DATEDIFF
Returns the count (signed integer) of the specified datepart boundaries crossed between the specified startdate and enddate.
Syntax
DATEDIFF ( datepart , startdate , enddate )
Arguments
datepart
Is the part of startdate and enddate that specifies the type of boundary crossed. The following table lists all valid datepart arguments. User-defined variable equivalents are not valid.
| 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 |
startdate
Is an expression that can be resolved to a time, date, smalldatetime, datetime, datetime2, or datetimeoffset value.
date can be an expression, column expression, user-defined variable, or string literal. startdate is subtracted from enddate.
To avoid ambiguity, use four-digit years.
enddate
See startdate.
Return types
int
Example
SELECT DATEDIFF(hour, 0, '2007-05-10 12:10:09.331');