- date_create: documentation ( source)
- date_interval_create_from_date_string: documentation ( source)
- date_format: documentation ( source)
- date_sub: documentation ( source)
<?php
$date=date_create("2013-03-15 20:21:24");
date_sub($date,date_interval_create_from_date_string("10 days"));
echo date_format($date,"Y-m-d");
?>