대규모 데이터 세트에 대해 PHP 및 MySQL에서 페이지 매김을 구현하는 방법은 무엇입니까?

SELECT * FROM 'redirect'
WHERE 'user_id'= \''.$_SESSION['user_id'].' \' 
ORDER BY 'timestamp'

<code class="php">$perPage = 10;
$page = (isset($_GET['page'])) ? (int)$_GET['page'] : 1;
$startAt = $perPage * ($page - 1);</code>

<code class="php">$query = "SELECT COUNT(*) as total FROM redirect
WHERE user_id = '".$_SESSION['user_id']."'";
$r = mysql_fetch_assoc(mysql_query($query));
$totalPages = ceil($r['total'] / $perPage);</code>

<code class="php">$links = "";
for ($i = 1; $i <= $totalPages; $i++) {
  $links .= ($i != $page ) 
            ? "<a href='index.php?page=$i'>Page $i</a> "
            : "$page ";
}</code>

<code class="php">$query = "SELECT * FROM 'redirect'
WHERE 'user_id'= \''.$_SESSION['user_id'].' \' 
ORDER BY 'timestamp' LIMIT $startAt, $perPage";
$result = mysql_query($query);</code>