Transcript cayf12e_ppt_12

Computers Are Your Future
Twelfth Edition
Chapter 12: Databases and Information Systems
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Databases and
Information Systems
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Objectives
• Describe the basic components of a
database.
• Describe the qualities of a good
database.
• Distinguish between file management
programs and relational database
management systems, and explain the
advantages and disadvantages of each.
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Objectives
• Differentiate between advanced database
programs and applications, such as data
warehouses, data mining, client/server
database systems, and Web-database
integration.
• List the components and main functions
of an information system.
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Objectives
• Recognize the functional divisions and
business units of an organization.
• List the major types of information
systems used in today’s organizations.
• Describe how the retail sector is taking
advantage of computer databases to
increase sales and gain a competitive
edge.
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Hierarchy(Levels) of Data
Storage
• Database
oFiles (Tables)
• Records (Rows)
oFields (Columns)
• Characters (Types)(Bytes)
oBits
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The Levels of
Data in a Database
• Database units (con’t.)
o Database
• One or more related data files/tables
o Data file (table)
• Collection of related records (rows)
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The Levels of
Data in a Database
• Database units (con’t.)
o Record
• Includes a group of related fields
• Contained in tables or data files
• Has a primary key—unique identifier for each
record
o Field
• Single unit of relative information
• Has a field name—identifies content
• Content is data type—includes items as Text,
Number, Currency, Date/Time
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The Levels of
Data in a Database
• Database units
o Character (Byte)
• A letter, number, or symbol
• Made of bytes—groups of 8 bits
• Smallest useable unit of data
o Bit
• Smallest unit of data stored by a computer
• Contains either a 1 or a 0
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The Levels of
Data in a Database
• Database
o Organized collection of related data so it is
easy to:
•
•
•
•
•
Access
Manage
Update
Group
Summarize
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The Levels of
Data in a Database
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Advantages of Database
Management Systems
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Advantages of Database
Management Systems
• Data integrity
o Data is valid
• Data validation
o Techniques used to
help prevent errors
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Advantages of Database
Management Systems
• Data independence
o Separate from applications
o Changes do not require changes in structure of
forms, reports, or programs accessing databases
• Avoiding data redundancy
o Enter data only once
o Multiple entries of the same data—a sign of a poorly
developed system
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Advantages of Database
Management Systems
• Data security
o Prevents contents from being accessed by
unauthorized users (e.g., medical records, financial
data)
o Audit trail—report of who accesses which data
• Data maintenance
o
o
o
o
Required for proper care and protection
Add records
Modify records
Delete records
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Types of Database
Programs
Database Programs
• Software used to create databases
o File management program
• Generates a flat file, meaning that there is no
relationship with fields in other files
o Database management systems (DBMS’s)
• Manage multiple tables or files
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Types of Database
Programs
• File management systems
o Useful for personal and small business needs
o Used to develop a simple computerized system for
information storage and retrieval
o Inexpensive and easy to use
o Unable to link to data stored in other files
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Types of Database
Programs
• DBMS (Database management
systems)
o
o
o
o
Connects several files or tables
Manages, accesses, stores, and edits data
Available in a variety of forms
Able to present information in reports and other
formats
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Types of Database
Programs
Popular DBMS software
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Types of Database
Programs
• DBMS classifications
o
o
o
o
Flat
Relational
Object oriented
Multidimensional
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Types of Database
Programs
• RDBMS (Relational database
management systems)
o
o
o
o
o
Most widely used class of DBMS
Primary key field used as index to locate records
Queries can be done through SQL
Data dictionary lists all tables in database
Compared to file management program, RDBMS is:
• More expensive
• More difficult to learn
• Better at controlling data redundancy
• Better at preventing potential data errors
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Types of Database
Programs
• Microsoft Access
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Types of Database
Programs
• ODBMS (Object-oriented database
management systems)
o
o
o
o
Suits media applications
Data represented as objects
Incorporate sound, video, text, and graphics
Well suited for applications such as:
• Financial portfolio risk analysis
• Design and manufacturing systems
• Hospital patient record systems
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Types of Database
Programs
• Multidimensional
databases
o Depicted as a data cube
o Dimensions typically
categories (i.e., time,
products, sales,
customers, budget, and
markets)
o Choice for online analytical
processing (OLAP)
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Types of Database
Programs
• Data warehouses
o Central location capable of storing all corporate
information
o Data available for analysis
o Helps executives make decisions
• Use drill-down method (start with summary level
and move down) to focus on specific data
o Data marts similar but support a department or
division
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Types of Database
Programs
• Data mining
o Explores and analyzes data
o Determines data patterns
helpful for making decisions
o Managers better understand
customers and market
o Can help predict future
trends
o Variation is Web mining
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Types of Database
Programs
• Client/server database systems
o Use database server software—responds to remote
users’ requests for information
o Use database client software—provides an interface
with the user
o Use queries to request information from the
database server
• Examples: ATMs and online banking
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Types of Database
Programs
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Types of Database
Programs
• Web–database integration
• Taking database information and making it accessible
via the Internet
o Google, Yahoo!, Wikipedia
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Types of Database
Programs
• Cloud computing database
• Amazon SimpleDB
• Google AppEngine Datastore
• Microsoft SQL Data Services
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Information Systems:
Tools for Global
Competitiveness
• Information
systems
o Integrate:
• People
• Hardware
• Software
• Data
• Procedures
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Information Systems:
Tools for Global
Competitiveness
• Information systems (con’t.)
