One method of doing this would be to cut out the stuff you want using substr() and store it in multiple variables or an array and then glue it back together in any form you wanted.
eg. For date
$mysql_date = "20000922";
$year = substr($mysql_date,0,4);
$month = substr($mysql_date,4,2);
$date = substr($mysql_date,6,2);
$my_date = $date."-".$month."-".$year;
Matt