DATEADD
Returns a new datetime value based on adding an interval to the specified date.
Syntax
DATEADD ( datepart , number, date )
Arguments
datepart
Is the parameter that specifies on which part of the date to return a new value. The table lists the dateparts and abbreviations recognized by Microsoft® SQL Server™.
| 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 |
number
Is the value used to increment datepart. If you specify a value that is not an integer, the fractional part of the value is discarded. For example, if you specify day for datepart and1.75 for number, date is incremented by 1.
date
Is an expression that returns a datetime or smalldatetime value, or a character string in a date format. For more information about specifying dates, see datetime and smalldatetime.
If you specify only the last two digits of the year, values less than or equal to the last two digits of the value of the two digit year cutoff configuration option are in the same century as the cutoff year. Values greater than the last two digits of the value of this option are in the century that precedes the cutoff year. For example, if two digit year cutoff is 2049 (default), 49 is interpreted as 2049 and 2050 is interpreted as 1950. To avoid ambiguity, use four-digit years.
Return Types
Returns datetime, but smalldatetime if the date argument is smalldatetime.
Examples
This example prints a listing of a time frame for titles in the pubs database. This time frame represents the existing publication date plus 21 days.
USE pubs
GO
SELECT DATEADD(day, 21, pubdate) AS timeframe
FROM titles
GO
Here is the result set:
timeframe
---------------------------
Jul 3 1991 12:00AM
Jun 30 1991 12:00AM
Jul 21 1991 12:00AM
Jul 13 1991 12:00AM
Jun 30 1991 12:00AM
Jul 9 1991 12:00AM
Mar 14 1997 5:09PM
Jul 21 1991 12:00AM
Jul 3 1994 12:00AM
Mar 14 1997 5:09PM
Nov 11 1991 12:00AM
Jul 6 1991 12:00AM
Oct 26 1991 12:00AM
Jul 3 1991 12:00AM
Jul 3 1991 12:00AM
Nov 11 1991 12:00AM
Jul 3 1991 12:00AM
Jul 3 1991 12:00AM
(18 row(s) affected)