PHP を使用して電子メールの検索と並べ替え機能を実装するにはどうすればよいですか?

<?php
// 连接数据库
$servername = "localhost";
$username = "root";
$password = "password";
$dbname = "mydatabase";

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

// 获取搜索关键词
$keyword = $_GET["keyword"];

// 查询数据库中的邮件信息
$sql = "SELECT * FROM emails WHERE title LIKE '%$keyword%' OR sender LIKE '%$keyword%' OR receiver LIKE '%$keyword%'";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
  // 输出搜索结果
  while($row = $result->fetch_assoc()) {
    echo "标题: " . $row["title"]. " - 发件人: " . $row["sender"]. " - 收件人: " . $row["receiver"]. "<br>";
  }
} else {
  echo "未找到相关邮件";
}

$conn->close();
?>

<?php
// 连接数据库
$servername = "localhost";
$username = "root";
$password = "password";
$dbname = "mydatabase";

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

// 获取排序属性
$sort = $_GET["sort"];

// 查询数据库中的邮件信息，并按照指定属性进行排序
$sql = "SELECT * FROM emails ORDER BY $sort";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
  // 输出排序结果
  while($row = $result->fetch_assoc()) {
    echo "标题: " . $row["title"]. " - 发件人: " . $row["sender"]. " - 收件人: " . $row["receiver"]. "<br>";
  }
} else {
  echo "未找到相关邮件";
}

$conn->close();
?>