AS others have indicated, the "datepart" is the desginator for the part of the date on which to calculate the date difference. SQL Books Online Help will give you all these answers. Just type in "DATEDIFF". The dateparts listed are:

datepart  Abbreviations  
year  yy, yyyy 
 
quarter  qq, q 
 
month  mm, m 
 
dayofyear  dy, y 
 
day  dd, d 
 
week  wk, ww 
 
hour  hh 
 
minute  mi, n 
 
second ss, s 
 
millisecond  ms 
 
microsecond  mcs 
 
nanosecond  ns

Bill

>>Hi Kevin,
>>
>>One method would be to use the T-SQL DATEDIFF ( datepart , startdate , enddate ) function.
>>
>>Bill
>>
>>>How do I calculate the number of days between two dates in SQL?
>>>
>>>

>>>SELECT APM_InvoiceDate - APM_DiscDate AS [VR-DSC-DAYS]
>>>	FROM iERP72_Test.dbo.APM
>>>

>>>
>>>This returns a datetime
>
>Specifying what for datepart?