Information Technology 104

Technology Guide 3

Data & Databases

2

File Management
Key file management concepts include:
 Database
 Bit
 Entity
 Byte
 Field  Attribute
 Record  Key field
 File

3

Hierarchy of Data

4

Accessing Records from Computer
Files
 In sequential file  In direct or random file
organization: organization:
Data records must be Users can access records
retrieved in the same in any sequence, without
physical sequence in regard to actual physical
which they are stored. order on the storage
medium.

5

Problems Arising in the File
Environment
• Data redundancy: The same piece of information
could be duplicated in several files.
• Data inconsistency: The actual values across
various copies of the data no longer agree.

• Data isolation. Data files are likely to be organized
differently, stored in different formats, and often
physically inaccessible to other applications.
• Security: is difficult to enforce in the file
environment.

6

Problems Arising in the File
Environment
• Data Integrity: It is difficult to place data integrity
constraints across multiple data files.
• Application/ Data independence: In the file
environment, the applications and their associated
data files are dependent on each other.
• The numerous problems arising from the file
environment approach led to the development of
databases.
– Database: an organized logical grouping of related
files.

7

Database Management Systems
• The program (or group of programs) that provides access to a
database is known as a database management system (DBMS).
• There are many specialized databases, depending on the type or
format of data stored.
– A geographical information database contains
locational data for overlaying on maps or images.
– A knowledge database stores decision rules used
to evaluate situations and help users make
decisions like an expert.
– A multimedia database stores data on many
media—sounds, video, images, graphic animation,
and text.

8

Database Management Systems (cont.)
Three major components of a DBMS:

 Data definition language

 Data manipulation language

 Data dictionary

9

Data Definition Language (DDL)
• DDL is the language used by programmers to
specify the content and structure of the database.
• A DBMS user defines views or schemes using the
DDL.

– A schema - the logical description of the entire
database and the listing of all the data items and the
relationships among them.

– A subschema - the specific set of data from the
database that is required by each application.

10

Data Manipulation Language (DML)
• DML is used with a third- or fourth-generation
language to manipulate the data in the database.

• DML provides users with the ability to retrieve, sort,
display, and delete the contents of a database.

• Requesting information from a database is the most
commonly performed operation.
– Structured query language (SQL)
– Query-by-example (QBE)

11

Data Dictionary
• Data Dictionary is a file
that stores definitions
of data elements and
data characteristics
such as usage, physical
representation,
ownership,
authorization, and
security.
– A data element
represents a field.

12

Logical Data Organization
There are three basic
models for logically Three additional models
structuring databases: are emerging:
 Hierarchical
 Multidimensional
 Network
 Object-oriented
 Relational
 Hypermedia

13

The Hierarchical Model
 The hierarchical model relates data by rigidly
structuring data into an inverted “tree” in which
records contain two elements:
1. A single root or master field, often called a key, which
identifies the type location, or ordering of the
records.
2. A variable number of subordinate fields that defines
the rest of the data within a record.
 The hierarchical structure is commonly found in
many traditional business organizations and
processes.

14

The Networked-based Model
 The network model creates relationships among
data through a linked-list structure in which
subordinated records (members) can be linked to
more than one owner.
 Explicit links, called pointers, are used to link
subordinates and owners. That relationship is called
a set.
 Many-to-many relationships are possible with a
network database model—a significant advantage
of the network model over the hierarchical model.

15

The Relational Database Model
 The relational model is based on a simple concept of
tables in order to capitalize on characteristics of rows
and columns of data, which is consistent with real-world
business situations.
– Tables are called relations, and the model is based on the
mathematical theory of sets and relations.
– A row is called a tuple, and a column is called an attribute.

 One of the greatest advantages of the relational model
is its conceptual simplicity and the ability to link records
in a way that is not predefined.

16

Creating Databases
• To create a database, designers must develop both
a conceptual and physical design:
– Conceptual design - an abstract model of the database
from the user or business perspective.
• Describes how the data elements in the database are to be
grouped.
– Physical design shows how the database is actually
arranged on direct access storage devices.

