UNIT 1
INFORMATION, MANAGMENT AND SYSTEMS
DATA AND INFORMATION
Data
Data is the collection of raw facts about an object, people, places and events which when
processed or manipulated makes meaningful output. Data consists of raw and unanalyzed facts
and figures that are relatively meaningless to the user. Data also represents convenient way of
storing and communicating the essential attributes of an entity. Data are fairly useless unless
some information can be extracted from it.
Information
When data are processed, organized, structured or presented in a given context so as to make
them useful, they are called information. Information is also described as data that has been
processed in some manner into a form that is both usable and meaningful to the end user.
Information therefore, is data that has been organized and communicated in a form convenient
for human decision-making.
One of the distinguishing features between data and information is its usefulness. The value of
information lies solely in its ability to affect a behavior, decision or outcome. A piece of
information is considered valueless if, after receiving it, decisions the information is supposed
to influence remain unchanged.
The truth is that both data and information are highly subjective. Information in one instance
may be data and vice versa, that is why it is sometimes difficult to differentiate between them.
Data and information can best be explained within the context in which they are used.
Difference between Data and Information
The difference between Data and Information are not only limited to the table below:
DATA
INFORMATION
Letters, numerals, and characters are used The format of information is either
to represent data.
thoughts or references
Graphs, data trees, flowcharts, and tables
are all used to organize data
After compiling the data, the information
is represented as ideas, concepts, and
languages.
Data is useless until it is further expanded When data is interpreted and a meaning is
derived from it, it becomes information.
Variables, both qualitative and
quantitative, that have the potential to be
developed into ideas or analytical
conclusions
Data that has been formatted and compiled
in order to improve its meaning and
contextual utility.
Data is information that has been gathered When data is interpreted and a meaning is
derived from it, it becomes information
Data isn't enough to make decisions; it
must be combined with other factors.
Analytical coherence is present in the
information which aids in the decisionmaking process.
Table1.1: Differences between data and information.
Process
Before data is transformed into information, it undergoes series of manipulation based on the
requirements of the user. This manipulation is also known as process or transformation. The
processing phase is usually automated and facilitated by the use of computer hardware and
their associated software.
Data (Input)
Process
Information (Output)
Figure 1.1: Data transformation process
Characteristics of Information
Not all information can be considered as good information. Good information is one that is
used to affect decision and which creates value. Experience and research show that information
has high value if it has the following qualities.
Timely: Information must be available when it is required. Information received too late is
irrelevant. For example, if you receive a report that there was demand for your product
yesterday, the information may be too late to be of use today.
Accuracy: Accuracy means information is devoid of errors. Information should provide
reliable and correct representation of what is needed. The effect of inaccurate information is
very disastrous for organizations’ decision-making purposes.
Clarity and Concise: Good information is one that is clear, simple, precise and unambiguous.
Clarity and conciseness also means the information should be devoid of ‘noise’ or extraneous
details.
Relevance: The information at hand should be important and significant for the purpose for
which it is meant. Relevant information is one that is significant and can be applied to solve a
specific problem. Irrelevant information has bad consequences for a decision maker.
Trustworthy (Reliable) Source: For information to be useful for decision-making, it must
come from dependable source so that users can have confidence in it.
Completeness: Information should contain all the details required by the user to take decisions.
Information should be comprehensive enough to give a complete picture of what it represents.
For example, in fashion business, information about your customers will be incomplete without
their gender since it will enable decision makers know which of the genders’ goods are in
demand.
Availability/Accessibility: Information should be available and accessible to its authorized
users irrespective of the location of the information or the users. In this age, the Internet greatly
facilitates the availability and accessibility of information.
Cost/Economical: Cost incurred in producing information should be economical such that an
organization is not unduly over burdened with expenses. The intrinsic value of information
should be more than the cost associated with producing a given information. Information is
uneconomical if it takes more revenue from the organization than it brings into the
organization. Information therefore should be produced within the cost constraint of an
organization.
OUTPUT OF INFORMATION
Information systems process data (input) from transaction systems into information (output)
for management decision purposes. Output of information can be reports, graphs, sound, video
etc. In most information systems, reports are the primary means by which information are
presented to users. Reports which may take one of the following forms are classified according
to how often, how detailed, or the purpose for which they are used, among others:
• Periodic Reports/Scheduled Report.
• Key Indicator Report.
• Demand Report.
• Exception Report.
• Special Report.
• Predictive Report.
• Drill Down Report.
• Trend Report.
Periodic Reports: Periodic reports are reports that are produced at a regular time interval such
a daily, weekly, monthly, annually, etc. For instance, in most organizations, payroll reports are
produced quarterly or monthly. Periodic or scheduled reports for example enable managers to
monitor the sales performance regularly.
Demand Reports: Demand reports are reports that are produced or given when they are
requested for by management. In other words, unlike periodic reports, these reports are
produced on demand. The content of the report depends on the circumstances and the person
requesting for the report. For example, a sales manager can at anytime demand sales
information about some product to aid him or her take decisions.
Exception Reports: These are reports that are automatically produced or triggered off when
something extraordinary that needs immediate attention happens. For instance, an accountant
may want the payroll information system to produce an exception report if an employee’s net
salary is a negative amount. In such a situation, the programmer will set a trigger in the
information system so that a report is automatically produced when such a situation occurs.
Timely reporting of exception situations make it easier for a manager to separate a problem
and attend to it.
Predictive Reports: These are forecasting reports that are produced by an information system
based on analysis of historic and present data. Predictive reports enable organizations to plan
for the future. Some typical predictive reports of interest to an organization are predictive sales,
organization’s budget, etc.
Key-indicator Reports: Key-indicator report provides a summary of critical information on
an event or transaction. This report summarizes inventory levels, sales volumes, and production
activity. It is used for managers and executives to take quick remedial actions on significant
aspects of the organizations.
Drill Down Reports: Drill down reports produce more detailed data about a situation of
interest.
Trend Reports: Trend reports enable a manager to compare the performance of some aspects
of the organization or product. For example, a manager may request for sales information of a
product on monthly basis in the current year and compare it to sales of the previous year.
CLASSIFICATION OF INFORMATION
Depending on the way users see information, it can be classified into many forms. Some of
them are discussed below:
Framework within which Data is generated
From the framework within which data is used or generated, data can be classified as follows:
International: This is information that originates outside the boundaries of a country but that
have implications on an organization. In business for instances, prices of world crude oil, stock
exchange prices, wars, natural disasters, change of government in a country may all have
implications on an organization that does business with the country where these information
originated.
National: It is information that originates within one’s country and that has consequences for
organization/business. These can be foreign exchange rates, inflation, interest rate, minimum
wage rates and age distribution.
Corporate: This is information that is generated within the business level, and that influences
management decisions. These can be corporate rules and policies, gender of employees, health
status of employees, age distribution of employees etc.
Departmental: Departmental information is a subset of corporate information. It is
information of specific interest to a department within an organization. This can be specific
information that originates or is applicable to a department within an organization.
Individual: Individual information are the bio-data and other information about the employees
who constitute the working force of the organization. These can be the gender ratio, age
distribution, health status etc.
By Business Categorization
Strategic: These are information that are required by top management to facilitate decisionmaking that affect the fortunes of the organizations. Those decisions are long term in nature,
novel and mainly for planning purposes.
Tactical: They are the information that are needed by middle management to aid them carry
out the objectives or decisions that have been set out by strategic managers.
Operational: Operational managers need routine information, for example, about sales, in
order to know the quantity of goods they have to produce and where to market them. This can
be referred to as operational information.
By Time
Past: Past information are the historic information about organizations’ operations. They are
important to enable organizations to know how far they have come, and they assist them to
predict where they are heading. Also, laws make it mandatory for organizations to keep for
example, their accounting books for some number of years before they can dispose of them.
Present: Information that relates to the current operation and transaction of an organization.
Future: These are predictive information, and they are usually projected information that
management use to take decisions. Future information are projected from the past and present
information.
By Quantifying
Quantitative: These are measurable, quantifiable information about activities, events, and/or
behavior that the organization tracks as measures of progress toward the achievement of their
objectives.
Qualitative: Descriptive information are about activities, events, and/or behavior that the
organization tracks as a measure of progress toward objectives. Qualitative information focuses
on observations, through such techniques as interviews, document analysis, focus groups or
reviews by stakeholders.
By Source
Primary: Primary sources are the first hand evidence recorded by participants or observers at
the time of events. It is the original work of research or raw data without interpretation that
represents an official opinion or position. Proceedings of meeting, speeches and transactions
are examples of primary source.
Secondary: Secondary sources are materials that digest, analyze, evaluate and interpret
information contained within primary sources. Secondary sources take primary sources and
interpret them. Textbooks, history books, annual business reports, other reference materials
and sales analysis reports are all examples of secondary sources. Secondary sources are
compiled by using primary sources. They have credibility, but they are not as strong as primary
sources.
Tertiary: These are materials in which the information from secondary sources has been
organized - reformatted and condensed, to put it into a convenient way to use. Dictionaries,
encyclopedias and fact books are considered as tertiary sources.
MANAGEMENT AND DECISION-MAKING
Introduction
Management is the different functions managers undertake to get tasks accomplished
successfully, and it is required in every establishment. Decision-making is the process
managers go through to make decisions, and it is a core role for every manager. Management,
information systems and decision-making are interrelated because management uses
information systems to facilitate their decision-making functions. In this section, we shall
deliberate on management and decision-making.
MANAGEMENT
What is Management?
The term ‘management’ encompasses an array of different functions undertaken to accomplish
a task successfully. It is the way and the process of how one achieves one’s target or goals and
it is in this respect that management is considered an art and a science as well. In the simplest
of form, management is all about ‘getting things done through and with people” (Mary Parker
Follet).
Management therefore is the act of getting people together to accomplish desired goals and
objectives using available resources efficiently and effectively. Management comprises
planning, organizing, staffing, leading or directing, and controlling an organization or effort
for the purpose of accomplishing a goal.
Some Established Definitions of Management
• “Art of knowing what you want to do and then seeing that it is done the best and
cheapest way.” (F.W. Taylor).
• “To manage is to forecast, to plan, to organise, to command, to co-ordinate and to
control.” (Henry Fayol).
• “Management is work and as such it has its own skills, its own tools and its own
techniques.” (Peter F. Drucker).
• “Management is the art of getting things done through and with people”
(Mary Parker Follet).
• "Management is the art of getting things done through and with the people in
formally organised groups." (Horold Kanontz).
• "Management is a distinct process consisting of planning, organising, activating and
controlling to determine and accomplish the objectives by the use of people and
resources." (G.R. Terry).
Characteristics of Management
a. It is a process.
b. It involves group effort.
c. It aims at achieving predetermined objectives.
d. It is required at all levels of management.
e. It is a profession.
f. It is an art and science.
g. It is comprised of some of the following functions: planning, organizing, staffing,
directing, controlling, coordinating and budgeting.
FUNCTIONS OF MANAGEMENT
While other management experts may use different words and focus on different aspects, the
following are the generic functions of management:
Planning
Planning involves looking ahead and charting out future course of operation. In the course of
performing their planning function, managers analyze the current situation, anticipate for the
future, determine, formulate objectives, policies, procedure, rules, programmes and budgets so
that they can accomplish what they intend to do. Planning, thus is mapping out how to achieve
a particular goal.
Organising
Organizing is bringing people and other resources together and tying them together in the
pursuit of common objectives. It entails enumeration of activities, classification of activities,
assigning job responsibilities, assignment of authority for action, resource allocation etc.
Organizing is therefore the assembling and co-ordination of various types of resources to
achieve organizational goals.
Directing
It is the act of guiding, overseeing, motivating, instructing and leading people in an
organization. Directing ensures that organizational staffs work in unison so that organizational
objectives can be achieved.
Controlling
Controlling is the management function of monitoring progress and making needed changes to
ensure that the organizational goals are achieved. Its activities include setting standards,
monitoring performance, comparing standards against actual and correcting deviations.
Coordinating
Managers coordinate by making different people and business activities work together to fulfill
desired organizational goals. Coordinating involves synchronizing and unifying the actions of
a group of people as well as procedures and activities performed by an organization.
Staffing
A manager’s staffing function entails recruiting, orienting and training of people for specific
job functions and charging them for particular responsibilities. A manager may liaise with the
organization’s human resource department in the execution of this function.
Communicating
A manager’s communicating function is the process of transmitting information, ideas,
thoughts, opinions and plans between various parts of an organization. A manager superintends
over all the units that fall under his or her authority, and it is the communication role that keeps
those to whom a manager is responsible informed.
Budgeting
A budget is an overall financial plan that reflects an organization’s goals and objectives for a
period. A manager budgets by making financial plans and forecasting, maintaining accounting
and management control of revenue, and keeping costs in line with objectives.
Leading
Leading is the management function that involves the manager's efforts to inspire high
performance of employees. It involves directing, motivating and communicating with
employees, individually and in groups.
LEVELS OF MANAGEMENT
Generally, most organizations have three management levels: First line-level (operational
management), Middle-level (tactical management) and Top-level (strategic management)
managers. These management are classified in a hierarchy of authority, and they perform
different tasks.
Top Level
Management
Middle - Level
Management
First - Level Management
Figure 1.2: Levels of management
First-Level Management
First-level managers are also called first-line managers, operational managers or supervisors.
These managers have job titles such as: Office manager, Shift supervisor, Department manager,
Foreman, Store manager.
Operational managers are responsible for the daily management of the employees who actually
produce the product or offer the service. There are first-line managers in every work unit in the
organization and they may report major problems to tactical managers for decisions. Although
operational managers typically do not set goals for the organization, they have a very strong
influence on the company. Operational managers interact with most employees on a daily basis
and if they perform poorly, employees may also perform poorly, may lack motivation or may
even leave the organization.
Middle-Level Management
Middle-level management or tactical management are those in the levels below top managers.
Middle level managers may have job titles such as: General manager, Plant manager, Regional
manager and Divisional manager.
Middle-level managers are responsible for carrying out the goals set by top management. They
do so by setting goals for their departments and other business units in line with those set by
top management. Middle managers motivate and assist first-line managers to achieve business
objectives. Middle managers may also communicate upward by offering suggestions and
feedback to top managers. Because middle managers are more involved in the day-to-day
workings of a company, they provide valuable information to top managers to help them in
their strategic decision-making.
Top-Level Management
Top-level management or strategic management, is also called senior management or
executives. These individuals hold titles such as: Chief Executive Officer (CEO), Chief
Financial Officer (CFO), Chief Operational Officer (COO), Chief Information Officer (CIO),
and Chairperson of the Board, President, Vice president, and Corporate head.
