如何在PHP中使用while循环列出具有相同ID的数据？[关闭]

按排序结果

series_id

$stmt = $pdo->prepare("SELECt series_id, product_name FROM yourTable ORDER BY series_id");$stmt->execute();

然后在显示结果时，显示Series标头，并

<ul>

$last_series = null;echo "<ul>n";while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {    if ($row['series_id'] != $last_series) {        if ($last_series) { echo "</ul></li>n";        }        echo "<li>" . $row['series_id'] . " Series Productn";        echo "<ul>n";        $last_series = $row['series_id'];    }    echo "<li>" . $row['product_name'] . "</li>n";}if ($last_series) {    echo "</li>n";}echo "</ul>n";