[PHP] ORDER BY mySQL problem

OK, i have made the user name, scores and time to be recorded into a MySQL table and i have managed to have this data sent back to my swf - but it is showing the lowest score at the top - how to switch it and make the highest take the number 1 postition?

here’s my code:
$sql = “SELECT * FROM $table_name ORDER BY total”;
$result=mysql_query($sql, $db);

this works - but i tried adding DESC
$sql = “SELECT * FROM $table_name ORDER BY total DESC”;
$result=mysql_query($sql, $db);

and this makes it not work!
any suggestions?