Top-level managers make long-term strategic decisions affecting the entirety of the firm. Top
managers do not direct the day-to-day activities of the firm; rather, they set goals for the
organization and direct the company to achieve them. They make decisions regarding the
resources to use to attain the objectives. Top managers are ultimately responsible for the
performance of the organization. Top managers in most organizations have a great deal of
managerial experience.
INTRODUCTION TO MANAGEMENT DECISION-MAKING
What is Decision Making?
Decision-making is the process of choosing the best alternative to reach a set objective. Every
manager makes decisions that affect the running of the organization. These decisions are then
communicated to members of the organization. The need to take a decision may arise due to a
threat or an emerging opportunity an organization needs to take advantage of.
Taking of decisions is an indispensable part of management and it takes place at all levels of
management. Decision-making is dependent upon making the right information available to
management at the right time. Though the nature of decision-making varies from manager to
manager, decision makers go through almost the same process.
TYPES OF DECISIONS-MAKING
Programmed Decision-making
It is also known as structured decision-making. Programmed decision-making can be taken
objectively because a manager has taken that decision before or there are generally clearly
defined methods, rules and guidelines to follow to solve a problem. Some characteristics of
programmed decisions are that they are repetitive, routine, known decision rules or procedures,
and can be automated.
Non-Programmed Decision-making
This is also known as unstructured decision-making. This sort of decision is highly subjective
because the outcome cannot be predetermined. It is normally an unusual situation that has not
been addressed before. There are no formal rules to use to solve non-programmed decisionmaking and managers use information, their intuition and judgment. Non-programmed
decision-making exhibits the following characteristics: novel, non-routine, high degree of
uncertainty, decision rules are not known.
Semi-structured Decision
They lie between structured decision and unstructured decision. With this, solutions are known
for some part of the problem (structured), and for some part, solutions are not known
(unstructured).
Heuristic Decision
There are no guidelines or set of rules that tell managers exactly how to make a decision.
However, people use heuristics to aid in their decision-making. Heuristics is based on trial and
error, previous experience, guessing, probability, etc. Heuristics do not always produce a
correct answer, and sometimes they are the reasons why people make the wrong decisions.
SYSTEMS
A collection of components that work together to realize some objectives forms a system.
Basically there are three major components in every system, namely input, processing and
output. In a system the different components are connected with each other and they are
interdependent. For example, human body represents a complete natural system. We are also
bound by many national systems such as political system, economic system, educational
system and so forth. The objective of the system demands that some output is produced as a
result of processing the suitable inputs. A well-designed system also includes an additional
element referred to as „control‟ that provides a feedback to achieve desired objectives of the
system.
Definition of System :
A system is an orderly grouping of interdependent components linked together according to a
plan to achieve a specific objective.
According Lucey (2005), Open University defines a system as an assembly of parts where:
•
•
•
The parts or components are connected together in an organized way.
The parts or components are affected by being in the system (and are changed by
leaving it).
The assembly does something.
•
The assembly has been identified by a person as being of special interest.
The above definition suggests that a system is a group of interacting components with a
purpose. Business and social systems handle, process, manipulate inputs/resources to produce
outputs of goods and/or services in order to fulfill the objectives of the organization.
Examples of systems are university, hospital, an accounting system, a manufacturing
company, information system and transportation system.
Characteristics of a System:
i. Organization-It implies structure and order.
ii. Interaction-It refers to manner in which each component functions with other components
of the system.
iii. Interdependence-Units/parts are dependent on each other.
iv. Integration-The parts of a system work together within the system even though each part
performs a unique function.
v. Central Objective-Objective may be real or stated. All the components work together to
achieve that particular objective.
Features of the Systems
Lucey (2005) identified the following as the features of the systems approach:
a. All systems are composed of inter-related parts or sub-systems and the system can only
be explained as a whole. This is known as holism or synergy. Holism states that any
whole is more than the sum of its individual parts. This means the whole is not just the
sum of the parts; but the system itself can be explained only as a totality.
b. Systems are hierarchical in that the parts of systems are made-up of other smaller parts
(sub systems). The system itself could be part of another bigger system known as supra
system. A complex system is difficult to comprehend when considered as a whole,
therefore, the system is decomposed or fractured into sub system. The sub systems
resulting from process of decomposition generally form hierarchical structures.
c. The parts of a system cannot be altered without affecting the other parts of the system.
This means that in an organization setup for instance, decisions that a manager takes
within his or her unit naturally will have effect on other departments within the
organization and vice versa.
d. The sub-systems should work towards the goal of their higher systems and not pursue
their own objectives independently. Where sub-systems do pursue their own objectives
to the detriment of the objectives of a higher subsystem, then a condition of suboptimality is said to exist.
e. Organizational systems are composed of both hard and soft properties. Hard properties
are those that can be assessed in some objective way, an example is the number of items
a business produces per day. The soft aspects of a system are a matter of individual
values or taste. They cannot be assessed by any objective standard or measuring
process. With soft properties, organizations are unsure of what solution would look
like. An example of soft aspects of an organization decision-making is the suitability
of a person for a job.
THE ELEMENTS OF A SYSTEM
The basic elements of a system are: Input, Output, Transformation process, Feedback, System
boundaries and Environment of a system.
Input
Input varies from system to system. In an application software input may be data, whereas in a
manufacturing firm, inputs may be raw materials, labour, equipment and plants, power supply
that are to be transformed by processes to achieve the finished product
The Transformation Process
The processes are the methods, developments, practices and procedures that are used to
transform or convert the inputs into the desired outputs. In social systems, the transformation
process is controlled or influenced by information.
Output
Outputs are the end products of the process. Systems return output to the environment. Similar
to input, output differ from system to system. The output of application software is likely to be
information in the form of a report to facilitate management decision-making and that of a
manufacturing enterprise is the finished goods. In reality, organizations choose those outputs
that we are concerned with. These are usually those outputs most relevant to the system
objectives. Those outputs such as waste and noise are neglected.
Feedback
The concept of feedback is important in understanding how a system maintains a desired state.
Information concerning the outputs or the process of the system is fed back as an input into the
system, perhaps leading to changes in the transformation process and/or future outputs.
Feedback is used to monitor system and guide it to a desired performance.
Feedback can be both positive and negative. Negative feedback is information that indicates
that the system is deviating from a prescribed course and should readjust to a new desired state.
Feedback
Input
Process
Output
Figure1.3 : The concept of feedback
System Boundaries
Boundaries are features which define the extent of a system. In mechanical, physical and
biological systems, it is relatively easy to establish boundaries. With respect to social
organizations, boundaries are not clear, highly dynamic in nature, often change to meet
differing demands and difficult to establish. Within organizations, boundaries are determined
by management and vary from organization to organization.
The boundaries of systems separate them from their environments. The concept of boundaries
therefore gives rise to open and closed systems and also helps us to understand the distinction
between them.
The Environments of Systems
All elements not in the system, that is, all elements outside of a system constitute the
environment of a system. But specifically, environments are the external elements whose
changes in attitudes, behavior or properties affect the state of the system and those external
elements which are changed by the system’s behavior. The environment of a system is very
diverse and not static. Examples of organization’s environments are customers, competitors,
suppliers, technology, government policies and influences. It must be mentioned that not all
environmental factors can be influenced or controlled. Changes in environment directly affect
the structure and function of the organization. Although some factors in the environment cannot
be controlled, for example, the weather, organizations do attempt to influence their
environment. For example, businesses advertise their products to create and encourage
demand.
Organizations that regularly exchange feedback with their external environment are known as
open system. Such organizations try to study and understand their environments through the
use of environmental scanning, market research and evaluations. Organizations use public
relations, advertising, promotion, lobbying etc. to influence the environment.
CLASSIFICATIONS OF SYSTEMS
There are several ways of classifying systems. Two such classifications of systems are based
on:
a. Their degree of interaction with the environments. The way an organization relates
to changes in its environment is important to its success. This results in systems
being classified as Open System or Close Systems.
b. Their predictive behavior. With respect to this, a system is classified as
Deterministic System, Probabilistic system or Self-organizing/Adaptive Systems.
Closed Systems
A closed system is one that is isolated from its environment. A closed system does not interact
with the environment, it does not take input from the environment, and neither does it give
output to the environment. A closed system does not recognize that it is embedded in a relevant
environment. Changes in the environment and adaptability are not issues for closed system.
Closed systems are entirely focused on internal functions and behaviors. Closed systems do
not use feedback appropriately. Organizations that have closed boundaries are often unhealthy.
The concept of closed system can only strictly be applied to mechanical and physical systems,
as all social systems have some interactions with their environment.
Manufacturing systems as an example are designed to be as closed as possible so that the
manufacturing process can operate without disturbances from suppliers, customers, etc. A
computer program is a relatively closed system because it accepts only previously defined
inputs, processes them and provides previously defined outputs.
Closed System
No interaction
with the
environment
Figure 1.4: Closed System
Open Systems
An open system has many interfaces with its environment and exchanges feedback with them.
Open system interacts freely with its environment, taking input and influences from the
environment and returning output and influences to the environment. Open system thus permits
interaction across its boundary. Healthy open systems exchange feedback with their
environments, analyze that feedback, adjust internal systems as needed to achieve systems’
equilibrium and then transmit necessary information back to the environment.
Open systems have form and structure to allow them to adapt to changes in their environment
in such a way as to ensure their continue existence. They are self-organizing and self-regulating
in the sense that they change their organization systems in response to changing conditions or
adapt and react to inputs or stimuli. Biological Living systems (cells, plants, humans) and social
organizations are open systems. The way that organizations adapt to changes in the
environment is a key element in an organization’s success and indeed its very survival.
En
v
i
r
o
n
m
e
n
t
Exchanges and
interactions with
the environment
E
n
v
i
r
o
n
m
e
n
t
Figure 1.5: Open System
Deterministic Systems
These are predictable systems
where output can be predicted from input. The
interactions between the parts are known with certainty. Example is a machine producing a
component where the units of output can be determined from the inputs.
Probabilistic or Stochastic Systems
This is where some conditions of the system can be predicted from the previous state but only
in terms of probable behaviour. There is always a certain degree of error attached to the
prediction of what the system will do. For example in a sales information system, the average
sales can be predicted, but the exact value cannot be predicted.
Self-organizing or Adaptive System
These are systems that spontaneously react to input or stimuli. With these systems, the results
of the change cannot be predetermined, as the same input will not necessarily translate into the
same output.
.Shared and Overlapping Sub-Systems
Sub-systems can belong to more than one system and there is a need to recognize this overlap
and design operations and processes accordingly. The recognition of overlap is particularly
important when changes are made in one of the systems which share the same sub-system.
Overlap is often an efficient and economical arrangement. For example, a central purchasing
sub-system used by various departments within an organization may be able to obtain greater
discounts and may also aid the standardization of parts and materials. A centralized computer
facility may be shared by all departments within an organization with a reduction in overall
costs.
However shared and overlapping subsystems are likely to result in communication difficulties
and may have longer response times. Because of the need to co-ordinate activities and to obtain
numerous approvals for change, such structures may be less flexible in rapidly changing
conditions (Lucey, 2005).
Supra-System
A supra-system is a macro level system composed of a number of subsystems. The individual
units forming a system are typically called subsystems, elements or components, and the
larger composite enclosing a system is called the supra-system.
Information System as a System
Information system is a system by definition, as it is made up interrelated components that
come together to convert data into information. These interrelated parts or components or
subsystems have structure, for example, hardware and noticeable behavior such as software.
Others are personnel, networks/telecommunication equipment, database and procedure.
INFORMATION SYSTEMS
What is information system?
Information System is a set of interrelated components that collect, manipulate, store and
disseminate data and information and provide feedback mechanism to meet an objective.
Laudon and Laudon (2000) put it “as set of interrelated components that collect (or retrieve),
process, store, and distribute information to support decision-making and control in an
organization. In addition to supporting decision-making, coordination and control, information
systems may also help managers and workers analyze problems, visualize complex subjects
and create new products.”
In general, information systems are established to support policies and or procedures in
organizations. Information systems accomplish these through a cycle of four basic activities:
Input, Process, Output and Feedback.
Input
In information systems, input is the activity of gathering and capturing data. In a student’s
information systems for instance, students’ assessments are captured by their lecturers before
their grade points average (GPA) can be computed. Input takes various forms depending on
the type of information systems. It may be numeric, alphabetic, images, signals from a device,
sound. The underlying requirement of any input is its correctness.
Processing
Processing is the act of transforming or manipulating the input into the desired output.
Processing may involve performing mathematical operations on the input, making comparisons
and taking alternative actions based on the outcome of the comparison.
Output
Output is the end desired results of processing input. A typical output may be in the form of a
report, for instance a pay slip for employees, report for management. An output of one
information system may serve as input for another information system.
Feedback
Feedback is output that is used to make changes to the input or processing activities. For
example, errors in the output will necessitate making changes in the input and/or the processing
activities.
Feedback
Data (Input)
Process
Information (Output)
Figure 2.1: Information systems processing cycle
Components of Information Systems
Being a system, an information system is comprised of some sub-systems, the main ones being
hardware, software, database, telecommunication equipment, people and procedure.
Hardware: Hardware consists of the physical computer equipment used to perform the input,
process, storage and output operations.
Software: Software are the programs that run the hardware. There are basically two main types
of software. The system software controls the operation of the computer itself and the
application software, which are the software that serves the specific need of the organization,
for example, a store inventory program.
Database: Database is an organized collection of facts and information. A business database
may contain current information about their employees, customers, sales information and
sources of raw materials. For databases to be organized, the organization will need
corresponding database management software.
Telecommunication Equipment: These are the networking equipment that facilitates the
transmission and sharing of data and information from one location to another. Today’s
Internet-based information system cannot be complete without telecommunication equipment
of a sort. This is because computers need to be networked and businesses are carried out via
Internet, extranet, intranet which are all connected by telecommunication equipment.
People: An indispensable component of information system is people. People develop,
manage, maintain, run and use the system. In a computer-based information system, there are
categories of staff who interface with the system differently.
Procedure: Procedures are the policies, rules, strategies and methods for using an information
system. Information system for organizations have these procedures that describe who gets
access to what, who run a type of programs, who and when to take a backup, what to do in case
of a disaster, etc.
Procedure
Telecom
Softwaree
Hardware
E
Personnel
Database
Figure 2.2: Components of information systems
TYPES OF INFORMATION SYSTEMS
Different levels of management perform diverse roles, hence the need for different types of
information systems to aid them in the performance of their roles. Generally, operational level
management utilizes transaction processing systems. Middle level management is aided by
management information systems and decision support systems and Strategic level is supported
by executive support systems. Office automation system facilitates the work of all the levels of
management.
