php pdo与mysqli连接mysql用法对比

// pdo
$pdo = new pdo("mysql:host=localhost;dbname=database", 'username', 'password');
// mysqli, 面向过程方式
$mysqli = mysqli_connect('localhost','username','password','database');
// mysqli, 面向对象
$mysqli = new mysqli('localhost','username','password','database');

3、数据库支持 pdo支持多种数据库，但mysqli只支持mysql

4、命名参数name parameter pdo方式：

$params = array(':username' => 'test', ':email' => $mail, ':last_login' => time() - 3600);
$pdo->prepare('
select * from users
where username = :username
and email = :email
and last_login > :last_login');

而mysqli则麻烦点，不支持这样，只能：

$query = $mysqli->prepare('
select * from users
where username = ?
and email = ?
and last_login > ?');
$query->bind_param('sss', 'test', $mail, time() - 3600);
$query->execute();

这样的话，一个个对问号的顺序，也比较麻烦，不大方便。

5、orm映射的支持 比如有个类user，例如：

class User
{
    public $id;
    public $first_name;
    public $last_name;
    public function info()
    {
        return '#' . $this->id . ': ' . $this->first_name . ' ' . $this->last_name;
    }
}
$query = "SELECT id, first_name, last_name FROM users";
// PDO
$result = $pdo->query($query);
$result->setFetchMode(PDO::FETCH_CLASS, 'User');
while ($user = $result->fetch())
{
    echo $user->info() . "\n";
}

mysqli用面向过程的方式：

if ($result = mysqli_query($mysqli, $query)) {
　　while ($user = mysqli_fetch_object($result, 'User')) {
　　echo $user->info()."\n";
　　}
}

6、防止sql注入（php防止sql注入的方法解析）： pdo 手工设置

$username = pdo::quote($_get['username']);
$pdo->query("select * from users where username = $username");

使用mysqli：

$username = mysqli_real_escape_string($_get['username']);
$mysqli->query("select * from users where username = '$username'");

7、preparestament pdo方式：

$pdo->prepare('select * from users where username = :username');
$pdo->execute(array(':username' => $_get['username']));

mysqli方式：

$query = $mysqli->prepare('select * from users where username = ?');
$query->bind_param('s', $_get['username']);
$query->execute();