Transcript Retirement Incentives - Arizona State University

GIT 335
Computer Systems Technology
Lecture 8
Databases and Information Systems
Dr. Thomas Schildgen, Professor
Arizona State University
Department of
Technology Management
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Lecture 8
Introduction to Information Technology
Content taken from the McGraw Hill Textbook Chapter 8
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Databases & Information Systems
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Managing Files: Basic Concepts
• A database is a logically organized
collection of related data designed and
built for a specific purpose
• Data is stored hierarchically for easier
storage and retrieval
• Files: collections of related records
– Records: collections of related fields
• Field: unit of data containing 1 or more
characters
– Character: a letter number or special character
made of bits
» Bit: a 0 or 1
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Managing Files: Basic Concepts
• Key Field – the field that identifies a record
– Often an identifying number, such as social security
number
– Primary keys must be unique
• Keys are used to pick records out of a database
• Unique keys make records stand out from each other
• If two records had the same key, then you might not
pick the correct one
– - keys are used to sort records in different ways
– Foreign keys are fields that appear in two different tables
and are used to relate one table to another
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Managing Files: Basic Concepts
This example
shows a sample
database in
Microsoft
Access.
Products is a
table. ProductID
is the primary
key of the
Product table.
ProductID is
also a foreign
key in the
Orders table
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Managing Files: Basic Concepts
• Program files are files containing software
instructions
– Source program files are written by the software
developer in the programming language
• Double-clicking on them won’t run them
• They have file extensions like .cpp, .jav, .bas
– Executable files are program files translated so they can
be executed on the computer
• Double-clicking on them will cause them to run
• They have file extensions like .exe or .com
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Managing Files: Basic Concepts
• Data files are files that contain data such
as words, numbers, pictures, or sounds
–
–
–
–
–
These are the files that are used in databases
They have extensions such as .txt .mdb, and .xls
Graphics files have extensions like .tiff, .jpeg, and .png
Audio files have extensions such as .mp3, .wav, and .mid
Animation/video files have extensions such as .qt, .mpg,
.avi, and .rm
• Data files are often compressed to save
space and transmit them faster
– Compression removes repetitive elements from a file
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Database Management Systems
• Software written specifically to control the structure of a
database and access to the data
– Reduced data redundancy
• Redundant data is stored in multiple places, which
causes problems keeping all the copies current
– Improved data integrity
• Means the data is accurate, consistent, and up to date
– Increased security
• Limits who can create, read, update, and delete the
data
– Ease of data maintenance
• Offer validation checks, backup utilities, and
procedures for data inserting, updating, and deletion
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Database Management Systems
3 Principal Components
• Data Dictionary
– A repository that stores the data definitions and
descriptions of the structure of the data and the database
• DBMS Utilities
– Programs that allow you to maintain the database by
creating, editing, deleting data, records, and files
– Also include automated backup and recovery
• Report Generator
– Program for producing an on-screen or printed
document form all or part of a database
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Database Management Systems
Database Administrator
• Database Administrator (DBA)
– A high-paid, responsible position within an organization
– Coordinates all related activities and needs for an
organization’s database
– Ensures the database’s
• Recoverability
Did you know that 93% of
• Integrity
companies that lost their data
• Security
center for 10 days or more due
• Availability
to a disaster filed for bankruptcy
• Reliability
within a year?
