test.php

<?php
$dsn = 'mysql:host=127.0.0.1:3306;dbname=mydb;charset=UTF8';
$username = 'root';
$password = '<dein passwort>';
$pdo = new PDO($dsn, $username, $password, array(PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION));

$stmt = $pdo->prepare('SELECT id, nickname, passwort, anrede, vorname, nachname, straße, plz, ort, telefon, email, geworben FROM nutzer ORDER BY :auswahl');
$stmt->execute(['auswahl' => $auswahl]);
$rows = $stmt->fetchAll(PDO::FETCH_ASSOC);
?>

<p>Es wurden <?= count($rows) ?> Datensätze gefunden</p>

<table border="2" rules="all">
	<thead>
		<tr>
			<th width='200'>ID:</th>
			<th>Nickname:</th>
			<th>Passwort:</th>
			<th>Anrede:</th>
			<th>Vorname:</th>
			<th>Nachname:</th>
			<th>Straße:</th>
			<th>PLZ:</th>
			<th>Ort:</th>
			<th>Telefon:</th>
			<th>E-Mail:</th>
			<th>geworben:</th>
			<th>&nbsp;</th>
		</tr>
	</thead>
	<tbody>
		<tr>
			<?php foreach($rows as $row): ?>
			<td><?= $row['nickname'] ?></td>
			<td><?= $row['passwort'] ?></td>
			<td><?= $row['anrede'] ?></td>
			<td><?= $row['vorname'] ?></td>
			<td><?= $row['nachname'] ?></td>
			<td><?= $row['straße'] ?></td>
			<td><?= $row['plz'] ?></td>
			<td><?= $row['ort'] ?></td>
			<td><?= $row['telefon'] ?></td>
			<td><?= $row['email'] ?></td>
			<td><?= $row['geworben'] ?></td>
			<td><a href="admin.php?seite=bearbeiten&id3=<?= $row['id'] ?>">Bearbeiten</a></td>
			<?php endforeach ?>
		</tr>
	</tbody>
</table>