如何使用php组合多个select语句以在表行中回显结果？

<?php
// 连接数据库
$servername = "数据库主机名";
$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("连接数据库失败: " . $conn->connect_error);
}

// 编写并执行SELECT语句
$sql1 = "SELECT * FROM 表名1 WHERE 条件";
$result1 = $conn->query($sql1);

$sql2 = "SELECT * FROM 表名2 WHERE 条件";
$result2 = $conn->query($sql2);

// 获取结果并回显
echo "<table>";
echo "<tr><th>列1</th><th>列2</th></tr>";

if ($result1->num_rows > 0 && $result2->num_rows > 0) {
    while ($row1 = $result1->fetch_assoc() && $row2 = $result2->fetch_assoc()) {
        echo "<tr>";
        echo "<td>" . $row1["列1"] . "</td>";
        echo "<td>" . $row2["列2"] . "</td>";
        echo "</tr>";
    }
} else {
    echo "<tr><td colspan='2'>没有找到匹配的结果。</td></tr>";
}

echo "</table>";

// 关闭数据库连接
$conn->close();
?>