Strategic
Management
EIS/ESS/OAS
Tactical
Management
Knowledge Workers
Operational Management
DSS/MIS/OAS
KWS/OAS
ESS/OAS
Figure 2-3: Types of information systems and the level of management
they serve
TRANSACTION PROCESSING SYSTEM (TPS)
A TPS is a basic business system, and it serves the operational management level. It collects,
stores and processes information about transactions as they occur in an organization. They are
used by clerks and other operational staff to capture and maintain data about the business of
the organizations, and control some aspects of transactions. A transaction is an event of interest
to the organisation, an example is sales made by a customer at the store. Some examples of
TPS are manufacturing and production systems, sales and marketing systems, finance and
accounting systems, human resource systems. Some characteristics of TPS include:
a.
b.
c.
d.
e.
f.
It serves the most elementary day-to-day activities of an organisation.
It supports the operational level of the business.
It supplies data for higher-level management decisions.
It is often critical to the survival of the organisation.
It is mostly suitable for predefined, structured tasks.
It can have strategic consequences for an organization (for example in airline
reservation system).
g. It usually has high volumes of input and output.
h. It provides data which is summarised into information by systems used by higher levels
of management.
Transaction Processing Methods
The basic transaction processing methods are:
On-line Transaction Processing: It is a transaction mode in which data is entered interactively
(online) into a system.
Batch Processing: In batch processing, data for all transactions to be processed are brought
together and processed in a group. This is normally done at regular intervals, such as hourly,
daily, weekly, fortnightly, monthly, quarterly, yearly etc. An example is a payroll system
which is run on monthly basis.
Real-time Processing: In this transaction mode, processing is also interactive, and the change
in the database occurs instantaneous as transaction occurs. An example is an airline reservation
system.
Hybrid Processing: It is a combination of some of the afore-mentioned methods.
Sub-Systems of TPS
Manufacturing and Production Systems: Systems that supply data to operate, monitor and
control the production process. For example, purchasing, receiving, shipping, process control,
robotics, inventory systems, scheduling, engineering, operations, quality control, resource
management, etc. For example, a system in a factory that:
a. Gets information from measuring samples of products.
b. Does statistical analysis of samples.
c. Shows when operators should take corrective action.
Sales and Marketing systems: Systems that support the sales and marketing function by
facilitating the movement of goods and services from producers to customers. Examples are:
a. Sales Support - Keep customer records, comments.
b. Telemarketing - Use phone for selling.
c. Order Processing - Process orders, produce invoices, supply data for sales analysis and
inventory control.
d. Point-of-Sale - Capture sales data at cash register often by scanner.
e. Customer Credit Authorisation - advise on credit to be allowed to customer. For
example, a store's sales system would automatically record and total purchase
transactions and prints out a packing list.
Finance & Accounting Systems: Systems that maintain records concerning the flow of funds
in the firm and produce financial statements such as balance sheets and income statements. For
example, Budgeting General Ledger, Billing, Cost Accounting, Accounts Receivable/Payable,
Funds Management Systems, Payroll, Cash Management, Loan Management, Check
Processing,
Securities
Trading.
Human Resources System: Systems that deal with recruitment, placement, performance
evaluation, compensation and career development of the firm's employees. Examples are
personnel record keeping, applicant tracking, positions, benefits, training and skills
developments.
OFFICE AUTOMATION SYSTEM (OAS)
OAS provides facilities – software, hardware and communication equipment that capture,
process and distribute data and information in an organization. Typical office automation
system handles and processes documents with the aid of word processing, spreadsheet,
presentation packages, desktop publishing, document imaging, file managers, scheduling and
communication
with
email,
video
conferencing.
OAS, thus is a software that increases efficiency and productivity of data workers by providing
them access to basic systems such as communication system, word processing, spreadsheet,
presentation software, desktop publishing, document imaging, scheduling, etc.
Though, OAS serves mainly information needs of data workers, it is also used significantly
across all the strata of management. A data worker is one whose job leads to the generation
and processing of data and information in an organization. Examples of data workers are
cashiers, accountants, secretaries whose duties involve the generation, processing and
communication of data and information.
OAS Sub-systems
Communication System: It helps people work together by sharing information in many
different forms. These can be Teleconferencing (including video conferencing, computer
conferencing, and audio conferencing), electronic mail, voice mail, fax, Internet, LAN.
Groupware System: It helps teams work together by providing access to team data, structuring
communication and making it easier to schedule meetings. Groupware system also has tools
for sharing information, controlling workflows, communication and integration of work.
Desktop Publishing: It produces professional publishing-quality document by combining
output of word processing software with design elements, graphics and special predetermined
layout.
Word Processing: This is hardware and software that are used to create, edit and print
professional looking documents. Word processing probably is one of the most commonly used
applications of information technology in office work.
Document Imaging: Document imaging allows organizations to capture paper-based
information and convert it to electronic images that are stored in a computer electronically.
Some of the reasons why organizations do document imaging are: accessibility, security and
saving of space.
KNOWLEDGE WORK SYSTEMS (KWS)
Knowledge Work Systems serve the information needs of the knowledge level of the
organization. A knowledge worker is one who creates new knowledge or information by
research, experimentation and investigating into existing and new products and/or services.
They also ensure that new knowledge and technical expertise are integrated properly into an
organization. Examples of knowledge workers are engineers, architects, scientists and software
engineers to mention but a few. Knowledge work systems support knowledge workers in many
forms to enable them to carry out their above-mentioned functions. KWS require computers
with high-end specifications to run optimally. KWS includes applications such as computer
simulations, computer Aided Design/Manufacture (CAD/CAM) and investment workstation.
Features of KWS
a.
b.
c.
d.
KWS serves the information needs at the knowledge level of an organization.
KWS promotes the creation and integration of new knowledge into an organization.
It has a user-friendly interface to facilitate usage.
KWS require computers with high processing capabilities with regard to speed,
memory size, hard disk, etc.
MANAGEMENT INFORMATION SYSTEM (MIS)
Management Information System is an integrated, computer-based, user-machine system that
provides information for supporting operations and decision-making functions. (ACCA
Business Information Management, 2001).
MIS converts TPS data into summarized information (report) for monitoring performance and
managing an organization. Transactions recorded in a TPS are analyzed and produce routine
summary and exception report to middle level management to assist structured decisionmaking. MIS also aids management level decision makers with online and real-time access to
organization’s information.
MIS are sometimes used to mean all information systems that support the functional areas of
the organization. They have large quantities of input data and they produce summary reports
as output. MIS are used by middle managers. An example is an annual budgeting system.
Features of Management Information System
a. Summarises and reports on the basic operations of organisations.
b. It assists structured (routine) decision-making at all levels of management, particularly
middle level management.
c. Provides on-line and real-time access to TPS of the organizations as well as summary
of the performance of the business.
d. It focuses mainly on internal issues than concentrating on external matters concerning
environmental factors.
e. MIS have limited analytical capabilities.
Decision Support System (DSS)
DSS assists tactical management to go through the process of making decisions by providing
information, decision models, or analysis tools. DSS has support for semi structured and
unstructured decision-making. DSS facilitates analytical work, rather than routine processing
of transaction. DSS does mathematical and ‘what if analysis’, and creates models and different
options from which the manager uses his judgment to select the optimal one.
Features of DSS
a. It provides broad-based approach to supporting unstructured decision-making.
b. DSS relies on both internal information and external sources such as stock prices.
c. DSS uses mathematical, statistical, analytical models and “what if analysis”.
d. DSS has query capabilities and uses comprehensive database.
e. It is GUI-based and ease of use.
f. Outputs are less verbose, summarized and graphical.
Executive Information System (EIS)
EIS is also known as Executive Support System (ESS), and as the name suggests, it is designed
and used by top-level management. The need for ESS arose due to the inadequacies of MIS to
satisfy the need of executive managers. Most MIS produce output that did not give answers for
executive managers. ESS provides executives information that enables them to monitor what
is going on and also examine the business conditions in a readily accessible, interactive format.
It is analytical and has query capabilities. An EIS/ESS usually can provide summary over the
entire organization and also allows drilling down to specific levels of detail.
ESS is normally designed to cater for the needs of individual managers. They are interactive in
nature, programmed to minimize procedures for obtaining management information, and have
tools to produce graphical reports. ESS has access to online and real time external databases of
interest to the organization such as stock exchange, news, etc.
Features of ESS
a.
b.
c.
d.
e.
f.
g.
It is a type of DSS used by executive managers.
Monitor critical information and summarise them for management.
It addresses non-routine decisions requiring judgment.
It is highly interactive and easy to use.
Users go through minimal procedures to obtain results.
Online access to real time external databases.
Less verbose, output in the form of digital dashboard which displays graphical output,
charts etc.
h. It has analytical and predictive capabilities.
FUNDAMENTAL ROLES OF INFORMATION SYSTEMS IN BUSINESS
In general, information systems are established to perform the following roles to help
organizations to achieve their objectives:
a. Assist organizations in their business processes and operations.
b. Aid organizations in decision-making by their employees and managers.
c. Support organizations in their strategies for competitive advantage.
Assist Organizations in their Business Processes and Operations
Organizational functions are achieved through business processes and operations. Information
systems are equipped with the abilities that support or execute these processes and operations.
This capability ranges from providing electronic administrative support for business processes
to automating production lines and the provision of expert systems.
Aid Organizations in Decision-making by their Employees and Managers
An indispensable function of any manager is decision-making. An effective decision is one
that is based on accurate and timely information. The amount of data that management is
confronted with to aid them in their decision-making is so huge that they need information
systems to process them into the desired form.
Support Organizations in their Strategies for Competitive Advantage
Managements are confronted with fierce rivalry with their business competitors. An essential
tool that management can exploit to their advantage in their strategic decision-making
functions is information systems. It can enable management to produce quality goods and
services at reduced cost, among others.
UNIT 3: INTRODUCTION TO DATABASE SYSTEMS
Introduction
In the 1980s, the method of processing business records to produce information was mainly
the file oriented approach or file processing system. In this system, data is organized in the
form of different files. Compared to the manual system of record keeping and processing, this
method was reliable and faster. However as office operations grew, this file processing system
was characterized by some challenges and this necessitated the database management approach
which came in handy to solve the problems.
Database is now such an integral part of our day-to-day life that often we are not aware we are
using one. A database is a collection of related data and the Database Management System
(DBMS) to be the software that manages and controls access to the database. A database
application is simply a program that interacts with the database at some point in its execution.
We also use the more inclusive term database system to be a collection of application programs
that interact with the database along with the database base management system (DBMS) and
database itself.
THE HIERARCHY OF DATA
Data hierarchy refers to the systematic organization of data. Data stored within a DMBS form
a hierarchy, which are as follows:
Bit: The smallest unit of computer storage, or the smallest unit of data in a computer. A bit has
value of either 0 or 1.
Character: It is synonymous to a byte and it is the most basic logical data element. It consists
of a single alphabetic, numeric, or other symbol.
Field: A field is a group of characters that represents a named unit of information. A field
represents an attribute of an entity. For example, the field name ‘firstname’ contains the first
name of customers in a database.
Record: A collection of related fields that describe an entity within a file is called a record. For
example, a student record will have collection of fields such as registration number, name,
gender, programme and level.
File: A file is a collection of related records. A student file, for example, may contain all the
records of the individual students.
1
Database: It is an integrated collection of logically related records that are easily accessed,
managed or updated. The data stored are independent of the type application using them, as
well as the type of storage device on which they are stored.
Bit
Byte/Character
1
Field
Record
File
Database
Figure 3.1: Hierarchy of data
Definition of Terms
Entity: An entity is people, places, things or objects of importance about which data must be
captured, stored and maintained in a database. For example, a student records system may
contain an entity called ‘course’ whose fields are the attributes of interest to the system.
Attribute: An attribute is a characteristic or property of an entity. In relational database
terminology, an attribute usually means a column or field in a table. A typical attribute in a
customer table can be ‘first_name’ representing the first name of customers.
Primary Key: A Primary key is a field which uniquely identifies each record in a database. For
example, registration_number can be typical key in a student database.
2
Relation: There will be many cases when the data in one table can be related to the data in
another table. This connection between two tables is called a relation.
Foreign Key: When there is a relation between 2 tables, these tables will be connected by
inserting the primary key of one table into the corresponding row of the other table. The field
used in such a way to connect the 2 tables is called the foreign key.
Data: Data are a set of values of qualitative or quantitative variables about one or more persons
or objects. In simple words it is a collection of facts, such as numbers, words, measurements,
observations or just descriptions of things.
Database: A database is a named collection of tables. A database can also contain views,
indexes, sequences, data types, operators, and functions. Other relational database products use
the term catalog.
Query: A query is a type of command that retrieves data from the server.
Table: A table is a collection of rows. A table usually has a name, although some tables are
temporary and exist only to carry out a command. All the rows in a table have the same shape
(in other words, every row in a table contains the same set of columns).
Column (field, attribute): A column is the smallest unit of storage in a relational database. A
column represents one piece of information about an object. Every column has a name and a
data type. Columns are grouped into rows, and rows are grouped into tables.
Row (Tuple). In relational databases, a row is a data record within a table. Each row, which
represents a complete record of specific item data, holds different data within the same
structure. A row is occasionally referred to as a tuple.
3
Figure 3.2: Database Tables
Evolution of file-based systems
In daily life, we come across various needs to store data. It can be maintaining daily household
bills, bank account details, salary details, payment details, student information, student reports,
books in the library, etc. How will it be recorded in one place so that we can get it back when
required? It should be recorded in such a way that:
i.
Should be able to get the data any point in time latter
ii.
Should be able to add details to it whenever required
iii.
Should be able to modify stored information, as needed
iv.
Should also be able to delete them
In the traditional approach, that is, the pre-computer era, all pieces of information were stored
in papers. When we need information, we used to search through the papers. If we know a
particular date or category of information we are searching for, we go to that particular session
in the papers. When we want to update or delete some data, we search for it and modify them
or strike off them. If the data is limited, then all these tasks are easy. Imagine library
information or information about a student in school, or a banking system! How do we search
for single required data in papers? It is a never-ending task! Yes, Computers solved our
problems.
4
Traditional File-based System
The traditional file system is one earliest file management system. With this, data are
organized, stored and processed in independent file. Each application is designed to use its own
files and sharing of files is not facilitated. This means separate files are created and stored for
each application program. File-based systems were an early attempt to computerize the manual
filing system that we are all familiar with.
For example, in an organization a manual file is set up to hold all external and internal
correspondence relating to a project, product, task, client, or employee. Typically, there are
many such files, and for safety they are labeled and stored in one or more cabinets. For security,
the cabinets may have locks or may be located in secure areas of the building. In our own home,
we probably have some sort of filing system which contains receipts, guarantees, invoices,
bank statements, and such like. When we need to look something up, we go to the filing system
and search through the system starting from the first entry until we find what we want.
