I want to convert a string like this:
'10/15/2008 10:06:32 PM'
into the equivalent DATETIME value in Sql Server.
In Oracle, I would say this:
TO_DATE('10/15/2008 10:06:32 PM','MM/DD/YYYY HH:MI:SS AM')
This question implies that I must parse the string into one of the standard formats, and then convert using one of those codes. That seems ludicrous for such a mundane operation. Is there an easier way?
SQL Server (2005, 2000, 7.0) does not have any flexible, or even non-flexible, way of taking an arbitrarily structured datetime in string format and converting it to the datetime data type.
By "arbitrarily", I mean "a form that the person who wrote it, though perhaps not you or I or someone on the other side of the planet, would consider to be intuitive and completely obvious." Frankly, I'm not sure there is any such algorithm.
Try this
Cast('7/7/2011' as datetime)
and
Convert(varchar(30),'7/7/2011',102)
See CAST and CONVERT (Transact-SQL) for more details.
Run this through your query processor. It formats dates and/or times like so and one of these should give you what you're looking for. It wont be hard to adapt:
Declare @d datetime
select @d = getdate()
select @d as OriginalDate,
convert(varchar,@d,100) as ConvertedDate,
100 as FormatValue,
'mon dd yyyy hh:miAM (or PM)' as OutputFormat
union all
select @d,convert(varchar,@d,101),101,'mm/dd/yy'
union all
select @d,convert(varchar,@d,102),102,'yy.mm.dd'
union all
select @d,convert(varchar,@d,103),103,'dd/mm/yy'
union all
select @d,convert(varchar,@d,104),104,'dd.mm.yy'
union all
select @d,convert(varchar,@d,105),105,'dd-mm-yy'
union all
select @d,convert(varchar,@d,106),106,'dd mon yy'
union all
select @d,convert(varchar,@d,107),107,'Mon dd, yy'
union all
select @d,convert(varchar,@d,108),108,'hh:mm:ss'
union all
select @d,convert(varchar,@d,109),109,'mon dd yyyy hh:mi:ss:mmmAM (or PM)'
union all
select @d,convert(varchar,@d,110),110,'mm-dd-yy'
union all
select @d,convert(varchar,@d,111),111,'yy/mm/dd'
union all
select @d,convert(varchar,@d,12),12,'yymmdd'
union all
select @d,convert(varchar,@d,112),112,'yyyymmdd'
union all
select @d,convert(varchar,@d,113),113,'dd mon yyyy hh:mm:ss:mmm(24h)'
union all
select @d,convert(varchar,@d,114),114,'hh:mi:ss:mmm(24h)'
union all
select @d,convert(varchar,@d,120),120,'yyyy-mm-dd hh:mi:ss(24h)'
union all
select @d,convert(varchar,@d,121),121,'yyyy-mm-dd hh:mi:ss.mmm(24h)'
union all
select @d,convert(varchar,@d,126),126,'yyyy-mm-dd Thh:mm:ss:mmm(no spaces)'
In SQL Server Denali, you will be able to do something that approaches what you're looking for. But you still can't just pass any arbitrarily defined wacky date string and expect SQL Server to accommodate. Here is one example using something you posted in your own answer. The FORMAT() function and can also accept locales as an optional argument - it is based on .Net's format, so most if not all of the token formats you'd expect to see will be there.
DECLARE @d DATETIME = '2008-10-13 18:45:19';
-- returns Oct-13/2008 18:45:19:
SELECT FORMAT(@d, N'MMM-dd/yyyy HH:mm:ss');
-- returns NULL if the conversion fails:
SELECT TRY_PARSE(FORMAT(@d, N'MMM-dd/yyyy HH:mm:ss') AS DATETIME);
-- returns an error if the conversion fails:
SELECT PARSE(FORMAT(@d, N'MMM-dd/yyyy HH:mm:ss') AS DATETIME);
I strongly encourage you to take more control and sanitize your date inputs. The days of letting people type dates using whatever format they want into a freetext form field should be way behind us by now. If someone enters 8/9/2011 is that August 9th or September 8th? If you make them pick a date on a calendar control, then the app can control the format. No matter how much you try to predict your users' behavior, they'll always figure out a dumber way to enter a date that you didn't plan for.
Until Denali, though, I think that @Ovidiu has the best advice so far... this can be made fairly trivial by implementing your own CLR function. Then you can write a case/switch for as many wacky non-standard formats as you want.
UPDATE for @dhergert:
SELECT TRY_PARSE('10/15/2008 10:06:32 PM' AS DATETIME USING 'en-us');
SELECT TRY_PARSE('15/10/2008 10:06:32 PM' AS DATETIME USING 'en-gb');
Results:
2008-10-15 22:06:32.000
2008-10-15 22:06:32.000
You still need to have that other crucial piece of information first. You can't use native T-SQL to determine whether 6/9/2012 is June 9th or September 6th.
Use this:
SELECT convert(datetime, '2018-10-25 20:44:11.500', 121) -- yyyy-mm-dd hh:mm:ss.mmm
And refer to the table in the official documentation for the conversion codes.
Short answer:
SELECT convert(date, '10/15/2011 00:00:00', 101) as [MM/dd/YYYY]
Other date formats can be found at SQL Server Helper > SQL Server Date Formats
Took me a minute to figure this out so here it is in case it might help someone:
In SQL Server 2012 and better you can use this function:
SELECT DATEFROMPARTS(2013, 8, 19);
Here's how I ended up extracting the parts of the date to put into this function:
select
DATEFROMPARTS(right(cms.projectedInstallDate,4),left(cms.ProjectedInstallDate,2),right( left(cms.ProjectedInstallDate,5),2)) as 'dateFromParts'
from MyTable
I know this is a wicked old post with a whole lot of answers but a lot of people think that they NEED to either break things apart and put them back together or they insist that there's no way to implicitly do the conversion the OP original asked for.
To review and to hopefully provide an easy answer to others with the same question, the OP asked how to convert '10/15/2008 10:06:32 PM' to a DATETIME. Now, SQL Server does have some language dependencies for temporal conversions but if the language is english or something similar, this becomes a simple problem... just do the conversion and don't worry about the format. For example (and you can use CONVERT or CAST)...
SELECT UsingCONVERT = CONVERT(DATETIME,'10/15/2008 10:06:32 PM')
,UsingCAST = CAST('10/15/2008 10:06:32 PM' AS DATETIME)
;
... and that produces the follow answers, both of which are correct.
Like they say on the TV commercials, "But wait! Don't order yet! For no extra cost, it can do MUCH more!"
Let's see the real power of temporal conversions with the DATETIME and partially examine the mistake known as DATETIME2. Check out the whacky formats that DATETIME can handle auto-magically and that DATETIME2 cannot. Run the following code and see...
--===== Set the language for this example.
SET LANGUAGE ENGLISH --Same a US-English
;
--===== Use a table constructor as if it were a table for this example.
SELECT *
,DateTimeCONVERT = TRY_CONVERT(DATETIME,StringDT)
,DateTimeCAST = TRY_CAST(StringDT AS DATETIME)
,DateTime2CONVERT = TRY_CONVERT(DATETIME2,StringDT)
,DateTime2CAST = TRY_CAST(StringDT AS DATETIME2)
FROM (
VALUES
('Same Format As In The OP' ,'12/16/2001 01:51:01 PM')
,('Almost Normal' ,'16 December, 2001 1:51:01 PM')
,('More Normal' ,'December 16, 2001 01:51:01 PM')
,('Time Up Front + Spaces' ,' 13:51:01 16 December 2001')
,('Totally Whacky Format #01' ,' 16 13:51:01 December 2001')
,('Totally Whacky Format #02' ,' 16 December 13:51:01 2001 ')
,('Totally Whacky Format #03' ,' 16 December 01:51:01 PM 2001 ')
,('Totally Whacky Format #04' ,' 2001 16 December 01:51:01 PM ')
,('Totally Whacky Format #05' ,' 2001 December 01:51:01 PM 16 ')
,('Totally Whacky Format #06' ,' 2001 16 December 01:51:01 PM ')
,('Totally Whacky Format #07' ,' 2001 16 December 13:51:01 PM ')
,('Totally Whacky Format #08' ,' 2001 16 13:51:01 PM December ')
,('Totally Whacky Format #09' ,' 13:51:01 PM 2001.12/16 ')
,('Totally Whacky Format #10' ,' 13:51:01 PM 2001.December/16 ')
,('Totally Whacky Format #11' ,' 13:51:01 PM 2001.Dec/16 ')
,('Totally Whacky Format #12' ,' 13:51:01 PM 2001.Dec.16 ')
,('Totally Whacky Format #13' ,' 13:51:01 PM 2001/Dec.16')
,('Totally Whacky Format #14' ,' 13:51:01 PM 2001 . 12/16 ')
,('Totally Whacky Format #15' ,' 13:51:01 PM 2001 . December / 16 ')
,('Totally Whacky Format #16' ,' 13:51:01 PM 2001 . Dec / 16 ')
,('Totally Whacky Format #17' ,' 13:51:01 PM 2001 . Dec . 16 ')
,('Totally Whacky Format #18' ,' 13:51:01 PM 2001 / Dec . 16')
,('Totally Whacky Format #19' ,' 13:51:01 PM 2001 . Dec - 16 ')
,('Totally Whacky Format #20' ,' 13:51:01 PM 2001 - Dec - 16 ')
,('Totally Whacky Format #21' ,' 13:51:01 PM 2001 - Dec . 16')
,('Totally Whacky Format #22' ,' 13:51:01 PM 2001 - Dec / 16 ')
,('Totally Whacky Format #23' ,' 13:51:01 PM 2001 / Dec - 16')
,('Just the year' ,' 2001 ')
,('YYYYMM' ,' 200112 ')
,('YYYY MMM' ,'2001 Dec')
,('YYYY-MMM' ,'2001-Dec')
,('YYYY . MMM' ,'2001 . Dec')
,('YYYY / MMM' ,'2001 / Dec')
,('YYYY - MMM' ,'2001 / Dec')
,('Forgot The Spaces #1' ,'2001December26')
,('Forgot The Spaces #2' ,'2001Dec26')
,('Forgot The Spaces #3' ,'26December2001')
,('Forgot The Spaces #4' ,'26Dec2001')
,('Forgot The Spaces #5' ,'26Dec2001 13:51:01')
,('Forgot The Spaces #6' ,'26Dec2001 13:51:01PM')
,('Oddly, this doesn''t work' ,'2001-12')
,('Oddly, this doesn''t work' ,'12-2001')
) v (Description,StringDT)
;
So, yeah... SQL Server DOES actually have a pretty flexible method of handling all sorts of weird-o temporal formats and no special handling is required. We didn't even need to remove the "PM"s that were added to the 24 hour times. It's "PFM" (Pure Freakin' Magic).
Things will vary a bit depending on the the LANGUAGE is that you've selected for your server but a whole lot of it will be handled either way.
And these "auto-magic" conversions aren't something new. They go a real long way back.
This page has some references for all of the specified datetime conversions available to the CONVERT function. If your values don't fall into one of the acceptable patterns, then I think the best thing is to go the ParseExact route.
If you want SQL Server to try and figure it out, just use CAST CAST('whatever' AS datetime) However that is a bad idea in general. There are issues with international dates that would come up. So as you've found, to avoid those issues, you want to use the ODBC canonical format of the date. That is format number 120, 20 is the format for just two digit years. I don't think SQL Server has a built-in function that allows you to provide a user given format. You can write your own and might even find one if you search online.
convert string to datetime in MSSQL implicitly
create table tmp
(
ENTRYDATETIME datetime
);
insert into tmp (ENTRYDATETIME) values (getdate());
insert into tmp (ENTRYDATETIME) values ('20190101'); --convert string 'yyyymmdd' to datetime
select * from tmp where ENTRYDATETIME > '20190925' --yyyymmdd
select * from tmp where ENTRYDATETIME > '20190925 12:11:09.555'--yyyymmdd HH:MIN:SS:MS
