Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Three tier achitecture
Document related concepts
Transcript
Web sites based on data • What is it? – Large Web sites that support commercial use cannot be written by hand • What you’re going to learn – How a Web server and a database can be used to generate web pages from data. – Some systems that provide the necessary functionality – How a simple example looks in code. Web sites based on data Web Client / user 1. User requests a page Web Server 2. HTTP request sent 3. SQL query Runs program or script Response Web page on screen Database server data returned 4. Server executes query 5. Server script copies data in HTML format The “three tier architecture” Some technologies to use Web Client / user Web Server Database server Any Web browser Client languages: HTML, CSS, JavaScript Apache (most popular) Server language: MySQL PHP Query language: SQL Bundled in the package In practice: code <html> … <body> <h1>PHP and MySQL databases</h1> <?php $con = mysql_connect(“hostname","user","password"); mysql_select_db(“databasename", $con); ?> The lines in red are server commands, Embedded in the HTML code. http://www.boisvert.me.uk/run/elcid.html? file=users/charles/PHP_and_MySQL.xml (http://localhost/run/elcid.html?file=users/charles/PHP_and_MySQL.xml) Web sites based on data • What is it? – Large Web sites that support commercial use are written by programming the Web server to generate pages from database data • What you’ve learnt – The three-tier architecture supports dataoriented web sites – The open-source XAMPP package contains the necessary software – PHP server scripting is embedded within HTML code to program the system.
