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Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
Digital Planet: Tomorrow’s Technology
and You
George Beekman • Ben Beekman
Tenth Edition
Digital Planet: Tomorrow’s Technology and You
Chapter 7
Database Applications and Privacy Implications
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
Chapter 7 Objectives
Explain what a database is and describe its basic structure
Identify the kinds of problems that can be best solved with database software
Describe different kinds of database software, from simple file managers to complex relational databases
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Chapter 7 Objectives (cont.)
Describe database operations for storing, sorting, updating, querying, and summarizing information
Give examples of ways in which large databases make our lives safer or more convenient
Explain how databases threaten our privacy
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The Google Guys Search for Tomorrow
• Google is one of the great success stories of the Internet.
• Handles hundreds of millions of queries a day
• Launched by two Stanford Ph.D. students
• In 2004, Google offered shares to the public.
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What Good Is a Database?
Comparable to a computerized file cabinet
Databases make it easier to:
• Store large quantities of information
• Retrieve information quickly and flexibly
• Organize and reorganize information
• Print and distribute information in a variety of ways
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Database Anatomy
• Database: organized collection of information stored in a computer
• Database program: software tool for organizing storage and retrieval of that information
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Database Anatomy (cont.) Table: collection of related information
• Record: information related to one person, product, or event
• Each discrete chunk of information in a record is a field
Field: holds different types of data:
• Numeric
• Date
• Text
• Computed
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Database Operations
Import: receive data in the form of text files
Browse: navigate through information
Query: find records that match specific criteria
Sort: rearrange records (alphabetically or numerically)
Print: reports, labels, and form letters
Export: to another program for printing
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Database Operations (cont.)
Structured Query Language (SQL):
• Standard language for programming complex queries
• Graphical user interfaces allow point-and-click queries
• Is available for most database-management systems
• Users can avoid learning a new language when working with different hardware and software systems
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Complex Queries
Can be constructed to find
• The names and location of all patients in a hospital database that are on the fifth and sixth floors
• In a database of airline flight schedules, the least expensive way to fly from Boston to San Francisco on Tuesday afternoon.
• In a politicians database, all voters who contributed over $1,000 to last year’s campaign and who wrote to express concern over high taxes since the election.
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Complex Queries (cont.) The exact method for performing a query depends
on the user interface of the database software used.
Most allow user to specify the rules of the search by filling in a dialog box or a blank on-screen form
A few (usually older) require the user to type their request using a specific query language.
For example, you might have to type
• Select * From Population
Where Sex = ‘M’ and Age > = 18 and Age < = 35
Many database programs include programming languages that allow queries to be included.
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• Get to know your search engines.
• Be specific when you search.
• Use quotes to narrow your search to exact strings
• Know your pluses and minuses. • Plus is assumed between
listed items
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• Search by site. • Site may have search box
• Be selective. • Are sites reputable? • Bad information is worse
than no information.
• Triangulate. • If at first you don’t
succeed, try another approach.
Smart Web Searching
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•Special-Purpose Database Programs On home or student PC, most of the storage is taken up
with media files Media Libraries: music and photo libraries
• Media professionals use industrial-strength databases to catalog art, photographs, and other media files
PIM (personal information manager): electronic organizer like Microsoft Outlook also includes email.
• Automates address/phone book, appt calendar, to-do list, various notes.
• May need to share group calendars
• Most smart phones include these functions.
• Software can be used to synchronize multiple platforms – Best sync software makes process simple and all-but-invisible
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Special Purpose Database Programs (cont)
GIS (geographical information systems): include geographic and demographic data in map form
• Most users familiar with MapQuest, Google Maps, etc.
• Often used in conjunction with GPS receivers to provide travel information.
• A GIS system is much more advanced than this. – Can combine tables such as customer sales list with
information from U.S. Census records to identify best location to build a new branch store.
Web databases: use XML to turn static pages into a database-driven information space
• Transforming Web into a collection of mostly static pages to a dynamic database driven information space.
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SQL statements are understood by MS Access, MS SQL Server, DB2, Oracle, Sybase, MySQL and others.
SQL is a sublanguage that: • Uses high-level, easy-to-understand statements
• Has a relational database orientation
• Is portable across a wide range of systems
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The Language of Database Queries
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Beyond the Basics: Database- Management Systems
What is a database-management system?
