrax Search Results Sorted by Title Track Title No 563 Atom Bomb

……. ……. ……. ……. ……. ……. ……. ……. …….

……………………….. ……………………….. ……………………….. ……………………….. ……………………….. ……………………….. ……………………….. ……………………….. ……………………….. You Want It Back

Propellerheads

11

Artist

F

G

H

Return to main menu

Fluke

Duration Medium Rating (mm:ss) 5:02 DVD 2

Backed up? TRUE

Date added 07/02

………………….. ………………….. ………………….. ………………….. ………………….. ………………….. ………………….. ………………….. …………………..

………… ………… ………… ………… ………… ………… ………… ………… ………… 6:00

………… ………… ………… ………… ………… ………… ………… ………… …………

……… ……… ……… ……… ……… ……… ……… ……… ………

………… ………… ………… ………… ………… ………… ………… ………… …………

………… ………… ………… ………… ………… ………… ………… ………… …………

MP3

3

FALSE

28/8

14

Row 2: Labels. Rows 3 to 13: Results of searching for tracks lasting between 5 and 6 minutes, sorted by title. ‘Return to main menu’ button triggers ViewMain macro, which navigates to Menu sheet. Input designs

To gain full marks, you need to describe your input designs clearly and in detail. You should use a pencil or computer to draw your designs for: • input spreadsheets or screen forms • any other form of input. You should also include: • data input requirements and specifications, which may be similar to the ones for the existing solution, a list of validation rules and informative error messages • a list of verification methods and informative error messages. Your drawings should be clearly annotated using keys, footnotes and callouts (text boxes with arrows). Spreadsheet designs should include row and column numbers and letters, since formulae you design later will refer to cells shown here.




20

Before you can draw your input designs you need to decide how the required data will be collected. Will it be automatic (e.g. sensor, barcode scanner) or manual (e.g. keyboard) entry? Return to your problem and chosen solution to decide on the best methods for data input. Example of a drawn input design

Input design for ‘Invoice’ sheet A

B

C

D

E

1

Central Jakarta Tel: 62 21 1234

3

www.a2z.co.id

4

Cash Sale

G

Main menu

A - Z Supplies LLC 2

F

Print invoice

02-Feb

5 6

Quantity

Code

Description

Item Price

Extended Price

7

3

6

Grommet

$0.50

$1.50

8

1

2

Nibbler

$2.00

$2.00

9

6

1

Widget

$3.50

$21.00

10

2

3

Dibber

$1.50

$3.00

11

5

5

Dobbler

$5.00

$25.00

Subtotal

$52.50

Sales Tax

$10.50

Total

$63.00

12 13 14 Sales Tax Payable

15 16

Spinners to speed up adjustments to Quantity. Represents input cells

TRUE

Check box linked to cell G15.

Cells A7:A13 have Validation rule of whole number between 0 and 500 and error message “Please enter a value between 0 and 500”. Cells C7:C13 have Validation rule of limited to list in Stock Database and error message “Please select a code from the Stock Database”.

Data storage designs

To gain full marks, you need to describe your data storage designs clearly and in detail. You should include: • the file types to be used by generic application software • the structures for any files that program code will manipulate • the structure of any database tables and their relationships • methods of controlling access to the data • the hardware needed for the data storage and backup. You should use a pencil or computer to draw your design for any relationships between database tables. Your drawings should be clearly annotated using keys, footnotes and callouts (text boxes with arrows).




21

Example material for data storage design

•

•

The database will use Microsoft Access’ ACCDB file format for storage. Or, the bespoke program code will manipulate text files structured as follows: – StudentSubject file contains fixed length records consisting of the following fields: StudentName (Text/String, 50 characters), Class (Text/String, 5 characters), SubjectCode (Text/String, 10 characters). –… The design data dictionary (showing the structure of just three specimen fields in one specimen database table): tblMember

Field Name

Key Data (P/F) Type

MemberNo

P

MemberFirstName …

…

NoOfTickets

•

• • • •

Field Size

Number Long Integer

Validation Check(s)

Range check Between 100001 And 999999

Text/ String

50 Presence characters check

…

…

Number Byte

Validation Rule

…

…

Range check Between 0 and 10

Default Value

Format (for display)

-

No comma to separate last three digits.

-

Capitalise each word.

…

…

10

The relationships of the database tables:

tblMember

tblLoan

MemberNo MemberFirstName MemberLastName …

MemberNo BookNo DateLent DateDueBack

(to other tables)

The method of controlling access to the data will be to set a database password of ‘GuEsS9#9mE’. The hardware needed for data storage is the computer’s HDD and a USB flash drive (minimum 1GiB) for backup. Backup will be performed manually at the close of business each day by copying ____ from ____ to ____. Data recovery will be performed by copying ____ from ____ to ____.

Processing designs

The processing designs must include all of the following: • structure diagram for top-down approach • spreadsheet formulae or database queries drawn on grids • flowcharts or pseudocode for algorithms for any program code you will write • list the steps for macros that you will record • you must annotate at least one module of pseudocode, program or query code to explain it, preferably using comments within the code. Your drawings should be clearly annotated using keys, footnotes and callouts (text boxes with arrows).




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Structure diagram

The processing design determines how the system will work; how input data become output information. You should start by drawing a structure diagram for a top-down approach to your solution. The advantage of this diagram is that it will create a set of smaller, simpler solutions for you to tackle. You might find it helpful to break down the solution according to the input-storage-processingoutput model of computer systems. Write out all the steps your system would need, then decide if these are input, processing, storage or output steps. Then decide if these can be broken down to even smaller steps. Example structure diagram for solving part of the library problem

Example structure diagram for ‘Create loan records for a member’ Create loan records for a member

Create new loan records * for member while NoOfCurrentLoans