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Invitation to Computer Science
5th Edition
Chapter 14
Electronic Commerce and Databases
Objectives
In this chapter, you will learn about:
• E-commerce
• Databases
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Introduction
• E-commerce world
– Financial transactions are conducted by electronic
means
• E-business
– Orders are processed, credit is verified, transactions
are completed, debits are issued, shipping is alerted,
and inventory is reduced, all electronically
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E-Commerce
• Do you want to:
– Broaden your customer base?
– Recapture customers you are losing to competitors
with online stores?
– Better serve your existing customer base?
– Better integrate departments/functions within your
existing business?
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The Vision Thing
• Risks involved with moving into e-commerce
– Will you just move your in-store customers online
and achieve no overall gain?
– When you expose yourself to online competition, will
you have something unique to offer?
– Does your existing customer base need or want
anything that you don’t or can’t provide in your
traditional business environment?
– Are the employees in your Shipping and Accounting
departments in agreement with this idea?
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The Vision Thing (continued)
• Costs involved
– Do you have all the necessary hardware
(computers), software, and infrastructure (network
connectivity) to host a business Web site?
– Do you have the personnel and skills you need to
build and maintain a Web site?
– Do you know the potential costs of diverting
resources away from your existing traditional
business?
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Decisions, Decisions
• First major decision
– Choose between in-house development and
outsourcing
– Are you going to use your existing staff to develop
this e-business
– Will you lease space on someone else’s commercial
Web server
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Anatomy of a Transaction
• Goals
– Draw potential customers to your site
– Keep them there
– Set up optimum conditions for them to complete a
purchase
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Figure 14.1 A Typical Online Transaction in Nine Steps
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Step 1: Getting There
• How does your potential customer learn your URL?
–
–
–
–
Conventional advertising
Obvious domain name
Search engine
Portal
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Step 2: Do I Know You?
• Cookie
– Small text file that Web server sends to user’s
browser that gets stored on the user’s hard drive
• Stateless
– No information about the exchange is permanently
retained by the server
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Step 3: Committing to an Online
Purchase
• Encryption
– Encodes data to be transmitted into a scrambled
form
• Authentication
– Process of verifying the identity of the receiver of the
data
• Spoofing
– Practice of impersonating a legitimate site for the
purposes of stealing money or stealing identity
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Steps 4 and 5: Payment Processing
Figure 14.2 Secure Site Assurance
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Steps 6–9: Order Fulfillment
• Step 6
– Once customer’s credit is approved, order entry
system must alert inventory system
• Step 7
– Contact shipping system
• Step 8
– Shipping system works with the shipping company
• Step 9
– Pick up and deliver the purchase to the customer
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Designing Your Web Site
• Taxonomy
– How information is classified and organized so
customers can easily find what they want
• Site map or a navigation bar
– Can provide a high-level overview of your site
architecture
• CRM (customer relationship management) strategy
– Improve customer satisfaction
– Build customer relationships
– Bring people back to your Web site time and time
again
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Behind the Scenes
• Middleware
– Software that allows separate, existing programs to
communicate and work together seamlessly
• Disaster recovery strategy
– What are your plans for backing up critical data?
– What is your plan to keep your online business open
even when your server fails?
– What will you do if a hacker breaks into your Web
site and steals customer information?
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Databases
• Bit
– Most basic unit of data
– Combined into groups of eight called bytes
• Fields
– Group of bytes
• Record
– Collection of related fields
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Databases (continued)
• Data file
– Stores related records
• Database
– Made up of related files
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Figure 14.3 Data Organization Hierarchy
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Figure 14.4 Records and Fields in a Single File
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Figure 14.5 One Record in the Rugs-For-You Employees File
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Database Management Systems
• Manage the files in a database
• Entity
– Fundamental distinguishable component
• Attribute
– Category of information
• Primary key
– Attribute or combination of attributes that uniquely
identifies a tuple
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Figure 14.6 Employees Table for Rugs-For-You
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Database Management Systems
(continued)
• Query languages
– Enable user or another application program to query
the database, in order to retrieve information
• Composite primary key
– Needed to identify a tuple uniquely
• Foreign key
– Key from another table that refers to a specific key,
usually the primary key
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Figure 14.7 Insurance Policies Table for Rugs-For-You
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Figure 14.8 Three Entities in the Rugs-For-You Database
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Other Considerations
• Performance issues
– Affect the user’s satisfaction with a database
management system
• To significantly reduce access time:
– Create additional records to be stored along with the
file
• Distributed databases
– Allow the physical data to reside at separate and
independent locations that are electronically
networked together
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Summary
• E-business
– Every part of a financial transaction is handled
electronically
• Opening an online store
– Requires a significant amount of planning
• Database
– Allows data items to be stored, extracted, sorted,
and manipulated
• Relational database model
– Conceptual model of a file as a two-dimensional
table
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