• Groups of data are organized, refined, and
streamlined until an overall logical view of the
relationships among all of the data elements in the
database appears.
17

Chapter 2
Information Technologies:
Concepts & Management

18

Learning Objectives
 Describe strategic information systems (SIS) and explain
their advantages.

 Describe Porter’s competitive forces model & how IT
helps companies improve their competitive positions.

 Describe Porter’s value chain model and its relationship
to information technology.

 Describe several other frameworks that show how IT
supports the attainment of competitive advantage.

19

Learning Objectives (cont.)
 Describe and understand the role of web-based SIS and the
nature of competition in the digital age.

 Describe global competition and its SIS framework.

 Describe representative strategic information systems and
the advantage they provide to organizations.

 Discuss implementation issues including possible failures of
SIS.

20

Case: Building an e-Business at Fed
Ex
Problem:
 FedEx has kept looking ahead at every stage for opportunities to meet
customers’ needs for fast, reliable, and affordable overnight deliveries.
Solution:
 In addition to e-Shipping Tools, FedEx is now providing integrated
solutions to address the selling & supply chain needs of its customers.
Results:
 FedEx’s e-business model facilitates better communication and
collaboration between the various parties along the supply chains.
 It promotes efficiency gains by reducing costs & speeding up the order
cycle.
 It transforms organizations into high performance e-businesses.

21

Characteristics of Information
Systems
 Several different information  Interorganizational information
systems can exist in one systems involve information flow
organization. in two or more organizations.

 A particular information system
 An enterprise wide system or
may be composed of several
interorganizational information
separate information systems.
system is composed of large &
 Information systems are small computers & hardware
connected by means of connected by different types of
electronic networks. networks.

22

Data, Information & Knowledge
One of the primary goals of Information Systems is to economically process data
into information or knowledge.

Data items refer to an elementary description of things,
events, activities, and transactions that are recorded,
classified, and stored, but not organized to convey any
specific meaning.

Information is data that have been organized so that they
have meaning and value to the recipient.

Knowledge consists of data or information that have
been organized and processed to convey understanding,
experience, accumulated learning, and expertise.
23

Effectiveness and Efficiency
• ISs can help companies attain more effective and
efficient business processes
– Effectiveness
• The degree to which a task is accomplished

– Efficiency
• Determined by the relationship between resources
expended and benefits gained in achieving a goal

24

Effectiveness and Efficiency (Cont.)

25

Classifications of Information
Systems
Information Systems can be classified
according to;

 Organizational Structure
 Functional Area
 Support Provided
 System Architecture
 Activity Supported

26

Classification by Organizational Structure
• Departmental information systems. Frequently, an organization
uses several application programs in one functional area or
department.

• Enterprise information systems (EIS). While a departmental IS is
usually related to a functional area, the collection of all
departmental applications when combined with other functions’
applications comprises the enterprise wide information system.

• Interorganizational systems. Some information systems connect
several organizations.

27

Classification by Functional Area
The major functional information systems are the following:

The accounting information system
The finance information system
The manufacturing (operations/production)
information system
The marketing information system
The human resources management
information system

28

Classification by Support Provided

The major types of systems under this classification are:
 Transaction processing system (TPS)
 Management information system (MIS)
 Knowledge management system (KMS)
 Office automation system (OAS)
 Decision support system (DSS)
 Enterprise information system (EIS)
 Group support system (GSS)
 Intelligent support system

29

Evolution of Support Systems
Early 1950s Transaction processing system (TPS)

1960s Management information systems
(MISs)

Late 1960s
Office automation system (OAS)
Early 1970s
Decision support system (DSS)

30

Evolution of Support Systems (cont.)
Early 1980s Executive information systems
Enterprise information systems (EISs)
Group support systems (GSSs)
Mid- 1980s Expert systems (ES)
Knowledge management systems
(KMS)
1990s Artificial neural networks
(ANNs)

31

Case: Detecting Bombs with ANN
Problem:
• The Federal Aviation Administration (FAA) use statistical analysis and
expert systems to prevent terrorists from sneaking bombs aboard
airplanes. Yet, these technologies cannot detect all types of
explosives.
Solution:
• Since 1993, artificial neural networks (ANN) have been added to
improve detection effectiveness.
• The ANN is exposed to a set of historical cases and is then able to
predict the existence of explosives in new cases.
Results:
• The FAA hopes to detect explosives more successfully and also
minimize false alarms.

