<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <title>Introduction</title> </head> <body><div class="manualnavbar" style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="book.pdo.html">PDO</a></div> <div class="next" style="text-align: right; float: right;"><a href="pdo.setup.html">Installing/Configuring</a></div> <div class="up"><a href="book.pdo.html">PDO</a></div> <div class="home"><a href="index.html">PHP Manual</a></div> </div><hr /><div id="intro.pdo" class="preface"> <h1 class="title">Introduction</h1> <p class="para"> The <em>PHP Data Objects</em> (<acronym>PDO</acronym>) extension defines a lightweight, consistent interface for accessing databases in PHP. Each database driver that implements the PDO interface can expose database-specific features as regular extension functions. Note that you cannot perform any database functions using the PDO extension by itself; you must use a <a href="pdo.drivers.html" class="link">database-specific PDO driver</a> to access a database server. </p> <p class="para"> PDO provides a <em class="emphasis">data-access</em> abstraction layer, which means that, regardless of which database you're using, you use the same functions to issue queries and fetch data. PDO does <em class="emphasis">not</em> provide a <em class="emphasis">database</em> abstraction; it doesn't rewrite SQL or emulate missing features. You should use a full-blown abstraction layer if you need that facility. </p> <p class="para"> PDO ships with PHP 5.1, and is available as a PECL extension for PHP 5.0; PDO requires the new OO features in the core of PHP 5, and so will not run with earlier versions of PHP. </p> </div><hr /><div class="manualnavbar" style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="book.pdo.html">PDO</a></div> <div class="next" style="text-align: right; float: right;"><a href="pdo.setup.html">Installing/Configuring</a></div> <div class="up"><a href="book.pdo.html">PDO</a></div> <div class="home"><a href="index.html">PHP Manual</a></div> </div></body></html>