• Performance
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Database Models
• Hierarchical
database
• Network database
•
•
• Relational database •
• Object-oriented
database
•
• Multidimensional
database
•
Fields or records are arranged in a family
tree, with child records subordinate to
parent or higher-level records
Like a hierarchical database, but each
child record can have more than one
parent record
Relates, or connects, data in different
files through the use of a key, or
common data element
Uses objects (software written in small,
reusable chunks) as elements within
database files
Models data as facts, dimensions, or
numerical measures for use in the
interactive analysis of large amounts of
data
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Database Models
•
Hierarchical Databases
– Fields or records are arranged in related groups resembling a
family tree with child (low-level) records subordinate to parent
(high-level) records
– Root record is the parent record at the top of the database, and
data is accessed through the hierarchy
– Oldest and simplest; used in mainframes
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Database Models
•
Network Database
– Similar to a hierarchical database, but each child record can
have more than one parent record
– Used principally with mainframe computers
– Requires the database structure to be defined in advance
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Database Models
• Relational Database
– Relates or connects data in different files through the
use of a key, or common data element
– Examples are Oracle, Informix, Sybase
– Data exists independently of how it is physically stored
– Users don’t need to know data structure to use the
database
– Uses SQL (structured query language) to create, modify,
maintain, and query the data
– Query by Example uses sample records or forms to allow
users to define the qualifications for choosing records
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Database Models
• Object-oriented Databases
– Use “objects”, software written in small, manageable
chunks, as elements within data files
– An object consists of
• Data in any form, including audio, graphics, and video
• Instructions on the action to be taken with the data
– Examples include FastObjects, GemStone, Objectivity
DB, Jasmine Object Database, and KE Texpress
– Types include
• Web database
• Hypermedia database
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Database Models
• Multidimensional Database
– Models data as facts, dimensions, or numerical
answers for use in the interactive analysis of
large amounts of data for decision-making
purposes
– Allows users to ask questions in colloquial
English
– Use OLAP (Online Analytical Processing)
software to provide answers to complex
database queries
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Data Mining
• Is the computer-assisted process of sifting through and
analyzing vast amounts of data to extract hidden patterns
and meaning and to discover new knowledge
• Data is fed into a Data Warehouse through the following
steps
– Identify and connect to data sources
– Perform data fusion and data cleansing
– Obtain both data and meta-data (data about the data)
– Transport data and meta-data to the Data Warehouse
• Data Warehouse is a special database that shows detailed
and summary data from multiple sources
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Data Mining
• Methods for searching for patterns in the
data and interpreting the results
– Regression analysis
• Develops a formula to fit patterns in the data that has
been extracted
• Formula is applied to other data sets to predict future
trends
– Classification analysis
• A statistical pattern recognition process that is
applied to data sets with more than just numerical
data
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Data Mining
• Applications include
– A phone company identifying customers with
large bills, who were really small businesses
trying to pay the cheaper residential rate
– A coach in the Gymnastics Federation used it
to discover what long-term factors contributed
to athletes’ performance
– Retail stores use it to predict future purchase
patterns to help them choose which products
to stock for the future
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Databases & The Digital Economy
• E-Commerce
– The buying and selling of products and
services through computer networks
– Examples of some e-tailers (electronic
retailers):
• www.amazon.com sells books and music
online
• www.sees.com sells candy online
• www.ebay.com connects buyers with sellers
online using online auctions
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Databases & The Digital Economy
• Innovative e-tailer technologies make
online shopping easier
– 360-degree images
• Allow you to see all sides of an item
– Order tracking
• Bar codes are assigned to items being
shipped that allow customers to check
shipping progress via the internet
– Shop bots
• Are programs that help users search for a
particular product of service
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Databases & The Digital Economy
• Types of E-Commerce
– Business-to-business (B2B)
• A business sells to other businesses using the
internet or a private network to cut transaction costs
and increase efficiencies
– Business-to-consumer (B2C)
• A business sells goods or services to consumers
– Consumer-to-consumer (C2C)
• Consumers sell goods or services directly to other
consumers with the help of a third party, such as
eBay.
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Using Databases to Help Make
Decisions
• What are the qualities of good
information?
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Correct and verifiable
Complete yet concise
Cost effective
Current
Accessible
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Using Databases to Help Make
Decisions
• Most organizations have 6 departments to
which information must flow
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Research and development
Production (operations)
Marketing and sales
Accounting and finance
Human resources (personnel)
Information systems (IS)
• Information flows horizontally between
departments
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Using Databases to Help Make
Decisions
• Besides the 6 departments, many organizations also have 3
levels of management
– Strategic-level management
• Top managers concerned with strategic or long-term
planning and decisions
– Tactical-level management
• Middle level managers who make decisions to
implement the strategic goals set for the organization
– Operational-level management
• Low-level supervisors make daily operational
decisions
• Information flows vertically between management levels
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Using Databases to Help Make
Decisions
• Decentralized Organizations – a new
structure
– Employees increasingly telecommute – some staff have
no desk or office at work
– Employees communicate with each other more via email
than in person
– Companies use Groupware CSCW (computer-supported
cooperative work) systems to enable cooperative work
by groups of people
– The management structure is flattened as employees are
given more authority to make day-to-day decisions
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Using Databases to Help Make
Decisions
•
6 computer-based information systems
– Office information systems
– Transaction processing systems
– Management information systems
– Decision support systems
– Executive support systems
– Expert systems
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Using Databases to Help Make
Decisions
• Transaction Processing System (TPS)
– Transactions are recorded events of routine
business activities such as bills, orders, and
inventory
– TPS systems keep track of the transactions
needed to conduct a business
– TPS systems are used by operational managers
to track business activities
– Transactions database provides the basis for
management information systems and decision
support systems
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Using Databases to Help Make
Decisions
• Management Information Systems (MIS)
– Computer-based information system that uses data
recorded by a TPS as input to programs that produce
routine reports as output
– Features
• Inputs are processed transaction data. Outputs are
summarized structured reports
• Designed for tactical managers
• Draws from all departments
• Produces several kinds or reports: summary,
exception, periodic, and demand
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Using Databases to Help Make
Decisions
• Decision Support Systems (DSS)
– Computer information system that provides a flexible
tool for analysis and helps management focus on the
future
– Features
• Inputs are external data and internal data such as
summarized reports and processed transaction data.
