How to calculate time difference past midnight!

[SimonBurrell]

I hope this helps someone when trying to work out how to calculate the time difference when the endtime is the next day.

I finally worked it out (thanks to the legendary Dr Bull).

/* This returns an output in minutes. If whole hours is the result you want - change the 720 (minutes) to 12 (hours) and change the datediff datepart to hh (hours)*/

SELECT TimeDiff =
  	CASE
	WHEN  EndTime < Starttime  THEN (720 -((datediff(mi,EndTime,StartTime )) - 720)) 
	WHEN EndTime > Starttime THEN(datediff(mi, StartTime, EndTime))
          END
FROM YourTable

Regards

Simon