如何通过PHP迭代MySQL的搜索结果？

<?php
// 连接数据库
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "database";
$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 执行查询
$sql = "SELECT * FROM your_table";
$result = $conn->query($sql);

// 迭代搜索结果
if ($result->num_rows > 0) {
    while ($row = $result->fetch_assoc()) {
        // 处理每一行数据
        echo "字段1: " . $row["column1"]. " - 字段2: " . $row["column2"]. "<br>";
    }
} else {
    echo "没有结果";
}

// 关闭连接
$conn->close();
?>

<?php
// 连接数据库
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "database";
try {
    $conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);
    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

    // 执行查询
    $sql = "SELECT * FROM your_table";
    $stmt = $conn->query($sql);

    // 迭代搜索结果
    while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
        // 处理每一行数据
        echo "字段1: " . $row["column1"]. " - 字段2: " . $row["column2"]. "<br>";
    }
} catch(PDOException $e) {
    echo "连接失败: " . $e->getMessage();
}

// 关闭连接
$conn = null;
?>