Outputs are demand reports
• Mainly for tactical managers
• Produces analytic models
– Developed to support the types of decisions faced by
managers in specific industries
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Using Databases to Help Make
Decisions
• Executive Support Systems
– An easy-to-use DSS made especially for strategic
managers to support strategic decision-making
– Might allow executives to call up predefined reports
– Includes capability to browse through summarized
information on all aspects of the organization and drill
down for detailed data
– Allows executives to perform “what-if” scenarios
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Artificial Intelligence
• Expert System
– One of the most useful applications of Artificial Intelligence (AI)
– AI is a group of related technologies used to develop software
and machines that emulate human qualities such as learning,
reasoning, communicating, seeing, and hearing
– Areas include
• Expert systems
• Natural language processing
• Intelligent agents
• Pattern recognition
• Fuzzy logic
• Virtual reality and simulation devices
• Robotics
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Artificial Intelligence
• Three components of an expert system
– Knowledge base
• An expert system’s database of knowledge about a
particular subject
– Inference engine
• The software that controls the search of the expert
system’s knowledge base and produces conclusions
– User interface
• The display screen the user used to interact with the
expert system
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Artificial Intelligence
• Natural language processing
– Allows users to interact with a system using normal
English
– The study of ways for computers to recognize and
understand human language
• Intelligent agents
– A form of software with built-in intelligence that monitors
work patterns, asks questions, and performs work tasks
on your behalf
• Pattern recognition
– Involves a camera and software that identify recurring
patterns in its vision and maps the pattern against
patterns stored in a database
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Artificial Intelligence
• Fuzzy logic
– A method of dealing with imprecise data and uncertainty,
with problems that have many answers rather than one
– Has been applied in running elevators to determine
optimum times for elevators to wait
• Virtual reality
– A computer-generated artificial reality that projects a
person into a sensation of 3-D space
– Often used with simulators to represent the behavior of
physical or abstract systems
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Artificial Intelligence
• Robotics
– The development and study of machines that can
perform work that is normally done by people
– Commonly found in manufacturing plants and also in
situations where people would be in danger
• Nuclear plants
• Assembly lines, especially paint lines
• Checking for land mines
• Fighting oil-well fires
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Artificial Intelligence
• Weak vs. Strong A.I.
– Weak A.I. claims computers can be programmed to
simulate human cognition
– Strong A.I. claims that computers can think on a level
that is equal to or better than humans, and can also
achieve consciousness
• Cyc approach to strong A.I.
– A database in Austin, TX that holds 1.4 million
basic truths
– Plan is that Cyc will automatically make humanlike assumptions
– Hope is that Cyc will learn on its own
• Cog approach to strong A.I.
– MIT project that is a humanoid robot
– Tries to identify and search for patterns instead of
following rules and facts
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Artificial Intelligence
• Test for Human Intelligence
– In 1950, Allen Turing predicted computers would be able to
mimic human thinking
– The Turing test determines whether the machine is human
• Judge is in another location and doesn’t see the computer
• If the computer can fool the judge, it is said to be
intelligent
– Ethics in A.I.
• Prof. William Wallace from R.P.I. says that computer
software is subtly shaped by the ethical judgments of its
creators
• For example, H.M.O. software used by health insurers
steers doctors to cheaper procedures – but are they
better?
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The Ethics of Using Databases
• Identity Theft concerns
– A crime in which thieves hijack your identity and use
your good credit rating to get cash, take out loans, order
credit cards, and buy things in your name
• Privacy concerns
– Name migration: getting endless junk mail and
telemarketing calls
– Résumé rustling and online snooping
– Government prying and spying
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