Web Databases

Web Databases

Databases on the World Wide Web(WWW)
Popularly known as “the web”- originally developed in Switzerland in early 1990
for biological scientist to share information.
Based on client-server architecture
•Web servers
•Files encoded using HTML
•Hyperlinks
•URL
•Web browsers (Internet Explorer & Netscape Navigator) use http
•Website – collection of HTML documents

Accessing Databases on the World Wide Web:
CGI (Common Gateway Interface) – middleware
User access approaches:
• Access using CGI scripts
􀀹 CGI - PERL or C
Drawback:
less efficiency because of grouping user’s requests not possible
• Access using JDBC
􀀹 JDBC- a name trademarked by Sun;
􀀹 Java classes - Java code capable browser - JDBC drivers
ORACLE WebServer:
pictorial representation

Challenges:
1. Object technology -> DOM
2. HTML functionality is too simple to support complex application requests ->
XML (subset of SGML)
3. Web page content can be made more dynamic
4. Support for a large number of clients coupled with reasonable response times for
queries against very large databases
5. Security


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