如何为我的数据库列'photo‘赋值$filenameTosTor？

<?php
// 连接到MySQL数据库
$servername = "localhost";
$username = "your_username";
$password = "your_password";
$dbname = "your_database";

$conn = new mysqli($servername, $username, $password, $dbname);

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

// 准备SQL查询
$sql = "UPDATE your_table SET photo = ?";

// 创建一个预处理语句
$stmt = $conn->prepare($sql);

// 绑定参数
$stmt->bind_param("s", $filenameTosTor);

// 执行查询
$stmt->execute();

// 关闭连接
$stmt->close();
$conn->close();
?>