PHP搭建自己的MVC框架7 模型层

<?php
namespace core\lib;
class model extends \pdo
{
public function __construct()
{
$dsn = 'mysql:host=localhost;dbname=test';
$username = 'root';
$passwd= 'root';
try {
parent::__construct($dsn, $username, $passwd);
} catch (\PDOException $e){
p($e->getMessage());
}
}

<?php
namespace app\ctrl;
class indexCtrl
{
public function index(){
$model = new \core\lib\model();

4000
$sql="select * from stu";
$model->query("set names utf8");
$res = $model->query($sql);
p($res->fetchAll());
}
}