Datadriven web sites

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Data-driven web sites
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Lesson Plan

• The reason for database driven websites
• Common set ups
• Examples of database driven websites

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Why Database?

• HTML is the language of the world wide web.
• Traditionally designers would code each page by
  hand using HTML
• As web pages got more complex WYSIWYG editors
  like Dreamweaver became popular
• The pages are still created individually using
  this approach.

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Problems with this Approach

• Think about Amazon
• Could they create a separate page for each book?
• Now think of Ebay
• Does someone create a page every time someone
  auctions a new item
• Now think of google
• It would be impossible to create a new page for
  every possible search combination

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The Solution - Databases

• Very common to use a database combined with a
  website
• Information is taken from the database and
  displayed in the website
• The content of the database can be displayed in
  many different ways
• Many sites give users power to add to database
  -Forums, Ebay, Facebook

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Strengths of databases

• Databases offer efficient storage and retrieval
  of information
• Easy and quick to search through large quantities
  of info to find specific records
• Find all the customers who bought both computer
  and philosophy books
• Let the database do the work
• Databases sort data more efficiently than internt
  programming langauges

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What is a Database

• Tempting to think of a database as simply tables
  of information
• Many people find it easier to use Excel to hold
  tabular data
• They can still sort and filter information
• WRONG!
• Spreadsheets ares designed for calculations
• Databases are designed to store data

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Database features

• Excellent for searching for data contained in the
  database
• We can be very specific about what we search for
• The database can automatically sort search
  results
• It can calculate totals and averages of the data
  retrieved
• They save us from a lot of web programming

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Common Setups
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Microsoft Solutions

• Active Server Pages (ASP)?
• Now being replaced by ASP.NET
• Traditional ASP uses VBScript
• The .Net framework uses the VB or C languages
• ASP Pages can store and retrieve data using
  ActiveX Data Objects (ADO)?

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Microsoft Databases

• MS SQL Server is the Microsoft business Database
  Management System (DBMS)?
• It is not cheap but is a user-friendly DBMS
• SQL Server is often used with ASP and ASP.NET
• Home users and beginners sometimes use Access as
  cheap alternative

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Open Source Solutions

• Theses products are free to use under licence
• LAMP
• Linux operating system
• Apache web server
• MySQL database
• PHP/Perl/Python programming language
• Ruby on Rails
• The new kid on the block

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Other Solutions

• Sun's alternative to ASP is called JSP
• Java Server Pages use Java as the programming
  language
• Aimed at the business market
• Most DBMS's can be linked to most programming
  languages
• E.G. Oracle, DB2, Postgres

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Examples of Database Driven Websites
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Form Filling

• The user enters information in a web form that
  interacts with the database
• Can be used to make decisions
• e.g. Insurance Quotes. The DBMS searches for the
  relevant info and displays it on the web page
• Sometimes user input is stored and displayed
• Web forums and online petitions are examples of
  this

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eCommerce

• The catalogue of items for sale is stored in the
  database
• Product info is retrieved from DB and displayed
  on the website
• Users can fill in a web form selecting the
  product they want and entering their payment
  details
• This information goes into DB ready for the
  companies sales team.

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Tracking Behaviour

• Many sites track your behaviour without overtly
  using form filling or accounts
• Flickr tracks photos which are popular or ignored
  to develop interestingness rating
• Amazon matches your browsing history with similar
  users to make recommendations

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Content Management Systems (CMS)?

• Web site is designed so non-developers can add
  and update content on their website
• The administrator fills in a web form that
  populates the database
• When a user visits, content is pulled from DB and
  placed into templates
• Wikis and Blogs both work in very similar ways

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Web 2.0

• Buzzword - often used for sites where the users
  create the content
• Examples include Ebay, Facebook, Fickr, YouTube
• The user fills in a web form
• This information get stored in DB
• This information gets displayed in the website

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Search Engines

• Google, Yahoo, Ask etc
• Very technical and specialised database
  application
• Search Engines collect information about web
  sites and store them in a DB
• Use complex algorithms to get a seach engine
  ranking