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SQL Server DATEADD() Function

SQL Dates SQL Server Date Functions

Definition and Usage

The DATEADD() function is adds or subtracts a specified time interval from a date.

Syntax

DATEADD(datepart,number,date)

Where date is a valid date expression and number is the number of interval you want to add. The number can either be positive, for dates in the future, or negative, for dates in the past.

datepart can be one of the following:

datepartAbbreviation
yearyy, yyyy
quarterqq, q
monthmm, m
dayofyeardy, y
daydd, d
weekwk, ww
weekdaydw, w
hourhh
minutemi, n
secondss, s
millisecondms
microsecondmcs
nanosecondns

Example

Assume we have the following "Orders" table:

OrderId ProductName OrderDate
1 Jarlsberg Cheese 2008-11-11 13:23:44.657

Now we want to add 45 days to the "OrderDate", to find the payment date.

We use the following SELECT statement:

SELECT OrderId,DATEADD(day,45,OrderDate) AS OrderPayDate
FROM Orders

Result:

OrderIdOrderPayDate
12008-12-26 13:23:44.657

SQL Dates SQL Server Date Functions

From http://www.w3schools.com (Copyright Refsnes Data)