Chapter 14
Database Connectivity and Web Development
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In this chapter, you will learn:
• About the different database connectivity technologies
• How Web-to-database middleware is used to integrate
databases with the Internet
• What Extensible Markup Language (XML) is and why
it is important for Web database development
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Database Connectivity
• Refers to mechanisms through which
application programs connect and communicate
with data repositories
• Database connectivity software is also known
as database middleware
• Data repository, also known as data source
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ODBC, DAO, and RDO
• Open Database Connectivity (ODBC)
• Microsoft’s implementation of a superset of SQL
Access Group Call Level Interface (CLI) standard
for database access
• Probably most widely supported database
connectivity interface
• Allows any Windows application to access relational
data sources, using SQL via standard application
programming interface (API)
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ODBC, DAO, and RDO
• Data Access Objects (DAO)
• Object-oriented API used to access MS Access, MS
FoxPro, and dBase databases from Visual Basic
programs
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ODBC, DAO, and RDO
• Remote Data Objects
(RDO)
• Higher-level objectoriented application
interface used to access
remote database servers
• Was optimized to deal with
server-based databases,
such as MS SQL Server,
Oracle, and DB2
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Internet Databases
• Web database connectivity allows new
innovative services that:
• Permit rapid response to competitive pressures by
bringing new services and products to market
quickly
• Increase customer satisfaction through creation of
Web-based support services
• Yield fast and effective information dissemination
through universal access from across street or
across globe
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Web-to-Database Middleware:
Server-Side Extensions
• Also known as Web-todatabase middleware
• Program that interacts
directly with Web server to
handle specific types of
requests
• Provides its services to
Web server in way that is
totally transparent to client
browser
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The Web Browser
• Software that lets users
navigate (browse) Web
• Located in client
computer
• End-user interface to
World Wide Web
• Interprets HTML code
received from Web
server
• Presents different page
components in
standard way
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Client-Side Extensions
• Add functionality to Web browser
• Following three general types:
• Plug-ins
• Java and JavaScript
• ActiveX and VBScript
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IGNORE….
Ignore Section on ColdFusion
IT will not be examined
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The Web as a Stateless System
• Stateless system indicates that at any given
time, Web server does not know status of any
of clients communicating with it
• Client and server computers interact in very short
“conversations” that follow request-reply model
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Extensible Markup Language
(XML)
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XML Presentation
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XML Presentation (continued)
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XML Presentation
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XML Applications
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B2B exchanges
Legacy systems integration
Web page development
Database support
Database metadictionaries
XML databases
XML services
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Summary
• Database connectivity refers to the mechanisms
through which application programs connect and
communicate with data repositories
• Database access through the Web is achieved
through database-to-middleware software
• Extensible Markup Language (XML) facilitates the
exchange of B2B and other data over the Internet
• XML provides the semantics that facilitates the
exchange, sharing, and manipulation of structured
documents across organizational boundaries
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