I am trying to figure out how to code a stored procedure to return elapsed time values. The date portion is stored in the RecDateTime, the fields UpTime1 and DownTime1 have string values such as 15:30 and 15:45. The goal is turn return an additional column show the difference between UpTime1 and DownTime1, in this case it would be 15 minutes.

A hitch in the plan is that if there is not a value in UpTime1 and/or DownTime1 then I want to return a zero.

RecDateTime                        UpTime1         DownTime1
01/09/2009 12:13:00               15:30                15:45

RecDateTime is a datetime value
UpTime1 and DownTime1 are varchr(5)

Thanks for any help.

Kirk