How to use the Datediff function?

How to use the datediff function in Crystal reports? i am having a problem on what value shall i put in the intervaltype. the datediff fuction has intervaltype in it with startdatetime and enddatetime. can you teach me how to?

The Interval type argument specifies the unit of Time intervals you want to return. For example the number of days between two dates, the number of hours etc..

This returns the number of seconds that have elapsed since midnight.

DateDiff("s",CurrentDate,CurrentDateTime)

From the Help file.

intervalType is a String expression that is the interval of time you use to calculate the difference between startDateTime and endDateTime. Possible values can be:

Code:

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Interval type Description 
yyyy            Year
q                  Quarter
m                Month
y                  Day of year
d                  Day (both "y" and "d" find the difference in days)
w                Number of weeks between startDateTime and endDateTime
ww              Number of firstDayOfWeek's between startDateTime and endDateTime
h                Hour
n                Minute
s                Second

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