System Analysis: Systems Analyst, System Design, Designing user interface

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Information System (CS507)

LESSON 22

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.

22.1 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

Information System (CS507)

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.

22.2 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.

22.3 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

Information System (CS507)

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 pre-

defined procedures every time around without any change unless an error has been caused to

the program handling the data.

22.4 Designing user interface

The design of what the user sees on the screen, that is, the interface, while entering data should be such that

Information System (CS507)

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

Information System (CS507)

LESSON 23

Benefits of Good System Design

Better understanding by the developer of the system. A properly designed system helps in

elaborating and understanding refined aspects of system.

System development becomes efficient. An error free designed system saves development time

since it helps in understanding without discussion.

A well designed system also helps in early detection of problems in critical areas, if any.

Better quality of reporting formats. Modifications can be made easily in the system.

Little maintenance is required in the operations phase.

23.1 System Analysis & Design Methods

Two approaches are followed for system analysis and design

Structured analysis and design Which includes various tools, such as.

Flowcharting

Data Flow diagram

ERD

Object oriented analysis and design

23.2 Structured Analysis and Design

Structured analysis and design follows a set of good practices and generally accepted standards. Proper

documentation of the system is made by following standard rules.

23.3 Flow Chart

"A schematic representation of a sequence of operations as in a manufacturing process or computer

program."

Introduction

Flowchart is the most commonly used design and analysis technique. The diagrammatic presentation gives a

quick understanding of the business processes and flows.

Symbols

Although there are many symbols used proposed by various standards, but we would discuss some of the

most commonly used symbols. Understanding symbols representing functions, flows, etc may be more

readily understood by those who have some knowledge of the symbols. From a technical or academic point

of view, we have to know what symbols are used for various functions, etc.

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