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10/04/2012

DATENAME (Transact-SQL)

Returns a character string that represents the specified datepart of the specified date

For an overview of all Transact-SQL date and time data types and functions, see Date and Time Functions (Transact-SQL). For information and examples that are common to date and time data types and functions, see Using Date and Time Data.

Topic link icon Transact-SQL Syntax Conventions

Syntax

DATENAME (datepart ,date )

Arguments

datepart
Is the part of the date to return. 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
weekday	dw
hour	hh
minute	mi, n
second	ss, s
millisecond	ms
microsecond	mcs
nanosecond	ns
TZoffset	tz

date
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.

To avoid ambiguity, use four-digit years. For information about two-digit years, see two digit year cutoff Option.

Return Type

nvarchar

Return Value

Each datepart and its abbreviations return the same value.

The return value depends on the language environment set by using SET LANGUAGE and by the default language of the login. The return value is dependant on SET DATEFORMAT if date is a string literal of some formats. SET DATEFORMAT does not affect the return value when the date is a column expression of a date or time data type.

For versions of SQL Server later than SQL Server 2000, when the date parameter has a date data type argument, the return value depends on the setting specified by using SET DATEFIRST.

TZoffset datepart Argument

If datepart argument is TZoffset (tz) and the date argument has no time zone offset, 0 is returned.

smalldatetime date Argument

When date is smalldatetime, seconds are returned as 00.

Default Returned for a datepart That Is Not in the date Argument

If the data type of the date argument does not have the specified datepart, the default for that datepart will be returned.

For example, the default year-month-day for any date data type is 1900-01-01. The following statement has date part arguments for datepart, a time argument for date, and returns 1900, January, 1, 1, Monday.

SELECT DATENAME(year, '12:10:30.123')
    ,DATENAME(month, '12:10:30.123')
    ,DATENAME(day, '12:10:30.123')
    ,DATENAME(dayofyear, '12:10:30.123')
    ,DATENAME(weekday, '12:10:30.123');

The default hour-minute-second for the time data type is 00:00:00. The following statement has time part arguments for datepart, a date argument for date, and returns 0, 0, 0.

SELECT DATENAME(hour, '2007-06-01')
    ,DATENAME(minute, '2007-06-01')
    ,DATENAME(second, '2007-06-01');

Remarks

DATENAME can be used in the select list, WHERE, HAVING, GROUP BY, and ORDER BY clauses. In SQL Server 2008 R2, DATENAME implicitly casts string literals as a datetime2 type. This means that DATEDIFF no longer supports the format YDM when the date is passed as a string. You must explicitly cast the string to a datetime or smalldatetime type to use the YDM format.

Examples

The following example returns the date parts for the specified date.

SELECT DATENAME(datepart,'2007-10-30 12:15:32.1234567 +05:10')

Here is the result set.

datepart	Return value
year, yyyy, yy	2007
quarter, qq, q	4
month, mm, m	October
dayofyear, dy, y	303
day, dd, d	30
week, wk, ww	44
weekday, dw	Tuesday
hour, hh	12
minute, n	15
second, ss, s	32
millisecond, ms	123
microsecond, mcs	123456
nanosecond, ns	123456700
TZoffset, tz	310

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