MySQL Cookbook

Chapter 16. Introduction to MySQL on the Web

Introduction

The next few chapters discuss some of the ways that MySQL can help you build a better web site. In general, the principal benefit is that MySQL makes it easier to provide dynamic rather than static content. Static content exists as pages in the web server’s document tree that are served exactly as is. Visitors can access only the documents that you place in the tree, and changes occur only when you add, modify, or delete those documents. By contrast, dynamic content is created on demand. Rather than opening a file and serving its contents directly to the client, the web server executes a script that generates the page and sends the resulting output. As a simple example, a script can look up the current hit counter value in the database for a given web page, update the counter, and return the new value for display in the page. Each time the script executes, it produces a different value. More complex examples are scripts that show the names of people that have a birthday today, retrieve and display items in a product catalog, or provide information about the current status of the server. And that’s just for starters; web scripts have access to the power of the programming language in which they’re written, so the actions that they perform to generate pages can be quite extensive. For example, web scripts are important for form processing, and a single script may be responsible for generating a form and sending it to the user, ...