<?php
class DB extends PDO {
	public function __construct($host, $username, $password, $database, $port = '3306', $charset = 'UTF8') {
		$driverOptions = array (
				PDO::ATTR_PERSISTENT => true,
				PDO::ATTR_CASE => PDO::CASE_LOWER,
				PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8",
				PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION 
		);
		if ($host) {
			$dsn = 'mysql:host=' . $host . ';dbname=' . $database . ';charset=' . $charset . ';port=' . $port . '';
		} else {
			$dsn = 'odbc:driver={microsoft access driver (*.mdb)};dbq=' . realpath ( $database ) . ';PWD=' . $password;
		}
		try {
			return parent::__construct ( $dsn, $username, $password, $driverOptions );
		} catch ( PDOException $e ) {
			echo $e->getMessage ();
		}
	}
	public function fetchAll($query, $parameters = array(), $type = PDO::FETCH_ASSOC) {
		$rs = $this->prepareAndExecute ( $query, $parameters );
		
		$rows = $rs->fetchAll ( $type );
		$rs->closeCursor ();
		
		unset ( $rs );
		return $rows;
	}
	public function fetchRow($query, $parameters = array(), $type = PDO::FETCH_ASSOC) {
		$rs = $this->prepareAndExecute ( $query, $parameters );
		
		$row = $rs->fetch ( $type );
		$rs->closeCursor ();
		
		unset ( $rs );
		return $row;
	}
	public function fetchValue($query, $parameters = array()) {
		return $this->fetchRowValue ( $query, $parameters, 0 );
	}
	public function fetchRowValue($query, $parameters = array(), $column = 0) {
		$rs = $this->prepareAndExecute ( $query, $parameters );
		
		$row = $rs->fetchColumn ( $column );
		$rs->closeCursor ();
		
		unset ( $rs );
		return $row;
	}
	public function update($query, $parameters) {
		$rs = $this->prepareAndExecute ( $query, $parameters );
		return $rs->rowCount ();
	}
	public function insert($query, $parameters = array()) {
		$rs = $this->prepareAndExecute ( $query, $parameters );
		return $this->lastInsertId ();
	}
	public function prepareAndExecute($query, $parameters = array()) {
		$rs = $this->prepare ( $query );
		$rs->execute ( $parameters );
		return $rs;
	}
}

$Mysql = new DB ( 'localhost', 'root', '123456', 'wordpress' );
$Access = new DB ( false, false, '1234567890', 'content.mdb' );

var_dump ( $Mysql->getAttribute ( PDO::ATTR_DRIVER_NAME ) );
echo '<hr />';//py by http://my.oschina.net/cart/
var_dump ( $Access->getAttribute ( PDO::ATTR_DRIVER_NAME ) );