SUBTRACT TIME TO DATE & TIME

Question

Hi.
I need SUBTRACT TIME TO DATE & Time.
Example:
Date = 08.05.2007
Time = 01:00:00
Time_subtract = 2:00:00
Return of FM:
Date = 07.05.2007
Time = 23:00:00
Do you know any FM?
Thanks!

Answer 1

Since the max time difference can be 24 hrs you can reduce that much amount of time from the initial date and then add the difference from the initial date.
Example : if time difference is to be calculated is 05:00:00 , since this is less than 24 , just add 24 -5 hrs = 19 hrs to the date ( subtract 1 from initial date ) using CONV_UTIL_ADD_DATE_AND_TIME.
If time to be added is greater than 24 hrs then subtract ( TIME/24 ) from original date and add the difference to date.
Example : 
Date = 08.05.2007
Time = 01:00:00
Time_subtract = 52:00:00
Subtract figure = 52/24 = 3 , 52 - 48 = 4.
Return of FM:
New date :
Date = 05.05.2007
Time = 01:00:00
Now add 4 to above date using FM to get result.