Alternatively, we may have an indexing system that helps locate what we want more quickly.
The manual filing system works well while the number of items to be stored is small. It even
works quite adequately when there are large numbers of items and we have only to store and
retrieve them. However, the manual filing system breaks down when we have to crossreference or process the information in the files.
This file system results in duplication of data, it is inflexible, inefficient, and has limited
capabilities.
Academic
Library
Hospital
Academic
Records
Programs
Library
Management
Programs
Hospital
Information
System
Report
Report
Report
Figure 3.3: Traditional File System
5
Limitations of the File-Based Approach
i.
Separation and isolation of data: Data is tied to a specific program. When data is
isolated in separate files, it is more difficult to access data that should be available. For
example, if we want to produce a list of all houses that match the requirements of
clients, we first need to create a temporary file of those clients who have ‘house’ as the
preferred type. We then search the file for those properties where the property type is
‘house’ and the rent is less than the client’s maximum rent. With file systems, such
processing is difficult. The application developer must synchronize the processing of
two files to ensure the correct data is extracted. This difficulty is compounded if we
require data from more than two files.
ii.
Duplication of data: Owing to the decentralized approach taken by each department,
the file-based approach encouraged, if not necessitated, the uncontrolled duplication of
data
iii.
Incompatible file formats: Because the structure of files is embedded in the application
programs, the structures are dependent on the application programming language. For
example, the structure of a file generated by a one program may be different from the
structure of a file generated by a another program. The direct incompatibility of such
files makes them difficult to process jointly.
iv.
Data Redundancy or Duplication: Data redundancy simply means that some data fields
appear more than once in the system. This is as a result of files being independent of
each other. When files are stored more than once, the end result is waste of storage
space and duplicates effort in maintaining the data. Redundancy results in inconsistent
database. Database designers attempt to eliminate this problem by the use of a technique
called normalization.
v.
Inconsistent Data: Once data redundancy exists, updating of files or files become
burdensome as attempts have to be made to update all redundant fields or fields in
various locations whenever one is updated. However, this is difficult to achieve and the
end results is that not all the fields and files in the various locations are updated, thus
leading to inconsistent and unambiguous data.
vi.
Porous Data Security: It is challenging to ensure secured system when the files or
databases are not integrated and they exist in isolation.
6
vii.
Poor Data Integrity: Data integrity is ensuring quality data in a system. The traditional
file approach has poor data integrity, as it is difficult to ensure that data entered is valid,
accurate and consistent. However, it is easy to enforce integrity rules with the database
approach.
Database Approach
All the above limitations of the file-based approach can be attributed to two factors:
i.
The data is embedded in the application programs, rather than being stored separately
and independently;
ii.
There is no control over the access and manipulation of data beyond that imposed by
the application programs.
Database
Database is a shared collection of logically related data, and a description of this data, designed
to meet the information needs of an organization. Database is a single, possibly large repository
of data that can be used simultaneously by many departments and users. Instead of
disconnected files with redundant data, all data items are integrated with a minimum amount
of duplication. The database is no longer owned by one department but is a shared corporate
resource. The database holds not only the organization’s operational data but also a description
of this data. For this reason, a database is also defined as a self-describing collection of
integrated records. The description of the data is known as the system catalog (or data
dictionary or metadata– the ‘data about data’). It is the self-describing nature of a database that
provides program–data independence.
The approach taken with database systems, where the definition of data is separated from the
application programs, is similar to the approach taken in modern software development, where
an internal definition of an object and a separate external definition are provided. The users of
an object see only the external definition and are unaware of how the object is defined and how
it functions. One advantage of this approach, known as data abstraction, is that we can change
the internal definition of an object without affecting the users of the object, provided the
external definition remains the same. In the same way, the database approach separates the
structure of the data from the application programs and stores it in the database. If new data
7
structures are added or existing structures are modified then the application programs are
unaffected, provided they do not directly depend upon what has been modified. For example,
if we add a new field to a record or create a new file, existing applications are unaffected.
However, if we remove a field from a file that an application program uses, then that application
program is affected by this change and must be modified accordingly.
The final term in the definition of a database that we should explain is ‘logically related’.
When we analyze the information needs of an organization, we attempt to identify entities,
attributes, and relationships. An entity is a distinct object (a person, place, thing, concept, or
event) in the organization that is to be represented in the database. An attribute is a property
that describes some aspect of the object that we wish to record, and a relationship is an
association between entities.
8
Users/Programmers
Application Programs/Queries
Database
Management
Software
Software to Process
Queries/Programs
Software to Access
Stored Data
Stored Database
Definition
Figure 1.3: Database Approach.
Stored Database
(Meta Data)
Figure 3.4: Database Management System
The Database Management System (DBMS)
DBMS is a software system that enables users to define, create, maintain, and control access
to the database. Some DBMS examples include MySQL, PostgreSQL, Microsoft Access,
SQL Server, FileMaker, Oracle, RDBMS, dBASE, Clipper, and FoxPro.
DBMS has the following manipulative functions among others:
a. To retrieve data.
b. To add, update and delete records.
c. To control access to the records.
d. To recover data in case of system crash or system breakdown.
The DBMS is the software that interacts with the users’ application programs and the database.
9
Elements of Database Management Systems
A Database management system has three elements:
a. Data definition language
b. Data manipulation language
c. Data Dictionary
Data Definition Language (DDL)
These are statements used to define the database structure. It allows a database designer to
define the database using a Data Definition Language (DDL) provided for the particular
DBMS. The DDL allows the designer to specify the data types and structures, and the
constraints on the data to be stored in the database.
Data Manipulation Language (DML)
A data manipulation language is a specialized language used to manage (accessing and
manipulating) a database; that is, select, insert, delete, update, retrieve data etc. As an element
of fourth generation language, DMLs are easily used by non-technical people with little
knowledge in databases.
Data Dictionary
It contains data about of data (metadata). Data dictionary contains the actual database
descriptions managed by the DBMS. Key information such as the file name, description,
number of records in the file, who uses the data, who owns it and access rights are stored in the
data dictionary.
Database Application Programs
A typical database application program is a computer program that interacts with the database
by issuing an appropriate request (typically an SQL statement) to the DBMS.
10
Users interact with the database through a number of application programs that are used to
create and maintain the database and to generate information. These programs can be
conventional batch applications or, more typically nowadays, they will be online applications.
The application programs may be written in some programming language or in some higherlevel fourth-generation language.
Structured Query Language (SQL)
SQL is used to communicate with a database. SQL is a standard language for relational
database management systems. SQL statements are used to perform tasks such as update data
on a database, or retrieve data from a database. Some common relational database management
systems that use SQL are: Oracle, Sybase, Microsoft SQL Server, Access, etc. Although most
database systems use SQL, most of them also have their own additional proprietary extensions
that are usually only used on their system. However, the standard SQL commands such as
"Select", "Insert", "Update", "Delete", "Create", and "Drop" can be used to accomplish almost
everything that one needs to do with a database
Components of the DBMS Environment
The five major components in the DBMS environment: hardware, software, data, procedures,
and people.
Hardware
The DBMS and the applications require hardware to run. The hardware can range from a single
personal computer, to a single mainframe, to a network of computers. The particular hardware
depends on the organization’s requirements and the DBMS used. Some DBMSs run only on
particular hardware or operating systems, while others run on a wide variety of hardware and
operating systems. A DBMS requires a minimum amount of main memory and disk space to
run, but this minimum configuration may not necessarily give acceptable performance. A
backend of the DBMS is, the part of the DBMS that manages and controls access to the
database. A frontend of the DBMS is, the part of the DBMS that interfaces with the user. This
is called a client–server architecture: the backend is the server and the frontends are the clients.
11
Software
The software component comprises the DBMS software itself and the application programs,
together with the operating system, including network software if the DBMS is being used over
a network. Typically, application programs are written in a third-generation programming
language (3GL), such as ‘C’, C++, Java, Visual Basic, COBOL, Fortran, Ada, or
Pascal, or using a fourth-generation language (4GL), such as SQL, embedded in a third
generation language. The target DBMS may have its own fourth-generation tools that allow
rapid development of applications through the provision of non-procedural query languages,
reports generators, forms generators, graphics generators, and application generators. The use
of fourth-generation tools can improve productivity significantly and produce programs that
are easier to maintain.
Data
Perhaps the most important component of the DBMS environment, certainly from the endusers’ point of view, is the data. The database contains both the operational data and the
metadata, the ‘data about data’. The structure of the database is called the schema.
Procedures
Procedures refer to the instructions and rules that govern the design and use of the database.
The users of the system and the staff that manage the database require documented procedures
on how to use or run the system. These may consist of instructions on how to:
i.
Log on to the DBMS;
ii.
Use a particular DBMS facility or application program;
iii.
Start and stop the DBMS;
iv.
Make backup copies of the database;
v.
Handle hardware or software failures. This may include procedures on how to identify
the failed component, how to fix the failed component (for example, telephone the
appropriate hardware engineer) and, following the repair of the fault, how to recover
the database;
vi.
Change the structure of a table, reorganize the database across multiple disks, improve
performance, or archive data to secondary storage.
People
The final component is the people involved with the system.
12
Roles in the Database Environment
The following are the roles (positions or responsibilities) are usually found in in a database
environment:
1. Data and Database Administrators
The database and the DBMS are corporate resources that must be managed like any other
resource. Data and database administration are the roles generally associated with the
management and control of a DBMS and its data. The Data Administrator (DA) is responsible
for the management of the data resource including database planning, development and
maintenance of standards, policies and procedures, and conceptual/logical database design.
The DA consults with and advises senior managers, ensuring that the direction of database
development will ultimately support corporate objectives.
The Database Administrator (DBA) is responsible for the physical realization of the database,
including physical database design and implementation, security and integrity control,
maintenance of the operational system, and ensuring satisfactory performance of the
applications for users. The role of the DBA is more technically oriented than the role of the
DA, requiring detailed knowledge of the target DBMS and the system environment. In some
organizations there is no distinction between these two roles; in others, the importance of the
corporate resources is reflected in the allocation of teams of staff dedicated to each of these
roles.
Administering the DBMS
An organization’s DBMS needs to be managed if its full benefits are to be achieved.
Organizations therefore have the position of a Database Administrator (DBA) whose duty is
the routine administration of the database. This job is very important since most organizations
keep their information in databases.
Functions of the Database Administrator
The following are the generic function of DBA:
a. Selection of hardware and software.
13
b. Decides the content and structure of the database.
c. Determines the storage structure and where data should be stored.
d. Managing data security, access and privacy controls.
e. Managing data Integrity.
f. Taking of database backup.
g. Deciding on database recovery procedures.
h. Fine-tuning database performance.
i. Improving query processing performance
2. Database Designers
In large database design projects, we can distinguish between two types of designer: logical
database designers and physical database designers. The logical database designer is concerned
with identifying the data (that is, the entities and attributes), the relationships between the data,
and the constraints on the data that is to be stored in the database.
The logical database designer must have a thorough and complete understanding of the
organization’s data and any constraints on this data (the constraints are sometimes called
business rules).
To be effective, the logical database designer must involve all prospective database users in the
development of the data model, and this involvement should begin as early in the process as
possible. In this book, we split the work of the logical database designer into two stages:
Conceptual database design, which is independent of implementation details such as the
target DBMS, application programs, programming languages, or any other physical
considerations;
Logical database design, which targets a specific data model, such as relational, network,
hierarchical, or object-oriented.
3. Application Developers
Once the database has been implemented, the application programs that provide the required
functionality for the end-users must be implemented. This is the responsibility of the
application developers. Typically, the application developers work from a specification
produced by systems analysts. Each program contains statements that request the
14
DBMS to perform some operation on the database. This includes retrieving data, inserting,
updating, and deleting data. The programs may be written in a third-generation programming
language or a fourth-generation language, as discussed in the previous section.
End-Users
The end-users are the ‘clients’ for the database, which has been designed and implemented,
and is being maintained to serve their information needs. End-users can be classified according
to the way they use the system:
1. Naïve users: are typically unaware of the DBMS. They access the database through
specially written application programs that attempt to make the operations as simple as
possible. They invoke database operations by entering simple commands or choosing
options from a menu. This means that they do not need to know anything about the
database or the DBMS. For example, the checkout assistant at the local supermarket
uses a bar code reader to find out the price of the item. However, there is an application
program present that reads the bar code, looks up the price of the item in the database,
reduces the database field containing the number of such items in stock, and displays
the price on the till.
2. Sophisticated users: At the other end of the spectrum, the sophisticated end-user is
familiar with the structure of the database and the facilities offered by the DBMS.
Sophisticated end-users may use a high-level query language such as SQL to perform
the required operations. Some sophisticated end-users may even write application
programs for their own use.
Characteristics of Database
The database approach has some very characteristic features which are discussed in detail
below:
15
Concurrent Use
A database system allows several users to access the database concurrently. Answering
different questions from different users with the same (base) data is a central aspect of an
information system. Such concurrent use of data increases the economy of a system.
An example for concurrent use is the travel database of a bigger travel agency. The employees
of different branches can access the database concurrently and book journeys for their clients.
Each travel agent sees on his interface if there are still seats available for a specific journey or
if it is already fully booked.
Structured and Described Data
A fundamental feature of the database approach is that the database systems does not only
contain the data but also the complete definition and description of these data. These
descriptions are basically details about the extent, the structure, the type and the format of all
data and, additionally, the relationship between the data. This kind of stored data is called
metadata ("data about data").
Separation of Data and Applications
As described in the feature structured data the structure of a database is described through
metadata which is also stored in the database. An application software does not need any
knowledge about the physical data storage like encoding, format, storage place, etc. It only
communicates with the management system f a database (DBMS) via a standardised interface
with the help of a standardised language like SQL. The access to the data and the metadata is
entirely done by the DBMS. In this way all the applications can be totally seperated from the
data. Therefore database internal reorganisations or improvement of efficiency do not have any
influence on the application software.
Data Integrity
Data integrity is a byword for the quality and the reliability of the data of a database system.
In a broader sense data integrity includes also the protection of the database from unauthorised
access (confidentiality) and unauthorised changes. Data reflect facts of the real world. database.
Transactions
A transaction is a bundle of actions which are done within a database to bring it from one
16
consistent state to a new consistent state. In between the data are inevitable inconsistent. A
transaction is atomic what means that it cannot be divided up any further. Within a transaction
all or none of the actions need to be carried out. Doing only a part of the actions would lead to
an inconsistent database state. One example of a transaction is the transfer of an amount of
money from one bank account to another. The debit of the money from one account and the
credit of it to another account makes together a consistent transaction. This transaction is also
atomic. The debit or credit alone would both lead to an inconsistent state. After finishing the
transaction (debit and credit) the changes to both accounts become persistent and the one who
gave the money has now less money on his account while the receiver has now a higher
balance.
