如何回显同一个表中2列的结果- PHP

<?php
// 连接数据库
$servername = "数据库服务器名称";
$username = "数据库用户名";
$password = "数据库密码";
$dbname = "数据库名称";

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

// 查询表中两列的结果
$sql = "SELECT column1, column2 FROM your_table_name";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
    // 输出数据
    while($row = $result->fetch_assoc()) {
        echo "列1: " . $row["column1"]. " - 列2: " . $row["column2"]. "<br>";
    }
} else {
    echo "0 结果";
}

// 关闭数据库连接
$conn->close();
?>