Sql server® 2012 t-sql fundamentals

part, n, dt_val)

Valid values for the part input include year, quarter, month, dayofyear, day, week, weekday, hour, 

minute, second, millisecond, microsecond, and nanosecond. You can also specify the part in abbrevi-

ated form, such as yy instead of year. Refer to SQL Server Books Online for details.

The return type for a date and time input is the same type as the input’s type. If this function is 

given a string literal as input, the output is DATETIME.

For example, the following code adds one year to February 12, 2009.

SELECT DATEADD(year, 1, '20090212');

This code returns the following output.

----------------------- 

2010-02-12 00:00:00.000

The 

DATEDIFF

 Function

The DATEDIFF function returns the difference between two date and time values in terms of a speci-

fied date part.

Syntax

DATEDIFF(