Data Persistence
Data persistence means that in a DBMS all data is maintained as long as it is not deleted
explicitly. The life span of data needs to be determined directly or indirectly be the user and
must not be dependent on system features. Additionally data once stored in a database must
not be lost. Changes of a database which are done by a transaction are persistent. When a
transaction is finished even a system crash cannot put the data in danger.
Advantages of DBMS
The following are some of the advantages of the DBMS;
1. Control of data redundancy
As discussed earlier, traditional file-based systems waste space by storing the same information
in more than one file. In contrast, the database approach attempts to eliminate the redundancy
by integrating the files so that multiple copies of the same data are not stored. However, the
database approach does not eliminate redundancy entirely, but controls the amount of
redundancy inherent in the database. Sometimes, it is necessary to duplicate key data items to
model relationships.
2. Data consistency
By eliminating or controlling redundancy, we reduce the risk of inconsistencies occurring.
If a data item is stored only once in the database, any update to its value has to be performed
only once and the new value is available immediately to all users. If a data item is stored more
17
than once and the system is aware of this, the system can ensure that all copies of the item are
kept consistent. Unfortunately, many of today’s DBMSs do not automatically ensure this type
of consistency. More information from the same amount of data with the integration of the
operational data, it may be possible for the organization to derive additional information from
the same data.
3. Sharing of data
Typically, files are owned by the people or departments that use them. On the other hand, the
database belongs to the entire organization and can be shared by all authorized users. In this
way, more users share more of the data. Furthermore, new applications can build on the existing
data in the database and add only data that is not currently stored, rather than having to define
all data requirements again. The new applications can also rely on the functions provided by
the DBMS, such as data definition and manipulation, and concurrency and recovery control,
rather than having to provide these functions themselves.
4. Improved data integrity
Database integrity refers to the validity and consistency of stored data. Integrity is usually
expressed in terms of constraints, which are consistency rules that the database is not permitted
to violate. Constraints may apply to data items within a single record or they may apply to
relationships between records. For example, an integrity constraint could state that a member
of staff’s salary cannot be greater than ghc40,000 or that the branch number contained in a staff
record, representing the branch where the member of staff works, must correspond to an
existing branch office. Again, integration allows the DBA to define, and the DBMS to enforce,
integrity constraints.
5. Improved security
Database security is the protection of the database from unauthorized users. Without suitable
security measures, integration makes the data more vulnerable than file-based systems.
However, integration allows the DBA to define, and the DBMS to enforce, database security.
This may take the form of user names and passwords to identify people authorized to use the
database. The access that an authorized user is allowed on the data may be restricted by the
operation type (retrieval, insert, update, delete). For example, the DBA has access to all the
data in the database; a branch manager may have access to all data that relates to his or her
18
branch office; and a sales assistant may have access to all data relating to properties but no
access to sensitive data such as staff salary details.
6. Enforcement of standards
Again, integration allows the DBA to define and enforce the necessary standards. These may
include departmental, organizational, national, or international standards for such things as data
formats to facilitate exchange of data between systems, naming conventions, documentation
standards, update procedures, and access rules.
7. Economy of scale
Combining all the organization’s operational data into one database, and creating a set of
applications that work on this one source of data, can result in cost savings. In this case, the
budget that would normally be allocated to each department for the development and
maintenance of its file-based system can be combined, possibly resulting in a lower total cost,
leading to an economy of scale. The combined budget can be used to buy a system
configuration that is more suited to the organization’s needs. This may consist of one large,
powerful computer or a network of smaller computers.
8. Balance of conflicting requirements
Each user or department has needs that may be in conflict with the needs of other users. Since
the database is under the control of the DBA, the DBA can make decisions about the design
and operational use of the database that provide the best use of resources for the organization
as a whole. These decisions will provide optimal performance for important applications,
possibly at the expense of less critical ones.
9. Improved data accessibility and responsiveness
Again, as a result of integration, data that crosses departmental boundaries is directly accessible
to the end-users. This provides a system with potentially much more functionality that can, for
example, be used to provide better services to the end-user or the organization’s clients. Many
DBMSs provide query languages or report writers that allow users to ask ad hoc questions and
to obtain the required information almost immediately at their terminal, without requiring a
programmer to write some software to extract this information from the database. For example,
a branch manager could list all flats with a monthly rent greater than ghc 400 by entering the
following SQL command at a terminal:
19
SELECT*
FROM PropertyForRent
WHERE type =‘Flat’ AND rent >400;
10. Increased productivity
As mentioned previously, the DBMS provides many of the standard functions that the
programmer would normally have to write in a file-based application. At a basic level, the
DBMS provides all the low-level file-handling routines that are typical in application
programs. The provision of these functions allows the programmer to concentrate on the
specific functionality required by the users without having to worry about low-level
implementation details. Many DBMSs also provide a fourth-generation environment
consisting of tools to simplify the development of database applications. This results in
increased programmer productivity and reduced development time (with associated cost
savings).
11. Improved maintenance through data independence
In file-based systems, the descriptions of the data and the logic for accessing the data are built
into each application program, making the programs dependent on the data. A change to the
structure of the data, for example making an address 41 characters instead of 40 characters, or
a change to the way the data is stored on disk, can require substantial alterations to the programs
that are affected by the change. In contrast, a DBMS separates the data descriptions from the
applications, thereby making applications immune to changes in the data descriptions. This is
known as data independence. The provision of data independence simplifies database
application maintenance.
12. Increased concurrency
In some file-based systems, if two or more users are allowed to access the same file
simultaneously, it is possible that the accesses will interfere with each other, resulting in loss
of information or even loss of integrity. Many DBMSs manage concurrent database access and
ensure such problems cannot occur.
13. Improved backup and recovery services
Many file-based systems place the responsibility on the user to provide measures to protect the
data from failures to the computer system or application program. This may involve taking a
20
nightly backup of the data. In the event of a failure during the next day, the backup is restored
and the work that has taken place since this backup is lost and has to be re-entered. In contrast,
modern DBMSs provide facilities to minimize the amount of processing that is lost following
a failure.
Disadvantages of DBMS
Despite the advantages, DBMS has the following disadvantages;
1. Complexity
The provision of the functionality we expect of a good DBMS makes the DBMS an extremely
complex piece of software. Database designers and developers, the data and database
administrators, and end-users must understand this functionality to take full advantage of it.
Failure to understand the system can lead to bad design decisions, which can have serious
consequences for an organization.
2. Size
The complexity and breadth of functionality makes the DBMS an extremely large piece of
software, occupying many megabytes of disk space and requiring substantial amounts of
memory to run efficiently.
3. Cost of DBMSs
The cost of DBMSs varies significantly, depending on the environment and functionality
provided. For example, a single-user DBMS for a personal computer may only cost US$100.
However, a large mainframe multi-user DBMS servicing hundreds of users can be extremely
expensive. There is also the recurrent annual maintenance cost, which is typically a percentage
of the list price.
4. Additional hardware costs
The disk storage requirements for the DBMS and the database may necessitate the purchase of
additional storage space. Furthermore, to achieve the required performance, it may be
necessary to purchase a larger machine, perhaps even a machine dedicated to running the
DBMS. The procurement of additional hardware results in further expenditure.
5. Cost of conversion
21
In some situations, the cost of the DBMS and extra hardware may be insignificant compared
with the cost of converting existing applications to run on the new DBMS and hardware. This
cost also includes the cost of training staff to use these new systems, and possibly the
employment of specialist staff to help with the conversion and running of the system. This cost
is one of the main reasons why some organizations feel tied to their current systems and cannot
switch to more modern database technology. The term legacy system is sometimes used to refer
to an older, and usually inferior, system.
6. Performance
Typically, a file-based system is written for a specific application, such as invoicing. As a result,
performance is generally very good. However, the DBMS is written to be more general, to cater
for many applications rather than just one. The effect is that some applications may not run as
fast as they used to.
7. Higher impact of a failure
The centralization of resources increases the vulnerability of the system. Since all users and
applications rely on the availability of the DBMS, the failure of certain components can bring
operations to a halt.
Importance of Database in an Organisation
1. Simplify the search for and use of information within an organisation.
2. A good database allows an organisation to closely monitor the progress of the operation,
allowing them to take quick and appropriate action if a problem arises.
3. Assisting in the organisation of data owned by the organisation, such as employee bios,
students records, consumer biodata, product list, salary payment, bill payment, and
others.
4. Facilitate the members' data access activities, which include data acquisition and
manipulation, such as adding and deleting data, using the authority that has been
granted.
5. Maintaining the data security of the organization, because any data can be protected by
providing a login and password for each data.
6. The database can aid in the development of a better strategy for the future advancement
of an organization.
7. Assist marketing activities for the database in collecting complete and detailed
customer data in order to facilitate marketing activities for an organization or company.
8. A database can help an organization or company save money on operating costs when
it comes to managing information. The organization can be well organized with a
22
database of all the information so that it can be accessed quickly and easily without
spending a lot of money.
Database Structures
This section describes four (4) database structures which are relational databases, hierarchical
databases, network databases and object-oriented databases. Regardless of the database
structure used, there are two ways of looking at how data is stored and retrieved. These are the
logical view and physical view of data.
Logical View and Physical View of Data
The logical view is more conceptual and abstract than the physical view. The logical level
describes the data stored (name of the tables, their attributes, types and constraints) and the
logical relationship among the data. Logical view thus describes the organization’s
requirements for the data.
The physical view on the other hand describes how records are stored, that is, the most effective
way of storing, retrieving the objects, backup and recovery issues, among others.
Four Types of DBMS
There are various types of Database Management Systems. Four of them are discussed below.
Relational DMBS
In relational DBMS, the relationship between data files is relational, not hierarchical and the
databases are in the form of tables (table-oriented) with rows and columns. Data in the various
tables are related by common key. Relational databases work on the principle that each table
has a key field that uniquely identifies each row, and that these key fields can be used to connect
one table of data to another. Relational databases are more flexible than either the hierarchical
or network database structures and comparatively simple and easy to implement.
23
In figure 1.4, record keys within the tables are used to link the tables. Student_file uses Studid
to link with Studid in Assessment_file, and uses Progid and Hallid to link the Programme_File
and Hall_File respectively. Programme_File and Hall_File are linked by Facultyid in the
respective tables.
24
Student_ File
Studid
First Name
Middle Name
Last Name
Progid
Hallid
Assessment_File
Programme_File
Progid
Facultyid
Programme Name
Hall_File
Hallid
Studid
Hall Name
Quiz1
Facultyid
Quiz2
Faculty Name
Exam
Total
Grade
Figure 3.5: Relational DMBS
Hierarchical DMBS
In Hierarchical DMBS, database is organized in pyramid fashion, like the branches of a tree
extending downwards; refer to figure 1.5. The records are linked together such that each child
record is linked to a parent record, but a parent can have more than one child record linked to
it. A child can also be a parent with children beneath it. It is commonly used by mainframe
computers and is one of the oldest approaches of organizing and storing data.
The advantage of hierarchical databases is that they can be accessed and updated rapidly
because the tree-like structure and the relationships between records are defined in advance.
The disadvantage of this type of database structure is that each child in the tree may have only
one parent and relationships or linkages between children are not permitted, even if they make
sense from a logical standpoint. Hierarchical databases are so rigid in their design that adding
a new field or record requires that the entire database be redefined.
25
UNIVERSITY
FACULTY A
DEPT A2
DEPT A1
FACULTY B
DEPT B1
DEPT B2
FACULTY C
DEPT B3
DEPT C1
DEPT C2
Figure 3.6: Hierarchical database management system
Network DMBS
As the name suggests, network databases are interconnected (cobweb) network of records.
With network databases, each child or member can have more than one parent or owner as
depicted in figure 1.6. Like hierarchical databases, network databases are used on mainframe
computers.
Since more connections can be made between different types of data, network databases are
considered more flexible. The limitations are that similar to hierarchical databases, network
databases must be defined in advance. There is also a limit to the number of connections that
can be made between records.
Football
Football
School A
Hockey
School B
School C
Table Tennis
School D
School E
Figure 3.7: Network database management system
Object-oriented DBMS
Object-oriented DBMS offers more advanced capabilities than the other databases.
Hierarchical and network databases handle data that can be represented by rows and columns.
Object-oriented database can be used to store data in a variety of forms such as text, audio and
video.
26
The disadvantages associated with object-oriented databases are that, they are more expensive
to develop. Also, most organizations find themselves attached (’lock-in’) to a system that they
have already deployed and are therefore reluctant to abandon or convert from those databases.
However, the benefits to object-oriented databases are convincing. The ability to mix and
match reusable objects provides greater multimedia capability.
Object 1: Pay Slip Report
Object 1 Instance
Staff number
2022189
Name
Christiana Oppey
Number of hours
45
Pay Rate
90
Gross pay
4050
Tax
405
Net pay
3654
Object 2: Social Security Report
Staff number
Name
Social Security Contribution
Figure 3.8: Object-oriented DBMS
DATABASE ADMINISTRATION
Database administration is the management of the physical realization of a database system,
which includes physical database design and implementation, setting security and integrity
27
controls, monitoring system performance, and reorganizing the database, as necessary. Thus
Database administration refers to the whole set of activities performed by a database
administrator to ensure that a database is always available as needed
The database administration staff are more technically oriented than the data administration
staff, requiring knowledge of specific DBMSs and the operating system environment.
Although the primary responsibilities are centered on developing and maintaining systems
using the DBMS software to its fullest extent, DBA staff also assist DA staff in other areas.
Database Users
Database users are the one who really use and take the benefits of database. There will be
different types of users depending on their need and way of accessing the database.
a. Application Programmers – They are the developers who interact with the database
by means of DML queries. These DML queries are written in the application programs
like C, C++, JAVA, Pascal etc. These queries are converted into object code to
communicate with the database. For example, writing a C program to generate the
report of employees who are working in particular department will involve a query to
fetch the data from database. It will include embedded SQL query in the C Program.
b. Sophisticated Users – They are database developers, who write SQL queries to
select/insert/delete/update data. They do not use any application or programs to request
the database. They directly interact with the database by means of query language like
SQL. These users will be scientists, engineers, analysts who thoroughly study SQL and
DBMS to apply the concepts in their requirement. In short, we can say this category
includes designers and developers of DBMS and SQL.
c. Specialized Users – These are also sophisticated users, but they write special database
application programs. They are the developers who develop the complex programs to
the requirement.
d. Stand-alone Users – These users will have stand –alone database for their personal
use. These kinds of database will have readymade database packages which will have
menus and graphical interfaces.
e. Native Users – these are the users who use the existing application to interact with the
database. For example, online library system, ticket booking systems, ATMs etc which
28
has existing application and users use them to interact with the database to fulfill their
requests.