o Perform many functions:
• Accepts input (data)
• Processes data into information
• Stores data
• Disseminates information throughout
organization
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Information Systems:
Tools for Global
Competitiveness
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Information Systems:
Tools for Global
Competitiveness
• Reduce information overload
o Route to appropriate users
o Summarize
o Provide information to selected people with specific
needs
o Eliminate unnecessary information
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Information Systems:
Tools for Global
Competitiveness
• Functional
divisions
o Manage core functions
of an organization
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Information Systems: Tools for Global
Competiveness
• Typical functional divisions
o Accounting
• Accounts payable, accounts receivable, cost accounting,
sales information, accounting reports
• May use spreadsheets on a client/server network
o Finance
• Forecasting, budgeting, cash management, budget
analysis, financial reports
• Spreadsheets
o Marketing and sales
• Maintaining public image and generating sales
• Spreadsheets, Databases
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Information Systems: Tools for Global
Competiveness
• Typical functional divisions (con’t)
o Human Resources
• Tracks employees
• Databases
o Production/operation
• Plans and controls processes that produce goods and
services
• Mainframe systems
o Information Systems
• System of people, data records, hardware and
software that process data and information
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Information Systems: Tools for Global
Competiveness
• Business units: Division of company,
product line or group independent of other
business units
o Use of information systems:
• Analyze markets
• Provide analysis and summary of market
information
• Review and adjust strategies
• Influence competition
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Information Systems in
Organizations: A Survey
• Transaction processing systems
o
o
o
o
Handle day-to-day accounting needs
Keeps record of every transaction involving money
Save money by automating routine recordkeeping
Batch online processing
• Management information
systems
o Provide information needed to make decisions
o Generate predefined reports
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Information Systems in
Organizations: A Survey
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Information Systems in
Organizations: A Survey
• Decision support systems
o Produce reports more specific than management
information system reports
o Enable managers to create simulations
• OLAP (online analytical processing)
• Executive information systems
o Help top-level managers make strategic decisions
o Filter critical information to show trends
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Information Systems in
Organizations: A Survey
• Knowledge management
systems
o Use information from books and experienced
individuals to assist decision making
• Expert systems
o Rely on detailed and in-depth knowledge of experts
in a specific field
o Use knowledge base to generate answers
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Information Systems in
Organizations: A Survey
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Information Systems in
Organizations: A Survey
• Retail sector
o Computers and databases not
only used for traditional
applications
• Point-of-sale (POS)
o
o
o
o
o
o
Credit card authorization
Inventory system
Check-screening system
Signature capture system
Photo checkout system
Marketing devices
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Summary
• A database is a collection of data stored
in an organized way. The units of a
database are: table or data file, records,
field, and bit.
• A good database ensures data integrity,
promotes data independence, avoids data
redundancy, ensures data security, and
provides procedures for data
maintenance.
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Summary
• File management programs, which work
with a single flat file, are easy to use and
inexpensive. A database management
system works with two or more data files
that can be related by common fields.
• Data warehouses bring data together
from many smaller databases into one
massive database. Data mining and Web
mining explore data to discover unknown
patterns.
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Summary
• Client-server database systems and Web–
database integration are examples of
Database management systems (DBMS).
• An information system includes data,
hardware, software, people, and
procedures.
• Functional divisions of an organization
include: accounting, finance, marketing
and sales, human resources, production/
operations, and information systems.
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Summary
• Information systems include: transaction
processing systems, management
information systems, decision support
systems, executive information system,
knowledge management systems, and
expert systems.
• The retail sector’s use of POS terminals,
when linked with inventory databases
and other systems such as checkscreening systems, provides businesses
with the ability to perform many business
tasks effectively.
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mechanical, photocopying, recording, or otherwise, without the prior written
permission of the publisher. Printed in the United States of America.
Copyright © 2012 Pearson Education, Inc.
Publishing as Prentice Hall
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