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date (Transact-SQL)

Defines a date.

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

date Description

Property

Value

Syntax

date

Usage

DECLARE @MyDate date

CREATE TABLE Table1 ( Column1 date )

Default string literal format

(used for down-level client)

YYYY-MM-DD

For more information, see the "Backward Compatibility for Down-level Clients" section of Using Date and Time Data.

Range

0001-01-01 through 9999-12-31

January 1, 1 A.D. through December 31, 9999 A.D.

Element ranges

YYYY is four digits from 0001 to 9999 that represent a year.

MM is two digits from 01 to 12 that represent a month in the specified year.

DD is two digits from 01 to 31, depending on the month, that represent a day of the specified month.

Character length

10 positions

Precision, scale

10, 0

Storage size

3 bytes, fixed

Storage structure

1, 3-byte integer stores date.

Accuracy

One day

Default value

1900-01-01

This value is used for the appended date part for implicit conversion from time to datetime2 or datetimeoffset.

Calendar

Gregorian

User-defined fractional second precision

No

Time zone offset aware and preservation

No

Daylight saving aware

No

Supported String Literal Formats for date

The following tables show the valid string literal formats for the date data type.

Numeric

Description

mdy                         

[m]m/dd/[yy]yy       

[m]m-dd-[yy]yy       

[m]m.dd.[yy]yy       

myd                         

mm/[yy]yy/dd       

mm-[yy]yy/dd       

[m]m.[yy]yy.dd       

dmy                         

dd/[m]m/[yy]yy       

dd-[m]m-[yy]yy       

dd.[m]m.[yy]yy       

dym                         

dd/[yy]yy/[m]m       

dd-[yy]yy-[m]m       

dd.[yy]yy.[m]m       

ymd                         

[yy]yy/[m]m/dd       

[yy]yy-[m]m-dd       

[yy]yy-[m]m-dd       

[m]m, dd, and [yy]yy represents month, day, and year in a string with slash marks (/), hyphens (-), or periods (.) as separators.

Only four- or two-digit years are supported. Use four-digit years whenever possible. To specify an integer from 0001 to 9999 that represents the cutoff year for interpreting two-digit years as four-digit years, use the two digit year cutoff Option.

A two-digit year that is less than or equal to the last two digits of the cutoff year is in the same century as the cutoff year. A two-digit year that is greater than the last two digits of the cutoff year is in the century that comes before the cutoff year. For example, if the two-digit year cutoff is the default 2049, the two-digit year 49 is interpreted as 2049 and the two-digit year 50 is interpreted as 1950.

The default date format is determined by the current language setting. You can change the date format by using the SET LANGUAGE and SET DATEFORMAT statements.

The ydm format is not supported for date.

Alphabetical

Description

mon [dd][,] yyyy      

mon dd[,] [yy]yy      

mon yyyy [dd]          

[dd] mon[,] yyyy      

dd mon[,][yy]yy       

dd [yy]yy mon         

[dd] yyyy mon         

yyyy mon [dd]         

yyyy [dd] mon         

mon represents the full month name or the month abbreviation given in the current language. Commas are optional and capitalization is ignored.

To avoid ambiguity, use four-digit years.

If the day is missing, the first day of the month is supplied.

ISO 8601

Descripton

YYYY-MM-DD            

YYYYMMDD               

Same as the SQL standard. This is the only format that is defined as an international standard.

Unseparated

Description

[yy]yymmdd            

yyyy[mm][dd]          

The date data can be specified with four, six, or eight digits. A six- or eight-digit string is always interpreted as ymd. The month and day must always be two digits. A four-digit string is interpreted as year.

ODBC

Description

{ d 'yyyy-mm-dd' }   

ODBC API specific.

Functions in SQL Server 2008 as in SQL Server 2005.

W3C XML format

Description

yyyy-mm-ddTZD      

Specifically supported for XML/SOAP usage.

TZD is the time zone designator (Z or +hh:mm or -hh:mm):

  • hh:mm represents the time zone offset. hh is two digits, ranging from 0 to 14, that represent the number of hours in the time zone offset.

  • MM is two digits, ranging from 0 to 59, that represent the number of additional minutes in the time zone offset.

  • + (plus) or – (minus) the mandatory sign of the time zone offset. This indicates that the time zone offset is added or subtracted from the Coordinated Universal Times (UTC) time to obtain the local time. The valid range of time zone offset is from -14:00 to +14:00.

ANSI and ISO 8601 Compliance

date complies with the ANSI SQL standard definition for the Gregorian calendar: "NOTE 85 - Datetime data types will allow dates in the Gregorian format to be stored in the date range 0001–01–01 CE through 9999–12–31 CE."

The default string literal format, which is used for down-level clients, complies with the SQL standard form which is defined as YYYY-MM-DD. This format is the same as the ISO 8601 definition for DATE.

Examples

The following example compares the results of casting a string to each date and time data type.

SELECT 
     CAST('2007-05-08 12:35:29. 1234567 +12:15' AS time(7)) AS 'time' 
    ,CAST('2007-05-08 12:35:29. 1234567 +12:15' AS date) AS 'date' 
    ,CAST('2007-05-08 12:35:29.123' AS smalldatetime) AS 
        'smalldatetime' 
    ,CAST('2007-05-08 12:35:29.123' AS datetime) AS 'datetime' 
    ,CAST('2007-05-08 12:35:29. 1234567 +12:15' AS datetime2(7)) AS 
        'datetime2'
    ,CAST('2007-05-08 12:35:29.1234567 +12:15' AS datetimeoffset(7)) AS 
        'datetimeoffset';

Here is the result set.

Data type

Output

time

12:35:29. 1234567

date

2007-05-08

smalldatetime

2007-05-08 12:35:00

datetime

2007-05-08 12:35:29.123

datetime2

2007-05-08 12:35:29. 1234567

datetimeoffset

2007-05-08 12:35:29.1234567 +12:15