Types of DBA
There are different kinds of DBA depending on the responsibility that one owns.
a.
Administrative DBA – This DBA is mainly concerned with installing, and maintaining
DBMS servers. His prime tasks are installing, backups, recovery, security, replications,
memory management, configurations and tuning. He is mainly responsible for all
administrative tasks of a database.
b.
Development DBA – He is responsible for creating queries and procedure for the
requirement. Basically his task is similar to any database developer.
c.
Database Architect – Database architect is responsible for creating and maintaining
the users, roles, access rights, tables, views, constraints and indexes. He is mainly
responsible for designing the structure of the database depending on the requirement.
These structures will be used by developers and development DBA to code.
d.
Data Warehouse DBA –DBA should be able to maintain the data and procedures from
various sources in the data warehouse. These sources can be files, COBOL, or any other
programs. Here data and programs will be from different sources. A good DBA should
be able to keep the performance and function levels from these sources at same pace to
make the data warehouse to work.
e.
Application DBA –He acts like a bridge between the application program and the
database. He makes sure all the application program is optimized to interact with the
database. He ensures all the activities from installing, upgrading, and patching,
maintaining, backup, recovery to executing the records works without any issues.
f.
OLAP DBA – He is responsible for installing and maintaining the database in OLAP
systems. He maintains only OLAP databases.
Database administration tasks.
a. Evaluating and selecting DBMS products.
b. Undertaking physical database design.
c. Implementing a physical database design using a target DBMS.
d. Defining security and integrity constraints.
29
e. Liaising with database application developers.
f. Developing test strategies.
g. Training users.
h. Responsible for ‘signing off’ the implemented database system.
i. Monitoring system performance and tuning the database, as appropriate.
j. Performing backups routinely.
k. Ensuring recovery mechanisms and procedures are in place.
l. Ensuring documentation is complete including in-house produced material.\
m. Keeping up to date with software and hardware developments and costs, and installing
updates as necessary.
n. Selection of hardware and software
o. Tuning database performance
p. Improving query processing performance
Additional Reading Resources
Elmasri, R. & Navathe, S.B.(2011). Fundamentals of Database Systems (6 Ed.). Boston:
Addison-Wesley.
30
UNIT4: ELECTRONIC BUSINESS
Electronic business, also known as e-business or Internet business may be defined as the
application of information and communication technologies (ICT) in support of all the
activities of business. E-business is broader than e-commerce.
Benefits of e-business
The benefits of e-business are enormous. Some of them are discussed below.
Create cost savings and operational efficiencies: E-business leads to cost savings and
operational efficiencies as most of the manual aspects of doing business and their associated
inefficiencies are replaced by electronic means which eliminates the bottlenecks associated
with the traditional ways of business.
Reach out more customers and markets: With the Internet as the medium, one’s clients in
ebusiness are the whole world due to the ubiquitous nature of the Internet. Thus, making the
potential market size very big.
Make it easier to do business: With distance not barrier in e-business, doing business via the
net is devoid of the challenges associated with the traditional way of doing business.
Meet the needs and expectations of customers and clients: Ebusiness ensures better and
quicker customer service. E-business allows people to carry out transactions without the
barriers of time or distance. One can log on to the Internet at any point in time, be it day or
night and transact business. This encourages clients to transact business at their convenience.
Improve Marketing and Promotion: A well designed website is also an excellent medium
for advertizing what one does, with an added advantage of reaching everyone connected to the
net. E-business also facilitates targeted and personalized marketing.
Strategic and Operational Benefits: The strategic and operational benefits of making a
business ‘ebusiness enabled’ are that they help reduce the delivery time, labour cost and other
cost incurred in business.
Challenges of e-Business
Hardware and Software Cost: High cost associated with providing hardware, software etc.,
to ensure the confidentiality and privacy of the transaction. Especially the information
concerning customer credit card number, password and other bank details.
No Paper-based Copy to Track Operations: Absence of paper-based copy of transaction to
assist audit trail when the need arises.
Risk of Abuse by Service Provider: Some mischievous ecommerce providers and untrusted
traders can misuse confidential information relating to their clients for personal purposes.
Security Threats: Ebusiness like most online-based transactions are prone to the activities of
hackers, crackers and other Internet security threats. Customers also feel insecure about the
integrity and confidentiality relating to their details about their transaction, in particular those
concerning their credit cards etc.
IMPLICATIONS OF THE INTERNET ON BUSINESS
Increased Revenue as a result of Global-Wide Market Size
The Internet has provided opportunity to make goods and services available online to globalwide customers. This translates into more revenue.
EDI Becomes the Standard Method of Doing Business
Electronic Data Interchange (EDI) is the electronic transmission or interchange of
data/information using standardized format between organizations. EDI has become
indispensable in ecommerce.
Reduced Transaction Cost
With EDI transaction, cost associated with business is reduced significantly. This is because
most things are done electronically and they are devoid of the costs that are associated with the
traditional way of carrying out transactions.
Decreased use of Cash
Doing business via Internet is devoid of face-to-face contact. Thus, payments are done using
credit cards and other digital cash media. The risk of carrying cash is absent.
Elimination of Intermediary Organizations
With ecommerce, the buyer and the seller of goods or services interact directly without any
intermediary such as a retailer, which is a benefit to the customer since it eliminates cost.
Personalised or Individualised Marketing
Internet facilitates the situation of targeting a product or service to an individual customer. The
Internet is able to collect information about individual taste, interest and preferences and then
creates product and/or advertisement of special interest to that individual.
Increased use of Intranets or Extranets
As we know, both the Intranet and Extranet are all ‘offspring’ of the Internet. They are used
extensively in business for various purposes.
Telecommuting
The advent of Internet has given rise to telecommuting which is the situation where people
work from remote location, usually home, using computers, fax, telephone, etc., and
electronically linking to work/office to perform similar work rather than commuting to and
from office.
Increased Competition
Competition is rife among businesses as all customers are within the reach of every
organization via the Internet.
ELECTRONIC COMMERCE
Electronic commerce, commonly known as e-commerce or ecommerce, consists of the buying
and selling of products or services over the Internet and other computer networks. E-commerce
is a subset of e-business. Most big retailers have electronic commerce presence on the World
Wide Web. E-retail, e-wholesale, e-marketing are also derivatives of ecommerce, and are
commercial entities that operate their business only on the Internet.
In e-commerce, businesses use online advertisements, also known as online marketing or
Internet marketing to deliver marketing messages to potential customers.
Types of Electronic Commerce
Ecommerce can be classified according to the participants in the transactions. By that
classification, the following types can be identified:
B2B: Electronic commerce that is conducted between businesses is referred to as business-tobusiness (B-to-B, B2B). For example, an ecommerce transaction between a manufacturer and
a wholesaler.
B2G: Exchange of goods and services from one business to a government agency is referred
to as business-to-government (B-to-G, B2G).
B2C: Electronic commerce that is conducted between businesses and individual consumers is
referred to as business-to-consumer (B-to-C, B2C). This is the type of electronic commerce
conducted by companies such as Amazon.com.
C2C: Electronic commerce that is conducted between a consumer and another is referred to as
consumer-to-consumer (C-to-C, C2C). C2C is an Internet facilitated transaction between
consumers through a third party. The most common form of C2C is the online auction. In this
form of C2C, consumers post items for sale and other consumers bid to buy them. The third
party that facilitates the transaction may charge a fee or commission. eBay is one of most
foremost online market place where buyers and sellers meet and trade in wide amount of goods.
In Ghana for example, tonaton.com provides the facilities that connects sellers and buyers to
do their transaction electronically.
Advantages of ecommerce
The following are some of the advantages of ecommerce:
a. E-commerce allows products to be sold directly to consumers without the need of
retailers. At the convenience of your home or office, one can order an HP computer
from www.hp.com.
b.
A benefit of ecommerce to customers is that, it facilitates them to make price and
product comparison between businesses. It is very easy to make price and product
comparisons online. Sites such as BizRate, NexTag and shopLocal help to find the
best price of a product.
c. Faster buying and selling procedure.
d. Buying and selling can be transacted any time, any day.
e. E-commerce facilitates reaching out to more customers as theoretically, there are no
geographic limitations – nationally and internationally.
f. Low operational costs and better quality of services.
g. There is no need to set up physical company.
h. Customers can easily select products from different providers without moving around
physically.
i. Cost incurred when doing business on the global level has reduced as with e-commerce,
ones business presence on the Internet affords the business the opportunity to do
business with customers globally.
j. Improve marketing and promotion of goods and services.
k. Ecommerce enables smaller companies to compete with larger companies.
Disadvantages of ecommerce
The following are some of the disadvantages of ecommerce:
a. Businesses now find themselves in stiffer competition on the international level.
b. The move to the ecommerce requires some level of investment in hardware,
telecommunication equipment, software etc.
c. Any one, good or bad, can pretend to be doing ecommerce. There are many fraudulent
sites which cheat customers.
d. There is no guarantee of product quality or service.
e. Security – The integrity and confidentiality of some customer’s payment details have
been abused.
f. There are many hackers who look for opportunities and thus an ecommerce site,
service, payment gateways, all are always prone to attack. Thus cybercrime and security
in general are challenges.
g. The direct touch in conducting business or commerce is absent.
h. Loss of customer confidence in case of security breaches.
Impacts of E-Commerce on Business
E-commerce has impacted on business in many ways. Some of them are as follows:
a. Product promotion.
b. New sales channel (Wider market).
c. Reduced cycle time.
d. Enhanced Customer services.
e. Customization of product and services.
f. One-one or direct advertisement.
g. Technology and Organizational learning.
h. Trading online.
i. Changing nature of work.
j. Cashless and electronic payment systems.
k. Cost savings.
E-Commerce Applications
• E-Marketing
• E-Advertising
• E-Banking
• E-Learning
• Mobile Commerce
• Online Shopping
• Entertainment
E-Marketing
E-Marketing also known as Internet Marketing, Online Marketing, Web
Marketing. It is the marketing of products or services over the internet.
It is considered to be broad in scope because not refers to marketing on the
internet but also done in Email and wireless media.
E-Marketing ties together the creative and technical aspects of the internet,
including design development, advertising and sales. Internet marketing is
associated with several business models i.e., B2C, B2B, C2C. Internet marketing
is inexpensive when examine the ratio of cost to the reach of the target.
E-Advertising
It is also known as online advertising it is a form of promotion that uses internet
and World Wide Web to deliver marketing messages to attracts customers.
Example: Banner ads, Social network advertising, online classified advertising
etc.
The growth of these particular media attracts the attention of advertisers as a more
productive source to bring in consumers.
E-Banking
Means any user with a personal computer and browser can get connected to his
banks, website to perform any of the banking functions. In internet banking
system the bank has a centralized data base i.e., web-enabled. Best example for
E-Banking is ATM.
An ATM is an electronic fund transfer terminal capable of handling cash
deposits, transfer, Balance enquiries, cash withdrawals, and pay bills.
• SERVICES THROUGH E-BANKING:
Ø Bill Payment Service
Ø Fund Transfer
Ø Investing through Internet Banking
Ø Shopping
E-Learning:E-Learning comprises all forms of electronically supported learning and teaching.
E-Learning applications and processes include web-based learning, computerbased learning. Content is delivered via. The internet, intranet/extranet, audio, or
video tape, satellite TV.
E-Learning is naturally suited to distance and flexible learning, but can also be
used conjunction with face-to-face teaching.
E-Learning can also refer to the educational website such as those offering
learning scenarios worst and interactive exercises for children.
A learning management system (LMS) is software used for delivering, tracking,
and managing training /education.
Mobile Commerce
Mobile Commerce also known as M-Commerce, is the ability to conduct,
commerce as a mobile device, such as mobile phone.
Banks and other financial institutions use mobile commerce to allow their
customers to access account information and make transactions, such as
purchasing, withdrawals etc.,
Using a mobile browser customers can shop online without having to be at their
personal computer.
• SERVICES ARE:
1. Mobile ticketing
2. Mobile contract purchase and delivery mainly consumes of the sale of ring
tones, wallpapers and games of mobile phones.
3. Local base services
• Local discount offers
• Local weather
4. Information services
• News
• Sports, Scores
Online Shopping
Online shopping is the process whereby consumers directly buy goods or services
from a sell in real time, without intermediary services over the internet.
An online shop, e-shop, e-store, internet shop web shop, web store, online store,
or virtual shop evokes the physical analogy of buying products or services in a
shopping center.
In order to shop online, one must be able to have access to a computer, a bank
account and debit card.
Online shoppers commonly use credit card to make payments , however some
systems enable users to create accounts and pay by alternative means ,such as
• Cheque.
• Debit cards.
• Gift cards
Online stores are usually available 24 by 7.
Entertainment:The conventional media that have been used for entertainment are
1. Books/magazines.
2. Radio.
3. Television/films.
4. Video games.
Online books /newspapers, online radio, online television, online firms, and
online games are common place in internet where we can entertain. Online social
networking websites are one of the biggest sources of E-entertainment for today’s
tech-savvy generation.
E-COMMERCE PAYMENT SYSTEMS
E-commerce payment system provides the means for electronic payment for online
transactions. A variety of online payment systems for e-commerce are in the offering, some of
them are discussed below:
Credit Cards: A credit card is any card that may be used to borrow money or buy products
and services on credit. It is normally issued by banks, savings and loans enterprises, retail stores
and other businesses. Credit card is the most common form of payment for e-commerce
transactions. It consists of plastic card with a magnetic strip and it is portable enough to fit into
wallets or purses. Holders of a valid card have the authorization to purchase goods and services
up to a predetermined amount, called a credit limit. The vendor receives essential information
from the cardholder. The bank issuing the card actually reimburses the vendor, and eventually
the cardholder repays the bank through regular monthly payments. If the entire balance is not
paid in full, the issuer can legally charge interest fees on the unpaid portion.
Digital Wallets: A digital wallet or e-wallet is also another type of e-commerce payment
system. Much like a physical wallet, a digital wallet can store your personal information and
payment. Most wallets reside on the user's PC, but recent versions, called "thin" wallets, are
placed on the credit card issuer's server. Once the software is installed on your digital wallet,
you enter your personal information such as name and billing address, then connect it to your
banking information so you can use it to withdraw funds from your account(s) when making
on-line purchases.
E-cash: It is an Internet-based system that allows funds to be transferred electronically and
items purchased by credit card, cheque or by money order. E-cash provides secure and private
on-line transaction processing.
