php-guestbook/form.php

<?php

include_once('persistence.php');
$db = createDB();

function newMessagePOST($db) {
    if(isset($_POST['message']) && $_POST['message']) {
        if(isset($_POST['name']) && $_POST['name']) {
            $name = $_POST['name'];
            $message = $_POST['message'];
            storeMessage($db, $message);
        }
        else {
            $message = $_POST['message'];
            storeMessage($db, $message);
        }
    }
}
newMessagePOST($db);
header("Location: /index.php");
exit;