用PHP合并和显示不同表格中的数据

<?php
// 连接数据库
$servername = "localhost";
$username = "your_username";
$password = "your_password";
$dbname = "your_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);
}

// 查询数据
$sql = "SELECT * FROM table1";
$result1 = $conn->query($sql);

$sql = "SELECT * FROM table2";
$result2 = $conn->query($sql);

// 合并数据
$data = array();

if ($result1->num_rows > 0) {
    while ($row = $result1->fetch_assoc()) {
        $data[] = $row;
    }
}

if ($result2->num_rows > 0) {
    while ($row = $result2->fetch_assoc()) {
        $data[] = $row;
    }
}

// 显示数据
if (!empty($data)) {
    echo "<table>";
    echo "<tr><th>列1</th><th>列2</th><th>列3</th></tr>";

    foreach ($data as $row) {
        echo "<tr>";
        echo "<td>" . $row['column1'] . "</td>";
        echo "<td>" . $row['column2'] . "</td>";
        echo "<td>" . $row['column3'] . "</td>";
        echo "</tr>";
    }

    echo "</table>";
} else {
    echo "没有数据可显示。";
}

// 关闭数据库连接
$conn->close();
?>