CS507 - Information Systems - Lecture Handout 22

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System Analysis

System analysis can be defined simply as: “The study of business problem domain to recommend improvements and specify the business requirements for the solution.”

Or alternatively as:

“A problem solving technique that decomposes a system into its component pieces for the purpose of studying, how well those component parts work and interact to accomplish their purpose.”

Both the definitions highlight following important points:

  • System analysis helps to create an understanding of the business processes, their linkage with one another, the parameters governing the data flow within the business, the controls and checks built into the processes and the reporting needs in a business where a problem exists or for which the software needs to be designed.
  • System analysis creates the understanding and lays out the necessary relationships that will assist in defining a solution to the problem or the design of the proposed software that will meet the user needs.

These two points may be understood as providing a means for undertaking the following tasks:

  • A technique to map the system under study.
  • To drill down into the various aspects of the business process without losing sight of the complete system.
    • To understand the Workability/Functionality of the subsystems and their role in achieving the
      objectives of the system as well as controls and checks in place.
    • To establish the relationship or Level of interaction of each system with other components of the system.

Computerized vs. Manual environment

Information systems are designed and developed for both types of environments. System analysis is done in both situations covering business processes and flow of documents which include:

  • Documents being prepared to record transactions
  • Point of Origin of the data and documents
  • Who is responsible for originating
  • Destination/filing point/ultimate storage
  • Relationships between various divisions of the business in terms of data being received and recorded from different transactions, financial and non-financial
  • Controls devised to ensure accuracy, integrity and reliability of data
  • Reports generated, frequency and distribution thereof to various users

The difference between the manual and computerized environment arises due to the following reasons, quite simply because of the different nature of the environments:

  • Logical access control issues in computerized environment.
  • Duplication of clerical work generally observed in a manual environment is eliminated in the computerized environment.
  • Automatic generation of specified reports: In a computerized environment as opposed to manual data compilation.
  • Data integrity is more fully secured in a computerized environment with addition or authorized changes in data being automatically updated for all purposes through a single button effort as opposed to making changes or updating in each register or record affected by the same in a manual environment.
  • Drill down function to conduct analysis of recorded data is available in a computerized environment as opposed to undertaking a manual analysis of all data.
  • Flexibility of presenting data in desired or different format including using specified data to be shown graphically is available in computerized environment.
  • Data Security and confidentiality can be assured to a higher degree in a computerized environment.

Systems Analyst

“These are knowledge workers who facilitate the development of information systems and computer applications by bridging the communications gap that exists between non-technical system users, and System designers and developers.”

Why do we need Systems Analysts?

Systems analysts work as a link between Business people, & Computer Programmers. Business People may define the business to be computerized, i.e. establish scope of computerization. However, they may not fully understand the capabilities and limitations of modern information technology.

Computer programmers apply information technology to build information systems which solves these problems but need not fully understand the business usages they are computerizing or supporting.

Systems Analysts due to their expertise in development, knowledge of business processes, awareness of industry best practices, bridge the gap by translating the scope of computerization into how the systems will handle the transactional flows and the relationship between the various aspects of the business for the programmers whilst keeping the overall objectives and requirements, both corporate and IT related in perspective.

System Design

System Design maybe defined as “A problem solving technique that re-assembles a system’s components back into a complete system. This may involve adding, changing deleting pieces relative to the original system” or alternatively as “the process or art of defining the hardware and software architecture, components, modules, interfaces, and data for a computer system to satisfy specified requirements.”

Once the existing system is analyzed and user requirements established they need to be either incorporated into the existing computerized system or assist in the development of a new system.

The major components of system design are:

  • Designing usable and complete input
  • Designing well defined and usable output with flexibility to redefine presentation of outputs in any form.
  • Designing file or database
  • Designing user interface (input screen as it would be seen by the user)

Designing usable and complete input

This includes the design of input forms to record data. The input forms should be accurate, easy to use, consistent and simple. Preferably the input forms should not differ too greatly from the manual input forms being used by a business, as this can help in the change management process. All Primary parameters pertaining to the various input forms must be defined as part of the input design e.g. basic information pertaining to various entities suppliers, customers, employees and chart of accounts. There are cases where the definitions were incomplete resulting in an inability to produce a report on the basis of an undefined parameter. Thus great care and diligence is required when undertaking this task.

Designing well defined output

Various considerations need to be kept in mind while defining parameters for desired output. These should generally focus on:

  • Assuring purposeful output
  • Providing output as defined and required by users
  • Providing appropriate information
  • Assuring distribution of output as per client specified requirements.
  • Minimizing throughput time and Query time.
  • Ensuring that output is available in client required mode.

Many business managers due to lack of knowledge are not able to visualize their future reporting needs or even define the end to end output requirements or linkages as they assume that these will be produced magically by the computer. Unfortunately, the unexpressed wishes cannot be turned into reality unless someone at the design and development stage had specified these needs and the same have been accordingly parameterized. In situations where this is not done output designing becomes an open ended process, which is neither time or cost beneficial for the organization.

Designing file or database

This serves following purposes:

  • Data accessibility is ensured to the user is ensured as and when required.
  • Data consistency – data updates in master file will automatically update the data in the whole system.
  • Data is efficiently processed & stored.
  • Data integrity that is Correctness of data is ensured. This does not mean that incorrect amounts entered into the computer will be automatically corrected by because the computer only records what is entered but if there is an error in entering pre-defined parameters these would be corrected or thrown up as an error. Further, the data processed according to the predefined procedures every time around without any change unless an error has been caused to the program handling the data.

Designing user interface

The design of what the user sees on the screen, that is, the interface, while entering data should be such that the user is familiar with. The information should be entered in a logical sequence e.g., if a user wants to add an employee to the employee’s master file, the information may be entered in the following sequence:

  • Employee ID, which can either be
    • Generated automatically by the system, or
    • Entered manually by the user
      • Name
      • Address
      • Contact information
      • Next of kin
      • Grade
      • Designation
      • Salary Details