Transcript Database and Information Systems

Computers Are
Your Future
© 2005 Prentice-Hall, Inc.
Computers Are Your Future Chapter 10
Computers Are Your Future
Chapter 10
Databases and Information Systems
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
What You Will Learn About
 The potential uses of a database program
 The basic components of a database
 The basic qualities of a good database
 The differences between file management and
relational database programs
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
What You Will Learn About
 The basic characteristics of a computerized
information system
 The characteristics of valuable information
 The types of computerized information systems
 The retail sector and computer databases
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Database Concepts
Data is any unorganized text, graphics,
sounds, or videos.
A database is a collection of data.
Database programs enable people to add,
sort, group, summarize, and print data.
Information is data that has been processed in
a meaningful and useful way.
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
The Levels of Data in a Database
 The layers in a database are:
 Bits – The lowest layer made of 1s and 0s
 Characters – Letters, numbers, and symbols
 Fields – Areas that contain data identified by field names
(Examples: First Name; Address; City)
 Records – Contain a group of fields
 Data files – Contain related records
 Databases – The top layer made of one or more data files
(Example: ABC Company Address Book Mailing list, Employee
list, Vendor list)
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Computers Are Your Future Chapter 10
Data Type
 Data usually consists of text, numbers, currency, and
dates.
 Logical data – Only “yes” or “no” answers are allowed
 Objects – Non-textual data
 Binary large objects (BLOBs) – Very large objects
 Default value – Pre-defined values such as today’s date
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Types of Database Programs
 File Management Programs:
 Create flat files containing one file or table
 Files can not be linked to other files
 Are easy to use and customize
 Are not as complex as database management systems
 Database Management Systems (DBMS):
 Contain multiple files or tables
 Are programs that enable data to be stored, modified, and
extracted from a database
 Are more difficult to learn than file management systems
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Relational Database Management Systems
 Relational database management systems are the most
widely used type of DBMS.
 Data in several files are related through the use of a
common key field.
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Data Warehousing and Data Mining
 Data Warehousing:
 Supplements DBMSs by bringing together all data into one
huge database
 Organizes management’s decision-making process
 Uses a technique called drill-down to view performance
data of the entire company
 Data marts support one division of an organization rather
than an entire firm.
 Data Mining:
 Is a data exploration technique
 Is used to find unknown patterns of data
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Client/Server Database Systems
 Data server – Professionally administered program
that runs on a local area network (LAN). It responds
to requests for data.
 Client – A user-friendly program that accesses the
server. Users can add data, maintain records, perform
queries, and generate reports.
Clients request data using a query language called
Structured Query Language (SQL).
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
The Internet Connection: Going Public With Data
 Web-based integration is the latest trend in database
software.
 Information is stored in databases that are available
through the Internet.
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Advantages of Database Management Systems
 The areas of importance for building a quality
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© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Information Systems: Tools for Global
Competitiveness
 An information system is designed to bring data,
computers, procedures, and people together to manage
information important to an organization’s mission.
 To be valuable, information must be:
 Accessible
 Accurate
 Complete
 Economical
 Relevant
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Functional Divisions of an Organization
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Computers Are Your Future Chapter 10
Computerized Information Systems
 A computerized information system (CIS):
 Includes data, hardware, software, trained personnel, and
procedures
 Collects critical data, processes the data, stores the data,
and disseminates information throughout the organization
 Provides essential services to organizations, including
processing transactions and keeping exact records
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Techniques of Information Reduction
 Controlling information is important to keep people
from being overwhelmed by it.
 Control methods in an information system include:
 Routing information
 Summarizing information
 Enabling selectivity
 Eliminating unnecessary information
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Transaction Processing Systems (TPSs)
 TPSs handle an organization’s accounting needs.
 Early TPSs used batch processing systems.
 Online processing consists of entering transaction
data and viewing the results immediately.
 TPSs enable managers to make operational
decisions.
 TPSs can produce summary and exception reports.
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Management Information Systems (MISs)
 MISs are computer-based systems that support the
information needs of different levels of management.
 MISs help management make informed tactical
decisions.
 MISs work with transaction processing systems.
 MISs inform managers if their goals are being met.
 Drawbacks of MISs:
 Reports may contain unwanted information
 Information may not be available when needed
 Reams of printouts
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Decision Support Systems (DSSs)
 DSSs enable managers to ask questions that can’t be
answered by MIS reports.
 Online Analytical Processing (OLAP) enables
managers to import up-to-the-minute reports from
transaction databases.
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Executive Information Systems (EISs)
 EISs are also known as executive support systems
(ESSs).
 EISs support strategic decisions made by top level
management that will affect the entire company.
 EISs filter critical information so that trends are
apparent.
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Types of Decisions and Information Systems
for Managers
Strategic decisions
Organizational
Pyramid
Tactical decisions
Operational decisions
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Knowledge Management Systems
 Knowledge management systems are used to
capture knowledge created by employees and make it
available when needed.
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Expert Systems
 Expert systems are systems that deal with expert
knowledge in a particular area.
 Expert systems:
 Help in making decisions
 Use artificial intelligence principles
 Provide technical support for customers
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Computers and Databases in the Retail Sector
 Computers and databases are used for the checkout
process and strategic purposes.
 At the checkout counter:
Point of sale terminals are replacing the cash register.
Optical scanners read the universal product code (UPC)
label that identifies items, their costs, and any sale prices.
Credit card authorization terminals are used to process
credit card transactions by placing a call to a call center
which provides authorization numbers.
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Computers and Databases in the Retail Sector
 At the checkout counter (continued):
 Check-screening systems read the check’s account
number, then compare it with delinquent accounts.
 Signature capture systems capture a customer’s signature
on a pressure sensitive pad.
 Photo checkout systems display a customer’s photo when
a credit card is used.
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Chapter 10 Summary
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Database software transforms data into information.
Information is data that is organized to be meaningful and
useful.
A database file is made of:
Characters
Fields
Records
File management programs work with one database file.
DBMSs can work with two or more database files at a time.
A good database system contains:
Data integrity
Data independence
Data redundancy avoidance measures
Data security
Data maintenance procedures
© 2005 Prentice-Hall, Inc
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Computers Are Your Future Chapter 10
Chapter 10 Summary continued
• A computer information system provides essential services to an
organization.
• Information systems include:
Transaction processing systems (TPS)
Management information systems (MIS)
Decision support systems (DSS)
Executive information systems (EIS)
Knowledge management systems (KMS)
Expert systems (ES)
• Computers and databases provide an indispensable resource for
the retail sector.
© 2005 Prentice-Hall, Inc
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