<?php

$date1 = "2012-11-05 12:35:00";
$date2 = "2012-11-07 14:35:00"; 
echo strtotime($date2) ."\n";
$diff = strtotime($date2) - strtotime($date1);
echo $diff ."\n";
$diff_in_hrs = $diff/3600;
print_r($diff_in_hrs);










?>

1352298900
180000
50