MySQL PDO 연결 및 작동

<p>//实例化PDO类 连接数据库  参数是 mysql:host=localhost;dbname=lamp 用户名  密码
$pdo = new PDO('mysql:host=localhost;dbname=lamp', 'root', '');</p><p>//查询语句
</p><p>$sql = "select * from lamp_login";
$stmt = $pdo->query($sql);</p><p>//增 删  改</p><p>$pdo->exec($sql);
</p><p>PDO::FETCH_OBJ相当于mysql_fetch_object</p><pre dir="ltr">object(<em>stdClass</em>)[<em>3</em>]
  <em>public</em> 'id' <span>=></span><small>string</small><span>'1'</span><em>(length=1)
  public</em> 'username' <span>=></span><small>string</small><span>'user1'</span><em>(length=5)
  public</em> 'password' <span>=></span><small>string</small><span>'123'</span><em>(length=3)</em>

array<em>(size=6)</em>
  'id' <span>=></span><small>string</small><span>'2'</span><em>(length=1)</em>
  0 <span>=></span><small>string</small><span>'2'</span><em>(length=1)</em>
  'username' <span>=></span><small>string</small><span>'user2'</span><em>(length=5)</em>
  1 <span>=></span><small>string</small><span>'user2'</span><em>(length=5)</em>
  'password' <span>=></span><small>string</small><span>'234'</span><em>(length=3)</em>
  2 <span>=></span><small>string</small><span>'234'</span><em>(length=3)</em>

array<em>(size=3)</em>
  0 <span>=></span><small>string</small><span>'3'</span><em>(length=1)</em>
  1 <span>=></span><small>string</small><span>'user3'</span><em>(length=5)</em>
  2 <span>=></span><small>string</small><span>'345'</span><em>(length=3)</em>

array<em>(size=3)</em>
  'id' <span>=></span><small>string</small><span>'4'</span><em>(length=1)</em>
  'username' <span>=></span><small>string</small><span>'zhouyao'</span><em>(length=7)</em>
  'password' <span>=></span><small>string</small><span>'123456'</span><em>(length=6)</em>