$db = mysql_connect('YOUR_DB_ADDRESS','YOUR_DB_USER','YOUR_DB_PASS') or die("Database error");
mysql_select_db('YOUR_DB', $db);
$query = "INSERT INTO gastbuch (absender, betreff, message, datum) VALUES ('Sunnyboy', 'Test', 'Meine Nachricht', now())"
$result = mysql_query($query) or...