Mobile Payment: Another form of e-commerce payment system is mobile payment also
referred to as mobile money, mobile money transfer, or mobile wallet. With this kind of system,
a consumer uses a mobile device such as a cell phone to pay for products or services. Instead
of using cash or credit cards to buy something, the user simply sends a payment request via
text message. If the vendor has the mobile billing capability, the consumer's mobile account or
credit card is charged for the purchase.
Bank transfers.
While not everyone has a credit card, you can be sure that almost all of your customers will
have a bank account to keep their cash in.
However, despite the fact that online shopping is at an all-time high, consumers still have
concerns about security when handing over card details.
The main benefit of bank transfers is that customers don’t have to disclose any financial
details to you in order to make a purchase.
UNIT 5: SOCIAL, ETHICAL AND HEALTH ISSUES IN ICT
Introduction
ICT is a key technology of the modern era and has been central and essential to key
operations in modern industrial society, including manufacturing, transport and distribution,
government, the military, health services, education and research. Their impact of ICT on
society will most likely increased over the years
Society has become exposed to the abuse and misuse of ICT thereby creating problems such
as computer crime, software theft, hacking, viruses, invasions of privacy, an over- reliance on
intelligent machines and workplace stress, each of which has created one or more social,
ethical etc issues.
In this unit we will discuss the following which are some of the new social issues that have
come about due to ICT and its related technologies.
COMPUTER CRIME AND COMPUTER CRIMINALS
New technology brings with it new opportunities for crime, but in many ways, computers and
computer networks have left many open doors for criminal to enter.
With the advent of computers, criminals have found a new way to commit crimes. A computer
crime or cybercrime is any unlawful activity that is done using a computer and computer
network. A related word is netcrime. It refers more to criminal exploitation of the Internet.
Computer crime is the act of performing any illegal action such as stealing, embezzling or
defrauding an organization with the use of a computer. Many such crimes frequently go either
undetected or unreported. Crimes such as the following are on the increased:
i.
People are stealing or doctoring data, or threatening to destroy data to extort money
from companies.
ii.
ATMs (Automated teller machines), EFT (Electronic funds transfer), EDI (Electronic
data interchange), cellular phones are all vulnerable.
iii.
Desktop publishing has made forgery and counterfeiting easier than it used to be.
1
Reasons for Increased in Crimes
i.
Rapid technology growth
ii.
Easy availability of hacker/hacking tools
iii.
Anonymity (Unrecognizability)
iv.
Cut-and-past programming technology
v.
Communication speed
vi.
High degree of internetworking
vii.
Increasing dependency on computers
Some of the perpetrators of computer crimes are employees, hackers, crackers,
cyberextortionist and cyberterrorist.
Employees
The largest category of computer criminals is the actual employees who have been trusted with
the system and as such have easy access to the system. Newspapers are full of news about
dishonest and mischievous employees who have used computers to defraud their organizations.
Cracker
A cracker is someone who accesses a computer or network illegally and has the intent of
destroying data, corrupting program, stealing or altering data, introducing viruses and
performing other malicious actions.
Hacker
Originally the term ‘hacker’ was a complimentary word for a computer enthusiast. Now it has
a derogatory connotation with the same definition as cracker. A hacker therefore is also
someone who accesses someone’s computer or network illegally for profit and other malicious
intentions.
2
Cyberextortionist.
A cyberextortionist is someone who carries out cyberextortion. Cyberextortion is a crime
involving an attack or threat against an enterprise, coupled with a demand for money to avert
or stop the attack. Cyberextortion can take forms such as denial of service (DoS) attacks,
encrypting victim’s data, taking ‘hostage’ the ICT facilities of the victim, etc. The opportunities
of cyberextortions have increased because a number of organizations and enterprises rely on
the Internet for their business.
Cyberterrorist
A Cyberterrorist is someone who commits cyberterrorism. Cyberterrorism is any premeditated,
politically motivated attack against information, computer systems, computer programs and
data which results in physical violence or extreme financial loss against the victim.
Cyberterrorism is a also a word used to describe the use of Internet based attacks in terrorist
activities, including acts of deliberate, large-scale disruption of computer networks, especially
of personal computers attached to the Internet, by the means of tools such as computer viruses.
Cyberterrorism is sometimes referred to as electronic terrorism or information war.
Computer Fraud
Computer fraud is a computer-related crime involving deliberate misrepresentation or
alteration of data in order to obtain something of value. Computer fraud can therefore be
described as a subset of computer crime. Examples of computer crimes are:
a. Altering computer input in an unauthorized way.
b. Altering, destroying, suppressing, or stealing output, usually to conceal unauthorized
transactions.
c. Altering or deleting stored data.
d. Altering or misusing existing system tools or software packages, or altering or writing
3
code for fraudulent purposes.
Cyberwarfare
Cyberwarfare is also known as cyberwar and Cyber Warfare. It is the use of computers and the
Internet in conducting warfare in cyberspace.
Software Piracy
It is the violating of copyright on software, that is, making an illegal (unauthorized) copy of
software. With respect to software, it is illegal to download copyright-protected music and
videos from the Internet. Software piracy costs the software industry billions of dollars a year.
MALICIOUS PROGRAMS
Malicious programs known as Malware, is a contraction of two words; Malicious and Software.
It is a software designed to secretly access a computer system without the owner's informed
consent. It is a term that refers to a variety of hostile, intrusive, or annoying software. Malware
therefore includes computer viruses, worms, Trojan horses, spyware, dishonest adware,
scareware, crimeware and unwanted software or programs.
Computer Viruses
A computer virus is a computer program that can copy itself and infect a computer. When the
virus infects a computer, it can spread throughout, corrupt (damage) files, erased file, damaged
disks, and shut down computer systems and negatively alter the ways the computer works. A
virus can spread from one computer to another when the program that it has attached itself is
copied onto another computer. It can also spread through a network or carried on a removable
medium such as a CD, DVD or USB drive, or through email attachments, or programs
downloaded from the Internet or even through Internet. Viruses are sometimes wrongly used
to refer to other types of malwares such as Trojan horses, worms etc.
Worms
4
A computer worm is a self-replicating malware computer program. Unlike a virus, it does not
need to attach itself to an existing program. A worm may copy itself into the computer memory.
The key difference between a virus and worm is the manner in which it reproduces and spreads.
A virus is dependent upon the host file or boot sector, and the transfer of files between
computers to spread, whereas a computer worm can execute completely independently and
spread on its own accord through network connections.
The security threat from worms is equivalent to that of viruses. Computer worms are capable
of doing an entire series of damage such as destroying crucial files in your system, slowing it
down to a large degree or even causing some critical programs to stop working. Some examples
of worms are the MS-Blaster, Sasser worms and Internet worms.
Trojan Horse
In the field of computers, a Trojan horse is a program in which malicious or harmful code is
contained or hidden inside in such a way that it can get control and do its chosen form of
damage. The term comes from Greek mythology about the Trojan War. According to legend,
the Greeks presented the citizens of Troy with a large wooden horse in which they had secretly
hidden their warriors. During the night, the warriors emerged from the wooden horse and
overran the city.
A computer infected with malware can experience any of the following:
a. Files/programs are corrupted.
b. Files/programs disappear.
c. The speed of the computer becomes slow.
d. Systems settings or properties change.
e. Screen displays unusual message or image.
f. Music or unusual sound plays randomly.
g. Available memory is less than expected.
h. Programs or files do not work properly.
i. Unknown programs or files mysteriously appear.
5
Safeguarding Against Computer Malware
It is important to constantly check your computer and storage media for malwares. Checking
for malwares require antivirus software, which scan disks and programs to detect and eradicate
them. Antivirus software are programs that scan disks, prevent, detect and remove viruses.
Some common antivirus programs are AVG, Kaspersky, McAfee VirusScan, etc.
Because new viruses keep on appearing, it is important that you also constantly update your
antivirus software to be able to handle these new viruses. This means that you should have
proprietary antivirus software that will allow regular updates to be downloaded from the
Internet.
Though no method guarantees a computer or network is safe from malicious programs, some
of these precautions below can be taken to reduce the risk of virus infection:
a. Do not boot your computer with removable media inserted in the drives or plugged in
the ports.
b. Do not open an email attachment unless you are sure of its source.
c. Install antivirus and update it regularly.
d. Check all downloaded programs for malwares.
e. If antivirus flag email attachment as infected, delete the attachment immediately.
f. Scan for viruses before you use any removable media.
g. Install firewall.
h. Make backup copies of your important files.
HARDWARE THEFT AND VANDALISM
Hardware theft is the act of stealing computer equipment. Hardware vandalism on the other
hand is the act of defacing or destroying computer equipment. Hardware theft and vandalism
may be motivated by the perpetrator to hide evidence of fraud committed with the computer.
Precautions to prevent hardware theft include the following:
a. Use physical access controls, such as locked doors and windows.
6
b. Use cables to lock the equipment to desk, cabinet or floor.
c. Install alarm systems for additional security.
d. Never leave a notebook computer or handheld computer unattended in a public place.
e. Use passwords, possessed objects and biometrics as a method of security.
f. Back up all the files stored on the computer regularly.
SOFTWARE THEFT
Software theft is in can be categorized into three. These are stealing of software, intentionally
erasing a software and software piracy.
Stealing of Software
With this kind of software theft, the perpetrator physically steals the media that contains the
software.
Intentionally Erasing of Software
Computer vandals are fond of everything and intentionally erasing software is no exception.
Programmers also intentionally delete software that they have written in-house when they are
fired, as a form of retaliation.
Software Piracy
It is the violating of copyright on software, that is, making an illegal (unauthorized) copy of
software. With respect to software, it is illegal to download copyright-protected music and
videos from the Internet.
INFORMATION THEFT
Information theft is when someone steals confidential information. Such information can be
used to the disadvantage of the victim. An organization can buy stolen information about its
competitor. Personal information such as credit card numbers are also susceptible to theft if
they are transmitted over a network. A variety of encryption techniques are used by individuals
and companies to protect information on the Internet and networks.
7
Phishing
Phishing is a criminally fraudulent (scam) process of attempting to acquire sensitive
information such as usernames, passwords and credit card details by pretending as a
trustworthy entity in an electronic communication. Communications purporting to be from
popular social web sites, auction sites, online payment processors or IT administrators are
commonly used to lure the unsuspecting public. Phishing is typically carried out by e-mail or
instant messaging, and it often directs users to enter details at a fake website whose look and
feel are almost identical to the legitimate one. To avoid falling victim to phishing, users of the
Internet are advised to adhere to the following:
a. Never respond to an email asking for personal identification.
b. If you doubt the authenticity of a message, verify it by contacting the institution itself.
c. Avoid spoofed sites by entering web address into the browser, do not just click on link
in message.
d. Give an incorrect password first. A phishing site will accept it but a legitimate one
would not accept it.
INTELLECTUAL PROPERTY RIGHTS
Intellectual property refers to unique and original works such as ideas, inventions, writings, art,
processes, company and product names and logos. Intellectual property rights are the rights to
which creators are entitled for their work. Issues of intellectual property are of concern because
many of these works are available digitally and thus easily accessible.
Plagiarism
Plagiarism is the act of taking another person's writing, conversation, song or even idea and
using it as your own. This includes information from web pages, books, songs, television
shows, email messages, interviews, articles, artworks or any other medium.
Copyright
Copyright is a set of exclusive rights regulating the use of a particular expression of an idea or
information. A copyright gives authors and artists exclusive rights to duplicate, publish and
8
sell their materials. Copyright protects any tangible form of expression. In most cases, these
rights are of limited duration. For instance in some countries, copyright lasts for the life of the
author plus 70 years. The symbol for copyright is © or in some instances (c).
Copyright on Software
Software users’ should read software license to know their restrictions. They should also follow
the guidelines for commercial, shareware or freeware software.
Generally, the copyright law and guidelines allow users to:
a. Make one backup copy of a software program that you own.
b. Use the back-up copy only if the original fails.
c. Adapt a computer program to your use by adding to the content or adapting it to another
language. You cannot sell, distribute or transfer the adapted version of that program.
You are not allowed to:
a. Make multiple back-up copies.
b. Make one copy for home and one copy for school use.
c. Make a copy for someone.
COMPUTER OR INFORMATION PRIVACY
While the obvious benefits of computers on networks/Internet they pose potential evasion of
privacy and other privacy risks.
Privacy
The concept of privacy is narrower than security; being closely related to the idea of
confidentiality, or the need to prevent authorised disclosure of data. In the field of ICT,
information privacy refers to the right of individual or an organization to restrict or deny the
dissemination or use of information about them.
The Internet and Privacy Risk
Anyone who uses the Internet should be concerned about privacy issues since there are a lot of
programs on the net which can be tracking his/her activities or picking information about him
or her without the knowledge of the user. Some of these programs are as follows:
Cookies
9
A cookie also known as a web cookie, browser cookie, and HTTP cookie is a specialized
program that is put on your computer from the web sites that you have visited. These programs
are deposited without your knowledge and they are used to monitor your web activities. They
record the sites you visit, what you do at the sites, your preferences and other information you
provide about yourself such as passwords and credit card numbers. Most browsers are able to
control many types of cookies. You can also use cookie-cutter programs to control unwanted
cookies.
Spyware and Adware
Spyware is a type of malware that can be installed on computers and collects little bits of
information at a time about users Internet activities without their knowledge. The presence of
spyware is typically hidden from the user, and can be difficult to detect.
Web Bug
A web bug is an object that is embedded in a web page or e-mail and is usually invisible to the
user. It collects and reports information back to a predefined server on the web. One common
use is in e-mail tracking, that is, if an e-mail was read or forwarded to someone. Web bug can
be used to secretly read a user’s email messages.
Computer Monitoring
It is also known as Spy software or keylogger. This is one of the dangerous types of spyware.
It allows remote computer monitoring and keylogger recording in real time. The built-in
keystroke recorder allows the one monitoring to know everything a user types in his emails,
chats and other programs, including passwords, views and records Internet activity, trace all
programs started and run by the user. The good news is that many developers have released
anti spyware software that are dedicated to blocking or removing spyware.
Spam
Spam, also referred to as junk mail is an unsolicited mail. Sending of Spam violates acceptable
computer user policies. The content of spam ranges from advertising to offensive material.
Users can reduce the amount of spams they receive by having email filtering or installing anti-
10
spam program. The disadvantage of email filters and anti-spam program is that they mistakenly
remove valid email messages.
Tips to Protect Privacy while on the Web
a. Encrypt sensitive e-mail. Use encrypting software to encrypt your sensitive emails to
ensure that they are not readable by unauthorized people.
b. Hide your identity. Use special web sites that forward email without disclosing your
real identity.
c. Block Cookies. Use a browser that can block undesired cookies.
d. Becareful about releasing information about yourself. Do not be too generous with
information about yourself when you are online. Do not disclose your personal
information to strangers.
