$updateData = [$title, $url, $content, $short_content, $category_id, $edit['id']];
$updateFields = "title=?, url=?, content=?, short_content=?, category_id=?";

if($_POST['image'] != null){
    $updateData[] = $e;
    $updateFields .= ", image=?";
}

$sorgu = $pdo->prepare("UPDATE posts SET $updateFields WHERE id = ?");
$updateData[] = $edit['id'];
$sorgu->execute($updateData);