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Lesson#22
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System Analysis
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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.
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
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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
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•
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:
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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.
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
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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:
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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 |
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