php连接mysql

<?php
$servername = "127.0.0.1";
$username = "root";
$password = "root";

try {
    $pdo = new PDO("mysql:host=$servername;dbname=myDb", $username, $password);
    echo "连接成功"; 
}
catch(PDOException $e)
{
    echo $e->getMessage();
}

//$list = $pdo -> query("set names utf8");
$list = $pdo -> query("select * from myTable"); 
while($row = $list -> fetch()){ 
    print_r($row); 
} 

<?php
$servername = "127.0.0.1";
$username = "root";
$password = "root";
 
// 创建连接
$mysqli = new mysqli($servername, $username, $password);
 
// 检测连接
if ($mysqli->connect_error) {
    die("连接失败: " . $mysqli->connect_error);
} 
$mysqli->select_db(‘three‘);
//$mysqli->query(‘set names utf8‘);
$list=$mysqli->query(‘select * from jing_province‘);

while($row=$list->fetch_row()){
    print_r($row);
}