32

Interrelated Support Systems

Non Computer
Support
Transaction MIS DSS
Processes

External Data EIS
Information Warehouse

Non Computer
Support
Internet, other
Computer Support

33

Classification by System Architecture

Information systems can be classified according to three
types of architecture:

A mainframe-based system.

A standalone personal computer (PC).

A distributed or a networked computing
system (several variations exist).

34

Transaction Processing
• Transaction processing systems (TPS) support the monitoring,
collection, storage, processing, and dissemination of the
organization’s basic business transactions.

– They provide the input data for many applications involving other
support systems.
– The transaction processing systems are considered critical to the
success of any organization.
– The TPS collects data continuously, frequently on a daily basis, or
even in “real time”.

35

Functional MISs
 Functional Management Information Systems (MISs) are put in place
to ensure that business strategies come to completion in an efficient
manner.

 Typically a functional MIS provides periodic information about such
topics as operational efficiency, effectiveness, and productivity by
extracting information from the corporate database and processing it
according to the needs of the user.

 MISs can be constructed in whole or in part by end-users.

 MISs are also used for planning, monitoring, and control.

36

Functional MISs
Sales forecast by region generated by marketing MIS.

37

Classification by the Activity
Supported
 Another important way to classify information systems is by the
nature of the activity they support. Such support can be:
– Operational
– Day-to-day operations of an organization
– Managerial
– Middle-management activities such as short-term
planning, organizing, and control
– Strategic
– Decisions that significantly change the manner in which
business is being done

38

Traditional Transaction Processing Methods

• Batch processing – method of computerized
processing in which business transactions are
accumulated over a period of time and prepared for
processing as a single unit

• On-line transaction processing (OLTP) - method of
computerized processing in which each transaction is
processed immediately and the affected records are
updated

39

Batch versus On-Line Processing

40

Integration of a Firm’s TPSs

41

Transaction Processing Activities

• Data collection
• Data editing
• Data correction
• Data manipulation
• Data storage
• Document production and reports

42

Data Processing Activities Common in
Transaction Processing Systems

43

Point-of-Sale Transaction System

44

New Strategic Systems
• Electronic commerce (EC) has become a new way of
conducting business in the last decade or so.
– In this new model, business transactions take place via
telecommunications networks, primarily the Internet.
– e-Commerce provides organizations with innovative and
strategic advantages, such as;
• Increased market share
• Better ability to negotiate with suppliers
• Better ability to prevent competitors from entering into
their territory

45

Information Systems & People

46

Information Infrastructure
There are five major components of the infrastructure:
 Computer hardware
 Development software
 Networks and communication facilities
(including the Internet and intranets)
 Databases
 Information management personnel

47

Information Architecture
 Information architecture is a high-level map or plan of the
information requirements in an organization.

 In preparing information architecture, the designer requires two
kinds of information:
1. The business needs of the organization—that is, its objectives
and problems, and the contribution that IT can make.
2. The information systems that already exist in an organization
and how they can be combined among themselves or with
future systems to support the organization’s information
needs.

48

Types of Information Architecture
 Mainframe environment. In the mainframe environment, processing is
done by a mainframe computer.
– The users work with passive (or “dumb”) terminals,
which are used to enter or change data and access
information from the mainframe.

 PC environment. In the PC configuration, only PCs form the hardware
information architecture.

 Networked (distributed) environment. Distributed processing divides
the processing work between two or more computers.

49

Information Technology 104

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