How to insert multiple pieces of data through PHP MySQL

<?php$servername = "localhost";$username = "username";$password = "password";$dbname = "myDB"; 
// 创建链接$conn = new mysqli($servername, $username, $password, $dbname);// 检查链接if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);} 
 $sql = "INSERT INTO MyGuests (firstname, lastname, email)
VALUES (&#39;John&#39;, &#39;Doe&#39;, &#39;john@example.com&#39;);";$sql .= "INSERT INTO MyGuests (firstname, lastname, email)
VALUES (&#39;Mary&#39;, &#39;Moe&#39;, &#39;mary@example.com&#39;);";$sql .= "INSERT INTO MyGuests (firstname, lastname, email)
VALUES (&#39;Julie&#39;, &#39;Dooley&#39;, &#39;julie@example.com&#39;)"; 
if ($conn->multi_query($sql) === TRUE) {
    echo "新记录插入成功";} else {
    echo "Error: " . $sql . "<br>" . $conn->error;}
 $conn->close();?>

<?php$servername = "localhost";$username = "username";$password = "password";$dbname = "myDB"; 
// 创建链接$conn = mysqli_connect($servername, $username, $password, $dbname);// 检查链接if (!$conn) {
    die("连接失败: " . mysqli_connect_error());}
 $sql = "INSERT INTO MyGuests (firstname, lastname, email)
VALUES (&#39;John&#39;, &#39;Doe&#39;, &#39;john@example.com&#39;);";$sql .= "INSERT INTO MyGuests (firstname, lastname, email)
VALUES (&#39;Mary&#39;, &#39;Moe&#39;, &#39;mary@example.com&#39;);";$sql .= "INSERT INTO MyGuests (firstname, lastname, email)
VALUES (&#39;Julie&#39;, &#39;Dooley&#39;, &#39;julie@example.com&#39;)"; 
if (mysqli_multi_query($conn, $sql)) {
    echo "新记录插入成功";} else {
    echo "Error: " . $sql . "<br>" . mysqli_error($conn);}
 mysqli_close($conn);?>

<?php$servername = "localhost";$username = "username";$password = "password";$dbname = "myDBPDO"; 
try {
    $conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);    // set the PDO error mode to exception
    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); 
    // 开始事务
    $conn->beginTransaction();    // SQL 语句
    $conn->exec("INSERT INTO MyGuests (firstname, lastname, email) 
    VALUES (&#39;John&#39;, &#39;Doe&#39;, &#39;john@example.com&#39;)");    $conn->exec("INSERT INTO MyGuests (firstname, lastname, email) 
    VALUES (&#39;Mary&#39;, &#39;Moe&#39;, &#39;mary@example.com&#39;)");    $conn->exec("INSERT INTO MyGuests (firstname, lastname, email) 
    VALUES (&#39;Julie&#39;, &#39;Dooley&#39;, &#39;julie@example.com&#39;)"); 
    // 提交事务
    $conn->commit();    echo "新记录插入成功";}catch(PDOException $e){
    // 如果执行失败回滚
    $conn->rollback();    echo $sql . "<br>" . $e->getMessage();}
 $conn = null;?>

<?php$servername = "localhost";$username = "username";$password = "password";$dbname = "myDB"; 
// 创建连接$conn = new mysqli($servername, $username, $password, $dbname);// 检测连接if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);} else {
    $sql = "INSERT INTO MyGuests(firstname, lastname, email)  VALUES(?, ?, ?)"; 
    // 为 mysqli_stmt_prepare() 初始化 statement 对象
    $stmt = mysqli_stmt_init($conn); 
    //预处理语句
    if (mysqli_stmt_prepare($stmt, $sql)) {
        // 绑定参数
        mysqli_stmt_bind_param($stmt, &#39;sss&#39;, $firstname, $lastname, $email); 
        // 设置参数并执行
        $firstname = &#39;John&#39;;        $lastname = &#39;Doe&#39;;        $email = &#39;john@example.com&#39;;        mysqli_stmt_execute($stmt); 
        $firstname = &#39;Mary&#39;;        $lastname = &#39;Moe&#39;;        $email = &#39;mary@example.com&#39;;        mysqli_stmt_execute($stmt); 
        $firstname = &#39;Julie&#39;;        $lastname = &#39;Dooley&#39;;        $email = &#39;julie@example.com&#39;;        mysqli_stmt_execute($stmt);    }}?