час между двумя Datatime SQL

Declare @InTime datetime='2017-11-27 10:00:00',
 @OutTime datetime='2017-11-27 11:15:00'

 SELECT CONVERT(varchar(5),DATEADD(minute,DATEDIFF(minute,@InTime,@OutTime),0), 114)
 -----------
 Result
 01:15
Angry Albatross