How do you add minutes to a DATETIME field?
08/12/2013 11:00:00 PM + 120 minutes
You can just use the add (+) symbol but the value is added in seconds.
120 minutes is 7200 seconds.
NewDateTime = OldDateTime + 7200
Or, for coding clarity as pointed out by Tamar:
NewDateTime = OldDateTime + (120 * 60)