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Eurocall
' 99
Université
de Franche-Comté, Besançon, France
September 15-18, 1999 |
Understanding,
using and creating web-enabled databases
Wednesday, September 15 from 09:30 to 17:00
Room 27, PropŽdeutique, 3rd floor
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Conceptualizing
web-enabled databases
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What
is a Web-Enabled Database?
Databases are a perfect medium for managing information (Ashenfelter, 1999, p. 6).
Web-enabled databases can be used for a) dynamic publishing, b) information transactions,
and c) data storage and analysis. A web-enabled database
is a database that can be accessed through a web page. The information
stored in a database can be searched, updated, and displayed
in a web browser on the fly. Hence, HTML pages generated dynamically with the help of a database will display the most current information available.
Moreover, when the layout needs to be modified, there is no need to modify a huge number of web pages. Only one modification will usually be sufficient and the items/data displayed will have the new look you want.
A web-enabled database
requires three essential components: A Database, A Web Server,
and an Application Server.
Terminology:
What is a Database?
A database is a
software program used for the collection of organized data.
Examples: Oracle,
Microsoft Access, FileMaker Pro, Paradox
What is a Web
Server?
A web server is
hardware and software used to manage client requests (usually
from a web browser) and to return documents (usually web pages)
to the client.
Examples: Apache,
Internet Information Server (IIS), O'Reilly, NCSA Server,
WebStar , FileMaker Pro
What is a Web
Application Server?
An application
server is primarily used to manage client connections and
direct traffic for incoming client requests to database resources.
Examples: Tango,
Lasso, Cold Fusion, ASP
What is SQL?
SQL is a syntax
for developing database queries.
What is ODBC?
While SQL provides
a common syntax for query building, there still needs to be
a protocol that can take that standard syntax and translate
it into the native procedure calls to actually perform the
query. The Open Database Connectivity (ODBC) standard provides
an abstraction layer between the application interface and
the database, which effectively hides the differences and
peculiarities of each specific database. (2)
How things work together?
Browser <-->
Web Server
<--> CGI
<-->
FileMaker Pro
A browser submits
a request to a web server to fulfill. All a web server does
is fetch files from the hard disk. For database calls, it
hands it off to a CGI to query the database. Once the results
are returned from the database, the CGI then wraps HTML around
the results which it then hands off to the web server which
ultimately returns the result to the browser. At no point
is the CGI talking directly to the browser. If there are page
view problems between different browsers, it is usually in
the HTML code as defined by the programmer.
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References:
1) Database-Driven
Websites 03/15/98
http://databases.miningco.com/library/weekly/aa031598.htm?pid=2827&cob=home
Here are the first steps you will need to take in building a
database driven website, from your About.com Guide
2) Getting
Started with Web Databases by John Paul Ashenfelter Feb.
26, 1999
http://webreview.com/wr/pub/1999/02/26/webdb/index.html
Introducing the WebDB column for Web Review. John Paul discusses
the types of databases and some of the more common application
servers available to Web developers.
3) SQL
Tutorial
http://www.geocities.com/ResearchTriangle/Node/9672/sqltut.html
4) ODBC
Primer
http://www.filemaker.com/products/filemakerpro/odbc-overview.html
5) What
Do Application Servers Really Do? by Steve Benfield Feb,
1999 http://webreview.com/wr/pub/1999/02/26/appservers/index2.html
6) Opportunities
and options for Web-enabled databasees: comparing in choosing
the right software for virtual courses and communities by
Chong Ho Yu, Ph.D., CNE, MCSE, Arizona State University; Angel
Jannasch-Pennell, Ph.D., Arizona State University; Samuel A.
DiGangi, Ph.D., Arizona State University
International Journal of Educational Technology (vol 1 no 1)
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