Essaye ça...
PHP Code:
require("confmysql.php");
$mysql_link = mysql_connect($sql_serveur, $sql_user, $sql_password);
$requete = "SELECT COUNT(id) AS total FROM " . $sql_table . " WHERE etat = occaz";
$result = mysql_query($requete);
$occaz = mysql_fetch_array($result);
mysql_free_result($result);
mysql_close($mysql_link);
echo $occaz['total']" . voiture(s)";
Sinon, il faut utiliser mysql_query plutôt que mysql_db_query...