SQL 2016 new function DATEDIFF_BIG

   

    If you are dealing with dates in your databases DATEDIFF_BIG can be your best friend. You might already know about the function DATEDIFF which has the exact structure of DATEDIFF_BIG. Really the main difference between them is the DATEDIFF returns int and DATEDIFF_BIG returns bigint.
You can use both function in the select list, WHERE, HAVING, GROUP BY and ORDER BY clauses.

DATEDIFF_BIG (datepart, startdate, enddate)

This function returns bigint. startdate and enddate can be time,date,datetime, smalldatetime, datetime2 or datetimeoffset.

Available dataparts:

• 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)