如何用php的select标签将数据发送到mysql表？

<form method="post" action="process.php">
  <select name="data">
    <option value="option1">Option 1</option>
    <option value="option2">Option 2</option>
    <option value="option3">Option 3</option>
  </select>
  <input type="submit" value="Submit">
</form>

<?php
// 连接到MySQL数据库
$servername = "数据库服务器地址";
$username = "数据库用户名";
$password = "数据库密码";
$dbname = "数据库名";

$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 处理表单提交的数据
$data = $_POST['data'];

// 将数据插入到MySQL表中
$sql = "INSERT INTO 表名 (列名) VALUES ('$data')";

if ($conn->query($sql) === TRUE) {
    echo "数据插入成功";
} else {
    echo "数据插入失败: " . $conn->error;
}

// 关闭数据库连接
$conn->close();
?>