• A DBMS can manipulate data in a large database
Data redundancy: wastes space and may cause inaccuracies
Data consistency: all tables must contain the correct information
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Example: Student Database Management System
Student ID, grade transcripts, financial records, telephone and address information, home contact information, major and requirements to graduate, etc.
Also have course enrollment information, faculty information, etc.
Update to any data items (e.g., current academic address) must be available to all other sources.
Until recently, different offices kept separate database record systems.
• Now many use Banner, which is a front end –usually for an Oracle database system
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Beyond the Basics: Database- Management Systems (cont.)
What makes a database relational?
• Tables related – possibly over 100 tables.
• Changes in one table reflected in other tables
• Predominate model in use today
• Oracle produced the first relational database
• Almost all Fortune 500 companies use Oracle
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Database Trends
Real-time computing
• Allows instant access to information.
• Interactive processing: allows users to access data in real time
• The trend toward real-time computing is accelerated by the Internet.
• Batch processing: requires transactions to be accumulated and then fed into computers in large batches
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Database Trends Downsizing and decentralizing
• Client/server approach: uses requests to access database
• Distributed databases: spread data across networks
Distributed databases
• Spreads data across networks: Kept on several different computers rather than store it in one central site.
• Connectivity software called middleware links client and server machines and hide the interaction between those machines.
Data warehouses: large, centralized systems housing enterprise data
• Used normally in large companies and government depts 22
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Database Trends (cont.) Data mining: discovery of hidden predictive
information
• Helps to predict trends and patterns in data
• Uses statistical and artifical intelligence methods
Maintaining database integrity
• Real-time database access increases the probability of data errors.
• Accessed by everyone, not just professionals.
• Dirty data: records containing errors
• Outdated addresses, spelling errors, obsolete values
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Database Trends (cont.) Data scrubbing: eliminating dirty data
• Errors can lead to inefficiency and/or bad business decision
Object-oriented databases: store objects
• Next expected change in databases
• Every object is an instance of a class.
• The class includes the data and the operations.
• The class specifies the data that is stored as well as the operations that can be used.
• Example is a “photograph” and data includes description, photographers name, copyright status.
• Operations includes creating a thumbnail-sized copy of photo
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Database Trends (cont.)
Some companies are experimenting with a combination of relational and objective oriented databases.
Multidimensional database technology: stores data in more than two dimensions
• Based on traditional relational databases
• Data is organized in cubes.
• Provide faster access by users than traditional relational databases.
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Database Trends (cont.)
Intelligent searches • More artificial
intelligence technology • Natural language
queries possible • Contextual search tools
will classify results
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• Choose the right tool for the job. • Don’t use a large
company using a spread-sheet list manager
• Think about how you’ll get the information out.
• Start with a plan; be prepared to change your plan.
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• Make your data consistent.
• Databases are only as good as their data.
• Query with care. • You get what you ask
for, not what you intended.
Dealing with Databases
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Personal Data: All about You
Identity theft: major criminal industry
• Can be triggered by being careless online or by errors in judgment.
• Victims can face massive phone bills, threats from collection agencies, and even arrests.
• It can take years to clear up the damage from an identity theft.
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Personal Data: All about You (cont.)
Record matching: uses a unique field to combine
information from different databases
Privacy is decreasing
• Data can be transmitted almost instantly
• Workplace monitoring
• Surveillance cameras
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No Secrets: Computers and Privacy
Code of Fair Information Practices
• In early 1970s, a report to Congress
• Agencies ensure the reliability and security of information in their databases.
Privacy Act of 1974
• Broadest privacy law passed by Congress
USA Patriot Act
• Passed in response to September 11, 2001 terrorist attacks
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• Don’t give out your Social Security number.
• Don’t give away information about yourself.
• Say no to direct mail, phone, and email solicitations.
• Be stingy with your email address.
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• Say no to sharing your personal information.
• Think before you post. • Pay attention to privacy
preferences. • Mobilize technology to
protect your privacy. • If you think there’s.
incorrect or damaging information about you in a file, find out.
Your Privacy Rights
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
Summary
Database programs enable users to store, organize, retrieve, communicate, and manage large amounts of information.
There are many specialized databases such as media libraries, GIS, and PIMs.
The trend is away from large, centralized databases accessible only to data-processing staff.
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Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
Summary (cont.)
Organizations are moving toward a client/server approach that enables users to have access to data stored in servers throughout the organization’s network.
The accumulation of data by government agencies and businesses is a growing threat to our right to privacy.
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