不确定如何在mysql中使用php变量

<?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语句
$sql = "SELECT * FROM your_table WHERE column_name = ?";

// 绑定变量
$stmt = $conn->prepare($sql);
$stmt->bind_param("s", $variable);

// 设置变量的值
$variable = "your_value";

// 执行SQL语句
$stmt->execute();

// 获取结果
$result = $stmt->get_result();

// 处理结果
while ($row = $result->fetch_assoc()) {
    // 处理每一行数据
    echo $row["column_name"];
}

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