Adding hours to a MySQL datetime using PHP

[skylabel]

I've got a datetime field called submitDate in a MySQL database.
I'm using PHP to read and display it as follows:

$submitDate = $row['submitDate'];
echo $submitDate;

It shows as:
2008-03-05 06:28:58

The format is cool, but now, I need to add 12 hours to that date and show it, so it should show
2008-03-05 18:28:58

How can I do this, using PHP?

Help much appreciated. Thanks.

[sagee]

if the time stamp is stored in the database as a PHP number you can just add the number of seconds you want & then show it any way you want using DATE function.

$x = time();

$y = $x + (2 * 24 * 60 * 60) ; // 2 days from now; 
//2 days , 24 hours , 60 minutes , 60 seconds

[Weedpacket]

Why not do it with MySQL?

SELECT DATE_ADD(submitDate, INTERVAL 12 HOUR) as submitLater

sagee wrote:

$y = $x + (2 * 24 * 60 * 60);

Warning: two days from now isn't necessarily the same thing as 48 hours from now.

[sagee]

Good point