COMPUTER ETHICS
Computer ethics is a new branch of ethics that is growing and changing rapidly as computer
technology also grows and develops. The term ‘computer ethics’ in a very broad sense includes
standards of professional practice, codes of conduct, aspects of computer law, public policy,
corporate ethics, freedom of speech in cyberspace, intellectual property, computer crime,
software theft (piracy), information accuracy, intellectual property rights, codes of conduct and
information privacy, etc.
Information revolution has significantly altered many aspects of life - in banking and
commerce, work and employment, medical care, national defense, transportation and
entertainment. Consequently, information technology has begun to affect (in both good and
bad ways) community life, family life, human relationships, education, freedom, democracy,
and so on. As a result there is the need to have moral principles and guidelines that regulate
the use of computers. Computer ethics is concerned with standards of conduct pertaining to the
use of computers and information systems.
11
Examples of unethical computer codes of conduct include:
a. Modifying certain information on the Internet, affecting the accuracy of the
information.
b. Selling information to other parties without the permission of the owner.
c. Use information without authorization.
d. Plagiarism.
e. Pirating of software.
Netiquette
Netiquette is a contraction of Internet etiquette; the do's and don'ts of online communication.
Netiquette is a term that refers to good behavior while connected to the Internet. It is mainly
used when referring to behavior while using Internet facilities such as individual Web sites,
emails, newsgroups, message boards, chat rooms or Web communities. It thus covers rules to
maintain civility while a user is on the net.
Some examples of netiquette are listed below:
a. Not using someone else's name and pretending to be the one.
b. Not posting or distributing material that is deemed illegal.
c. Not using abusive or threatening language (avoiding flames during discussion on the
net).
d. Not posting racist remarks regarding peoples’ sex, race or gender.
e. Not spamming message boards or chat rooms with useless or repeated messages.
f. Not trying to obtain or use someone's password.
g. Not trying to obtain personal information about someone.
Usenet, mailing lists and other public posting areas have binding standards that users of those
forums should adhere. For example, netiquette advises users to use simple formats because
complex formatting may not appear correctly for all readers. Netiquette requires that people
post constructive and relevant messages on places like Usenet newsgroups. Things such as
posting messages on a different topic to the subject requested and commercial advertising are
seen as bad Netiquette. Posting messages that contain bad spelling and grammar is even seen
as bad Netiquette.
12
The Ten Commandments For Computer Ethics
1. Thou shalt not use a computer to harm other people.
2. Thou shalt not interfere with other people's computer work.
3. Thou shalt not snoop around in other people's files.
4. Thou shalt not use a computer to steal.
5. Thou shalt not use a computer to bear false witness.
6. Thou shalt not use or copy software for which you have not paid.
7. Thou shalt not use other people's computer resources without authorization.
8. Thou shalt not appropriate other people's intellectual output.
9. Thou shalt think about the social consequences of the program you write.
10. Thou shalt use a computer in ways that show consideration and respect.
COMPUTERS IN THE WORKPLACE AND THEIR HEALTH CONCERNS
Health Concern of Computer Use
Another social issues associated with the usage ICT in general is the health concerns. Users
are one of the key components in any information system. Thus protecting users against
computer related health conditions is as important as safeguarding hardware, software, data
and information. We describe below some health concerns associated with the use of
computers.
Computers and Health Risks
A repetitive strain injury (RSI) is an injury of disorder of the muscles, nerves and tendon,
ligaments and joints. Computer-related RSIs include tendonitis and carpal tunnel syndrome
(CTS). Long term computer work can lead to tendonitis or CTS. Factors that account for these
disorders include prolonged use of the keyboard and mouse as well as the shifting between the
mouse and the keyboard.
Another health-related condition due to computer usage is computer vision syndrome.
Computer vision syndrome (CVS) is a temporary condition resulting from focusing the eyes
13
on a computer display for protracted, uninterrupted periods of time. Some symptoms of CVS
include headaches, blurred vision, neck pain, fatigue, eye strain, dry and irritated eyes, double
vision, polyopia and difficulty refocusing the eyes. These symptoms can be further aggravated
by improper lighting conditions. Users of computers who spend long time sitting in front of
computers may also complain of lower back ache and fatigue, which may be due to poor
posture.
Ergonomics
Ergonomics is the study of physical relationship between people and their tools, such as their
computer. It is the science of designing the workplace environment to fit the user. Proper
ergonomic design is necessary to prevent repetitive strain injuries, which can develop over time
and can lead to long-term disability.
Ergonomics is employed to fulfill the two goals of health and productivity. It is relevant in the
design of such things as safe furniture, easy-to-use interfaces for machines, and general
working environment.
GUIDELINES FOR HEALTHY COMPUTING
Working with computers can be productive, rewarding and a lot of fun. Unfortunately,
prolonged postures, coupled with high levels of concentration and the occasional frustration of
things going less than perfectly, can lead to physical problems. Basic understanding in the way
users ‘interface’ with the computer can help prevent common health-related problems.
Knowledge of the principles of ergonomics, how people interact safely and efficiently with
machines and their work environment, can save a lot of discomfort and maximize both
productivity and enjoyment.
Set your monitor for healthy viewing
You must be able to see what you are doing easily to avoid eye strain and neck pain.
Ergonomics experts recommend that viewing angle should be about 20 degrees to the centre
of the monitor with a viewing distance of 18 to 28 inches. There should be adequate amounts
of light. Use the control knobs on the monitor to get suitable viewing. Tilt and height positions
of the monitor should be adjusted too for the user. Rearrange things and reposition yourself
14
until you can see well and feel comfortable.
Chairs
Use a chair with neck rest and arms rest. The chair should have support for the user’s lower
back also. The chair should have adjustable seat height and the user should experiment with
chair height and/or tilt. Try different chairs until you get the one that makes you feel
comfortable.
Keyboard
Keyboard users should get the right height of the keyboard to prevent too much bend at the
wrist and allow the forearm to have some support. The use of wrist rest to support your wrist
is important. A common problem associated with the use of keyboard as a result of repetitive
motions is Carpal Tunnel Syndrome. Carpal Tunnel Syndrome is considered to be a form of
repetitive stress injury.
Mouse
The continual clicking and precise motions involved in mouse use are a repetitive action that
can be a health hazard. A few basic rules can help make handling this convenient input device
safer and more comfortable:
a. Hold the mouse loosely.
b. Use your whole arm and shoulder to move the mouse, not just your wrist.
c. Keep your wrist relaxed and neutral, not bent.
d. Avoid prolonged postures.
e. Left handed users should use a "left handed" mouse, or configure the mouse to
work best with their left hand.
Desks
Make enough space so that you have room to work, especially if you are moving your mouse
around. Use a paper holder to keep letters or books at eye level. Your work space should be set
up so that you need not twist your neck. Documents should be positioned at the same height
and next to the monitor, especially if a lot of time is to be spent at these tasks. Make your work
space user friendly.
15
Posture
The posture you sit in should be comfortable to avoid back pain. Sit upright, with your knee at
an angle of 90 degrees. Footrests help, as do cushions if your chair is not providing adequate
support. The most important rule is to avoid prolonged positions. Shake your hands and
shoulders regularly.
Rest your Eyes Occasionally
Besides good lighting, the most important eye consideration is to look away from the screen
occasionally.
Take Frequent Breaks
At least once an hour, get right up off your seat and walk around, stretch, yawn, shake, breath,
get the blood flowing and stimulate the joints. It is worth the time and trouble as you will feel
better and work efficiently.
Figure 5.1: Ergonomic sitting posture
16
17
UNIT 6 COMPUTER SECURITY
Introduction
Issues about computer security, privacy and associated issues have become so paramount of
late than ever because of the fact that our society has become unduly reliant on computers to
the extent that computers’ failure totally bring to halt operations in business. Besides, today’s
computers are used to keep track and store almost every activity of humans such that there is
the need to make sure that information on the computers are always accessible at the required
times to the right user, and in an unmodified form.
COMPUTER SECURITY
Computer Security issues are important considerations in the design and operations of
information systems in an organization. Security has been defined as the protection of data
from accidental or deliberate threat which might cause unauthorised modification, disclosure
or destruction of data and the protection of the information system from the degradation or
non-availability of services as well as the protection of humans against injury and harm.
Security is thus broadly defined to incorporate the following:
•
The protection of data and programs from unauthorised change or modification.
•
The assurance that systems operate as designed, and that users continue to receive the
services that they need.
•
The protection of hardware against damage.
•
The protection of users against injury and harm arising from the use of computers.
The consequences of a breach of security may cause:
a. Loss of confidentiality (for example through hacking).
b. Loss of integrity (for example due to alteration of data by mischievous employee)
c. Loss of availability of computer services (for example due to fire outbreak).
Core Principles of Computer Security
The three key concepts that form the core principles of computer security are Confidentiality,
Integrity and Availability. These three core concepts are also referred to as the CIA triad.
1
Confidentiality
Integrity
Availability
Figure 14.1: CIA Triad
Confidentiality
It is the authorized restrictions on information access and disclosure, including means for
protecting personal privacy and proprietary information. A breach of confidentiality leads to
loss of confidentiality.
A loss of confidentiality is the unauthorized disclosure of information either accidental or
intentional. A breach of confidentiality occurs if a hacker breaks into a computer of an
organization and gets access to its database.
Integrity
It is the guarding against improper information modification or destruction, and includes
ensuring information non-repudiation and authenticity. A breach of integrity leads to loss of
integrity.
A loss of integrity is the unauthorized modification or destruction of information. A loss of
integrity occurs if an unauthorised user gets access to a system and modifies it for his or her
personal gain.
Availability
It is ensuring timely and reliable access to and use of information and computing systems. A
2
breach of availability leads to loss of availability.
A loss of availability is the disruption of access to or use of information or an information
system. A power outage can lead to loss of availability if there are no backup power systems
in place.
Threats to Computer or Information Security
Making computer and information systems secured means keeping them safe from criminals,
natural disasters and other threats. Computer and information systems are more susceptible or
vulnerable to threats. The following are some of the major threats:
a. Hardware failure.
b. Fire.
c. Software failure.
d. Electrical problems.
e. Personnel actions.
f. User Errors.
g. Technical access penetration.
h. Theft of data, services, equipment.
i. Program changes.
j. Telecommunications problem.
k. Physical damage storage media.
l. Damage to data.
m. Damage to humans.
n.
Operational problems.
o.
Industrial espionage/fraud.
p. War and Terrorisms.
CONTROLS OR MEASURES TO ENSURE COMPUTER SECURITY
To minimize errors, disasters, computer crimes and other breaches of security, special policies
and procedures must be incorporated into the design and implementation of information
systems. The combination of manual and automated measures that safeguard information
systems and ensure that they perform according to management standards is known as controls.
3
Controls therefore are methods, policies and procedures that ensure protection of the
organization’s assets, accuracy and reliability of its records, and operational adherence to
management standards. The following are some of the controls that are usually implemented.
Administrative Control
Administrative controls (also called procedural controls) consist of approved written policies,
procedures, standards and guidelines. They are thus formalized procedures to ensure that
organization’s controls are properly executed and adhered to. Administrative controls form the
framework for running the business and managing people. They inform people on how the
business is to be run and how day-to-day operations are to be conducted. They also form the
basis for the selection and implementation of logical and physical controls. Examples of
administrative controls include the corporate security policy, password policy segregation of
functions, written policies and procedures, as well as supervision.
Segregation of functions or duties ensure that an individual cannot initiate and complete a
critical task by himself. For example, an employee who submits a request for reimbursement
should not also be able to authorize payment or print the cheque. An applications programmer
should not also be the server administrator or the database administrator. These roles and
responsibilities must be separated from one another so as to minimize the risk of errors or
fraudulent manipulation for personal gains.
Administrative controls also include job rotation, IT auditing, training, awareness and
education of staff about the need and how to make the systems more secured. Human Resource
policies and hiring practices such as screening of staff to establish their character and
competence are also considered as part of administrative controls.
Logical Controls
Logical controls use software and data to monitor and control access to information and
computing systems. The use of passwords, network intrusion detection systems, access control
lists, constrained user interface are all examples of logical controls.
Physical Controls
4
Physical controls monitor and control the environment of the work place and computing
facilities. They also monitor and control access to and from such facilities. For example the use
of doors, locks, heating and air conditioning, smoke and fire alarms, fire suppression systems,
cameras, CCTV, motion detectors, barricades, fencing, security guards, cable locks. Others
such as Badges & Swipe cards, Man-Traps, Safes & Locking, Computer cases are all effective
physical control measures.
Software Controls
Software controls are built into the design of the software to monitor the use of the system and
prevent unauthorized access to the software. Some software controls are in the form of input
controls, processing controls and output controls.
Backing Up and Recovering Procedures
To prevent data loss, users of computer should regularly back up files they cannot afford to
lose and store them in a safe remote location (offsite). A backup is a duplicate or copy of a
database or program or storage media that can be used if the original is lost or destroyed. In
case of a failure of the working copy, the backup copy is recovered (restored) onto the computer
so that computer operations can continue. Organizations should have excellent backup and
recovering procedures in place.
Data Security Controls
They ensure that organization’s operational data files on storage media are not subject to
unauthorized access, change or destruction. The use of both logical access control measure
such as password and physical restriction measures are used to ensure data security.
Authentication
Computer security authentication is verifying the identity of a person logging onto a network.
It involves confirming the validity of a person in the form of identification such as a password,
PIN, passphrase, biometrics, smart cards. Multifactor authentication uses two or more
authentication such as password and fingerprint to provide increased security.
5
Encryption
Data that are transmitted over network is vulnerable to unauthorized access. An approach to
solve this problem is the use of encryption. Encryption is used to protect the confidentiality of
data in transit.
Encryption is the process of converting readable text into unreadable characters to prevent
unauthorized access. To read the text, the recipient must decrypt the encrypted (scrambled) text
into a readable form using an encryption key. Businesses and individuals use encryption
techniques to transmit confidential data and information
Firewall
A firewall is a hardware and/or software that protect a network’s resources from intrusion by
unauthorized users. All electronic communications coming into and leaving the organizations
must be evaluated by firewall before access is permitted or denied based on set of rules.
Companies use firewalls to protect network resources from outsiders and to restrict access to
sensitive data. Firewalls therefore act as security buffer between an organization’s private
network and all external networks.
Others
Security is also controlled by the use of authentication devices such as biometrics readers,
Tokens, Smart Cards, etc. Others are the use of malware guards (antivirus), IT forensics,
intrusion detection systems etc.
6