Most high-end Web sites have some kind of database behind them, helping to power the dynamic nature of the site. PHP has been capable of working with back-end databases for quite some time. Initially, it worked only with open source databases such as MySQL and mSQL, but now it can work with ODBC-compliant databases as well. This means that you can now Web-enable your Microsoft Access, Microsoft SQL Server, and Oracle databases using PHP.
This section examines how to pose queries to databases using PHP and how to dynamically build a Web page using the results from those queries. In particular, you will learn about the built-in functions that enable PHP to communicate with the following types of databases: