How to convert DateTime to VarChar

问题:

I am working on a query in Sql Server 2005 where I need to convert a value in DateTime variable into a varchar variable in yyyy-mm-dd format (without time part). How do I do that?

回答1:

With Microsoft Sql Server:

--
-- Create test case
--
DECLARE @myDateTime DATETIME
SET @myDateTime = '2008-05-03'

--
-- Convert string
--
SELECT LEFT(CONVERT(VARCHAR, @myDateTime, 120), 10)

回答2:

Here's some test sql for all the styles.

DECLARE @now datetime
SET @now = GETDATE()
select convert(nvarchar(MAX), @now, 0) as output, 0 as style 
union select convert(nvarchar(MAX), @now, 1), 1
union select convert(nvarchar(MAX), @now, 2), 2
union select convert(nvarchar(MAX), @now, 3), 3
union select convert(nvarchar(MAX), @now, 4), 4
union select convert(nvarchar(MAX), @now, 5), 5
union select convert(nvarchar(MAX), @now, 6), 6
union select convert(nvarchar(MAX), @now, 7), 7
union select convert(nvarchar(MAX), @now, 8), 8
union select convert(nvarchar(MAX), @now, 9), 9
union select convert(nvarchar(MAX), @now, 10), 10
union select convert(nvarchar(MAX), @now, 11), 11
union select convert(nvarchar(MAX), @now, 12), 12
union select convert(nvarchar(MAX), @now, 13), 13
union select convert(nvarchar(MAX), @now, 14), 14
--15 to 19 not valid
union select convert(nvarchar(MAX), @now, 20), 20
union select convert(nvarchar(MAX), @now, 21), 21
union select convert(nvarchar(MAX), @now, 22), 22
union select convert(nvarchar(MAX), @now, 23), 23
union select convert(nvarchar(MAX), @now, 24), 24
union select convert(nvarchar(MAX), @now, 25), 25
--26 to 99 not valid
union select convert(nvarchar(MAX), @now, 100), 100
union select convert(nvarchar(MAX), @now, 101), 101
union select convert(nvarchar(MAX), @now, 102), 102
union select convert(nvarchar(MAX), @now, 103), 103
union select convert(nvarchar(MAX), @now, 104), 104
union select convert(nvarchar(MAX), @now, 105), 105
union select convert(nvarchar(MAX), @now, 106), 106
union select convert(nvarchar(MAX), @now, 107), 107
union select convert(nvarchar(MAX), @now, 108), 108
union select convert(nvarchar(MAX), @now, 109), 109
union select convert(nvarchar(MAX), @now, 110), 110
union select convert(nvarchar(MAX), @now, 111), 111
union select convert(nvarchar(MAX), @now, 112), 112
union select convert(nvarchar(MAX), @now, 113), 113
union select convert(nvarchar(MAX), @now, 114), 114
union select convert(nvarchar(MAX), @now, 120), 120
union select convert(nvarchar(MAX), @now, 121), 121
--122 to 125 not valid
union select convert(nvarchar(MAX), @now, 126), 126
union select convert(nvarchar(MAX), @now, 127), 127
--128, 129 not valid
union select convert(nvarchar(MAX), @now, 130), 130
union select convert(nvarchar(MAX), @now, 131), 131
--132 not valid
order BY style

Here's the result

output                   style
Apr 28 2014  9:31AM          0
04/28/14                     1
14.04.28                     2
28/04/14                     3
28.04.14                     4
28-04-14                     5
28 Apr 14                    6
Apr 28, 14                   7
09:31:28                     8
Apr 28 2014  9:31:28:580AM   9
04-28-14                     10
14/04/28                     11
140428                       12
28 Apr 2014 09:31:28:580     13
09:31:28:580                 14
2014-04-28 09:31:28          20
2014-04-28 09:31:28.580      21
04/28/14  9:31:28 AM         22
2014-04-28                   23
09:31:28                     24
2014-04-28 09:31:28.580      25
Apr 28 2014  9:31AM          100
04/28/2014                   101
2014.04.28                   102
28/04/2014                   103
28.04.2014                   104
28-04-2014                   105
28 Apr 2014                  106
Apr 28, 2014                 107
09:31:28                     108
Apr 28 2014  9:31:28:580AM   109
04-28-2014                   110
2014/04/28                   111
20140428                     112
28 Apr 2014 09:31:28:580     113
09:31:28:580                 114
2014-04-28 09:31:28          120
2014-04-28 09:31:28.580      121
2014-04-28T09:31:28.580      126
2014-04-28T09:31:28.580      127
28 جمادى الثانية 1435  9:31:28:580AM    130
28/06/1435  9:31:28:580AM    131

Make nvarchar(max) shorter to trim the time. For example:

select convert(nvarchar(11), GETDATE(), 0)
union select convert(nvarchar(max), GETDATE(), 0)

outputs:

May 18 2018
May 18 2018  9:57AM

回答3:

Try the following:

CONVERT(varchar(10), [MyDateTimecolumn], 20)

For a full date time and not just date do:

CONVERT(varchar(23), [MyDateTimecolumn], 121)

See this page for convert styles:

http://msdn.microsoft.com/en-us/library/ms187928.aspx
OR
SQL Server CONVERT() Function

回答4:

SQL Server 2012 has a new function , FORMAT: http://msdn.microsoft.com/en-us/library/ee634924.aspx

and you can use custom date time format strings: http://msdn.microsoft.com/en-us/library/ee634398.aspx

These pages imply it is also available on SQL2008R2, but I don't have one handy to test if that's the case.

Example usage (Australian datetime):

FORMAT(VALUE,'dd/MM/yyyy h:mm:ss tt')

回答5:

Either Cast or Convert:

Syntax for CAST:

CAST ( expression AS data_type [ (length ) ])

Syntax for CONVERT:

CONVERT ( data_type [ ( length ) ] , expression [ , style ] )

http://msdn.microsoft.com/en-us/library/ms187928.aspx

Actually since you asked for a specific format:

REPLACE(CONVERT(varchar(10), Date, 102), '.', '-')

回答6:

You can use DATEPART(DATEPART, VARIABLE). For example:

DECLARE @DAY INT 
DECLARE @MONTH INT
DECLARE @YEAR INT
DECLARE @DATE DATETIME
@DATE = GETDATE()
SELECT @DAY = DATEPART(DAY,@DATE)
SELECT @MONTH = DATEPART(MONTH,@DATE)
SELECT @YEAR = DATEPART(YEAR,@DATE)

回答7:

-- This gives you the time as 0 in format 'yyyy-mm-dd 00:00:00.000'

SELECT CAST( CONVERT(VARCHAR, GETDATE(), 101) AS DATETIME) ; 

回答8:

With Microsoft SQL Server:

Use Syntax for CONVERT:

CONVERT ( data_type [ ( length ) ] , expression [ , style ] )

Example:

SELECT CONVERT(varchar,d.dateValue,1-9)

For the style you can find more info here: MSDN - Cast and Convert (Transact-SQL).

回答9:

Try:

select replace(convert(varchar, getdate(), 111),'/','-');

More on ms sql tips

回答10:

Try the following:

CONVERT(VARCHAR(10),GetDate(),102)

Then you would need to replace the "." with "-".

Here is a site that helps http://www.mssqltips.com/tip.asp?tip=1145

回答11:

declare @dt datetime

set @dt = getdate()

select convert(char(10),@dt,120) 

I have fixed data length of char(10) as you want a specific string format.

回答12:

The OP mentioned datetime format. For me, the time part gets in the way.
I think it's a bit cleaner to remove the time portion (by casting datetime to date) before formatting.

convert( varchar(10), convert( date, @yourDate ) , 111 )

回答13:

This is how I do it: CONVERT(NVARCHAR(10), DATE1, 103) )

回答14:

You can convert your date in many formats, the syntaxe is simple to use :

CONVERT('TheTypeYouWant', 'TheDateToConvert', 'TheCodeForFormating' * )
CONVERT(NVARCHAR(10), DATE_OF_DAY, 103) => 15/09/2016

• The code is an integer, here 3 is the third formating without century, if you want the century just change the code to 103.

In your case, i've just converted and restrict size by nvarchar(10) like this :

CONVERT(NVARCHAR(10), MY_DATE_TIME, 120) => 2016-09-15

See more at : http://www.w3schools.com/sql/func_convert.asp

Another solution (if your date is a Datetime) is a simple CAST :

CAST(MY_DATE_TIME as DATE) => 2016-09-15

回答15:

Try this SQL:

select REPLACE(CONVERT(VARCHAR(24),GETDATE(),103),'/','_') + '_'+ 
       REPLACE(CONVERT(VARCHAR(24),GETDATE(),114),':','_')

回答16:

For SQL Server 2008+ You can use CONVERT and FORMAT together.

For example, for European style (e.g. Germany) timestamp:

CONVERT(VARCHAR, FORMAT(GETDATE(), 'dd.MM.yyyy HH:mm:ss', 'de-DE'))

回答17:

You did not say which database, but with mysql here is an easy way to get a date from a timestamp (and the varchar type conversion should happen automatically):

mysql> select date(now());
+-------------+
| date(now()) |
+-------------+
| 2008-09-16  | 
+-------------+
1 row in set (0.00 sec)

回答18:

The shortest and the simplest way is :

DECLARE @now AS DATETIME = GETDATE()

SELECT CONVERT(VARCHAR, @now, 23)

回答19:

DECLARE @DateTime DATETIME
SET @DateTime = '2018-11-23 10:03:23'
SELECT CONVERT(VARCHAR(100),@DateTime,121 )

回答20:

CONVERT(VARCHAR, GETDATE(), 23)

回答21:

You don't say what language but I am assuming C#/.NET because it has a native DateTime data type. In that case just convert it using the ToString method and use a format specifier such as:

DateTime d = DateTime.Today;
string result = d.ToString("yyyy-MM-dd");

However, I would caution against using this in a database query or concatenated into a SQL statement. Databases require a specific formatting string to be used. You are better off zeroing out the time part and using the DateTime as a SQL parameter if that is what you are trying to accomplish.