1. Topic 2 – Techniques involved in Systems Analysis Unit 1 – Database Analysis and Design Advanced Higher Information Systems St Kentigern’s Academy

2. What I need to know The techniques involved in systems analysisThe techniques involved in systems analysis –Explanation of a feasibility study: economic,economic, legal,legal, technical,technical, time.time. –Description and exemplification of project planning: importance of plan, elements in plan (including time, resources, and costs), application and monitoring of plan.

3. What I need to know The techniques involved in systems analysis cont’dThe techniques involved in systems analysis cont’d –Identification and explanation of investigative techniques: observation,observation, document sampling,document sampling, questionnaires,questionnaires, interviewing.interviewing. –Description of results from investigation, including: background information,background information, departmental objectives,departmental objectives, description of components in existing system,description of components in existing system, organisation procedures.organisation procedures. –Description and exemplification of systems specification based on results of investigation and modelling: functional requirements,functional requirements, restrictions on development.restrictions on development.

4. Explanation of a feasibility study Once presented with a project proposal, the project leader will carry out a feasibility study. The feasibility study must look at the project in sufficient depth to be able to provide information that: – –either shows that the development of the new system is cost-effective, – –or shows why the project should not continue.

5. Explanation of a feasibility study The feasibility study should be conducted relatively cheaply and within a fairly short time frame. There are no legal or contractual requirements at this stage. The findings of the feasibility study are presented to the client in the form of a report. This report indicates costs, benefits, alternatives and appropriate recommendations.

6. Explanation of a feasibility study There are four aspects of feasibility that must be considered in any feasibility study: – – economic feasibility; – – legal feasibility; – – technical feasibility; & – – time feasibility.

7. Economic Feasibility This deals with the costs involved in the development of the project. The client will want to know the cost of each option and what they get for their money. A system is only economically feasible if the benefits of the development outweigh the costs. For this reason a cost benefit analysis is carried out. The cost-benefit analysis will identify: – –the costs involved in the development; – –the benefits that will result from the development; & – –the break-even point when the new system stops costing money and starts making profit.

8. Legal Feasibility This considers the legal issues associated with the development of a new information system. Particular notice must be given to the legislation outlined in: – –Data Protection Act (1998) Will the new system contain details of living persons? – –Computer Misuse Act (1990) The potential for hacking and plating viruses must be considered. – –Copyright, Design and Patents Act (1988) The issue of software licensing is important.

9. Technical Feasibility The technical feasibility study must identify the technologies that will be necessary for the proposed system to function correctly. Once identified, the technical feasibility then considers whether or not the technologies necessary are currently available. – –If the required technologies are available, the technical feasibility must determine whether or not the client already has the necessary resources. If not, the resources that must be acquired are identified and suitable hardware and software recommended.

10. Schedule/Time Feasibility The time necessary to develop a new information system is considerable. For this reason, the time feasibility must consider not only the time needed to carry out the development but how this will affect the client. Time feasibility must take account of: – –overall development time for the project; – –events during the year that the business is already committed to; – –when best to install the new system; – –when is the best time to train users how to use the new system; & – –when will the new system be ready for use/delivery.

11. Project Planning Importance of Project Planning – –Project planning involves dividing the project into smaller tasks that are allocated to teams. The project leader must use the available resources in the best possible way to get the job completed successfully and on time. – –Project management software will organise the project into smaller tasks and then schedule these tasks. The schedule can be displayed as a Gantt Chart or a PERT Diagram. As the project progresses and jobs are completed or delayed, the charts can be updated to show the current position. – –In this way, the progress of a project can be monitored regularly.

12. Project Planning Elements in a Project Plan – –A project plan must show: the individual tasks that must be carried out the time required for each task the sequencing of the tasks to be carried out the resources needed for each task the costs involved in carrying out each task – –Typically, project planning methods show the tasks that must be carried out, the time required for each task and the sequencing of the tasks but they can both be used to show the resources needed for each task and costs involved.

13. Project Planning A Gantt chart is a form of bar chart depicting the timings of different tasks. – –It can be used to monitor progress throughout the project by showing which tasks have been completed at a certain date. – –A Gantt chart clearly shows the start date and finish date of major tasks. – –Deadlines for individual tasks are clear and time demands are easily identifiable.

14. Investigation Techniques ObservationObservation – –Observation involves watching the existing system in use and taking notes on how the system operates and functions. – – Observation often proves useful in gathering information in situations that clients take for granted. The analyst will be able to note the flow of work and the levels of normal and peak workload. – –Problems: One of the problems in using observation as an information gathering technique is that it is extremely time consuming. The analyst must also remember that it can be very difficult to observe users of a system without intruding on the normal work patterns. Most people find it difficult to ignore the fact that they are being observed and, as a result, find it difficult to carry on as normal.

15. Investigation Techniques Document SamplingDocument Sampling – –Documents are very important because they represent the flow of information within in the existing system. Each document will have its own cycle of creation, amendment, use and deletion. – –The sampling of company documents will lead to the discovery of details such as: the source of each data item the meaning, size and format of each data item the use made of each data item –Problems Documents missingDocuments missing

16. Investigation Techniques InterviewsInterviews – –An interview is planned and has a specific purpose. It consists of asking and answering questions and has a feedback mechanism. Interviewing is also the most common fact finding method and has to be conducted with the full co-operation of all employees. – –Problems People being absent can make this process time- consuming.

17. Investigation Techniques QuestionnairesQuestionnaires – –A questionnaire is a document that contains a set of pre- printed questions that have been carefully designed to measure a particular aspect of the existing system. – –Questionnaires are issued to several users of the existing system. – –Unfortunately, questionnaires have several drawbacks: they often have low response rates the lack of contact with the analyst may mean that questions are misinterpreted there is no opportunity for the analyst to observe users at work

18. Results from investigation As a result of gathering information about the existing information system, the analyst should now be able to: – –provide background information about the system; – –describe departmental objectives; – –describe all components in the existing system; & – –describe procedures within the organisation.

19. System Specification Once the analyst documented the existing system and presented his/her findings to the client. Having reached agreement with the client about the details of the existing system, the analyst can then start to prepare the System Specification. The System Specification is based on the findings from the investigation and modelling techniques used to confirm facts. Essentially, the System Specification is a document that outlines: – –the functional requirements of the replacement system – –any restrictions on the development of the replacement system.The System Specification describes all processes to be carried out by the replacement system. It will state the data elements that are necessary in the system and their storage requirements..

20. System Specification The System Specification will describe the outputs that the system is required to produce and identify any constraints placed on the system - for example, the new system may have to be compatible with other systems and files already existing in the business. The analyst again will make use of modelling tools to prepare the System Specification. These will enable him/her to describe what the proposed system should do without having to specify how the processes should be implemented.