使用mysql和php从两个表中的mysql数据库得到的基于优先级的结果

SELECT * FROM table1
UNION
SELECT * FROM table2
ORDER BY priority_column;

<?php
// 连接到MySQL数据库
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "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);
}

// 执行查询
$sql = "SELECT * FROM table1
        UNION
        SELECT * FROM table2
        ORDER BY priority_column";
$result = $conn->query($sql);

// 检查查询结果
if ($result->num_rows > 0) {
    // 输出数据
    while($row = $result->fetch_assoc()) {
        echo "优先级: " . $row["priority_column"]. " - 数据: " . $row["data_column"]. "<br>";
    }
} else {
    echo "没有结果";
}

// 关闭连接
$conn->close();
?>