Database-Driven Websites

Blogs, Wikis, Etc.

What is `The Web'?

A distributed document delivery service implemented using application-level protocols on the InternetA tool for collaborative writing and community buildingA framework of protocols that support e-commerceA network of co-operating computers interoperating using HTTP and related protocols to form a sub-net of the InternetA large, cyclical, directed graph made up of webpages and links

What is `The Web'?

A distributed document delivery service implemented using application-level protocols on the Internet

A tool for collaborative writing and community A tool for collaborative writing and community buildingbuildingA framework of protocols that support e-commerceA network of co-operating computers interoperating using HTTP and related protocols to form a sub-net of the InternetA large, cyclical, directed graph made up of webpages and links

Databases and the WWW

B2B is important– Using the WWW as a distributed document

delivery service– Using XML and XML-based tools to

package and share data, place orders, maintain inventory, …

Self-organizing communities are another, but less obvious application of the WWW

Self Organizing Communities?

The standard HTML model is– Author/designer makes a webpage or website– The author decides what the content is and where

the links are• Links out of website• Link targets in the website

– Reader uses the website but cannot change it• Only input is through forms (or hacking)• More like reading a magazine than using a ‘shared

space’

Self Organizing Communities

Radical compared to HTML Model– People who come together to create a linked set

of webpages– Could also be a MUD or a MOO (although much

less frequent than before)

Types of communities– SparrowWeb – community shares templates– Wiki – multiple authors– Blog – author and commentators

Where is the Database?

It is hidden on the server-side– We infer its presence but it is not really

needed– Type, schema, etc. are unimportant

It is not an interface component– The author might not even know about it

What is a Blog?

http://jilltxt.net/archives/blog_theorising/final_version_of_weblog_definition.html

http://www.gyford.com/phil/writing/2003/01/05/an_introduction_.php

Who cares?– Part of the societal changes brought about by the WWW– New applications of hypertext– Opportunity for study within (and outside of) CS

RSSWhat is it?‘Real Simple Syndication’ (aka ‘Rich Site Summary’)

What is it good for?– Pushing data to web clients– Originally for website and news updates– Now for sharing all types of information between

websites, and for podcasting

How Does RSS Function?

Broadcast text to subscribers using a simple and small XML-based language

<?xml version="1.0" encoding="ISO-8859-1" ?><rss version="2.0"><channel> <title>Dalhousie CS4173 Examples</title> <link>http://www.cs.dal.ca/~jamie/…/examples/</link> <description>real WWW code</description> <item> <title>CGI in general</title> <link>http://…/#CGI</link> <description>What CGI is & How to use it</description> </item> <item> <title>Self-generating CGI forms</title> <link>http://…</link> <description>Way kool demos</description> </item></channel></rss>

Adapted from

W3schools example Adapted from

W3schools example

Blog CharacteristicsStructure Chronological diary

+ comments+ trackbacks

Input Plain text (possibly with a little formatting) and links

Output HTML and links

Controlling Authority

Author(s) & commentators

Wiki what’s that?

http://en.wikipedia.org/wiki/Wiki

StudleyCaps or MixedCapitalization– Indicates WikiWord (significant term)– Each WikiWord has its own webpage

Wiki CharacteristicsStructure Terms and definitions

Input Plain text (possibly with a little formatting)

Output HTML and links

Controlling Authority

Author(s) & moderators can change

What About Sparrow Web?

http://www2.parc.com/istl/projects/sparrow/