如何使用条带连接PHP创建新的外部帐户？

<?php
// 连接到MySQL数据库
$host = "localhost";
$username = "root";
$password = "password";
$database = "mydb";
$conn = mysqli_connect($host, $username, $password, $database);

// 检查连接是否成功
if (!$conn) {
    die("连接失败: " . mysqli_connect_error());
}

// 创建外部账户表
$sql = "CREATE TABLE external_accounts (
    id INT(6) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    username VARCHAR(30) NOT NULL,
    password VARCHAR(30) NOT NULL
)";
if (mysqli_query($conn, $sql)) {
    echo "外部账户表创建成功";
} else {
    echo "创建失败: " . mysqli_error($conn);
}

// 插入一条新的记录
$sql = "INSERT INTO external_accounts (username, password)
        VALUES ('john', 'password123')";
if (mysqli_query($conn, $sql)) {
    echo "新的外部账户创建成功";
} else {
    echo "创建失败: " . mysqli_error($conn);
}

// 查询外部账户表
$sql = "SELECT * FROM external_accounts WHERE username='john'";
$result = mysqli_query($conn, $sql);
if (mysqli_num_rows($result) > 0) {
    while ($row = mysqli_fetch_assoc($result)) {
        echo "账户ID: " . $row["id"] . "<br>";
        echo "用户名: " . $row["username"] . "<br>";
        echo "密码: " . $row["password"] . "<br>";
    }
} else {
    echo "没有找到账户";
}

// 关闭数据库连接
mysqli_close($conn);
?>