I have a table_1 that has column dob which has datatype nvarchar(max). Now I want to check every date whether it is in datetime format or not.
The dates which are in datetime format should be copied to table_2 that has column with a datatype of datetime.
Any help how can I do this?
If you are using SQL Server 2012 or later, then TRY_CONVERT can help here:
SELECT *
FROM yourTable
WHERE TRY_CONVERT(datetime, dob) IS NULL;
This would return every record from your table where the dob text field is in some format which SQL Server cannot natively convert to a datetime.
This will insert all the strings can be converted into Table_2
INSERT INTO Table_2 (DateTimeColumn)
SELECT dob
FROM Table_1
WHERE TRY_CAST(dob AS DATETIME) IS NOT NULL;
It is a very bad habit to store datetime values in a string. The reason why: Date-Time formats differ around the world and depend on your system's culture settings. Even worse, some format depend on a given language. Try this out:
SET LANGUAGE ENGLISH; --try with GERMAN to see the effect on "Decemeber"
SET DATEFORMAT ymd; --try with "ydm" or "dmy"
DECLARE #tbl TABLE(dob NVARCHAR(MAX));
INSERT INTO #tbl VALUES('blah') --just a wrong value
,('20201231') --ISO, "unseparated YMD-format (see CONVERT with 112)
,('2020-12-31') --ISO8601
,('2020-31-12') --European with leading year
,('12-31-2020') --USA (see CONVERT with 110)
,('31-12-2020') --European (see CONVERT with 113)
,('31 December 2020') --language dependant (see CONVERT with 113), try with German "Dezember"
,('2020-02-30'); --Invalid, there's no 30th of February
SELECT t.dob --Your value
,[cast] = TRY_CAST(t.dob AS DATETIME) --CAST relies on the system's settings (might work on your machine but can break on a customer's machine
,[convert] = TRY_CONVERT(DATETIME, t.dob, 112) --CONVERT allows to use the style paramter, better than CAST, but more strict
,[parse] = TRY_PARSE(t.dob AS DATETIME USING 'en-US') --Parsing allows to mention the culture. You do not need to specify the language as a general setting
,[xmlCast] = CAST(t.dob AS XML).value('. cast as xs:date?','datetime') --Works below v2012, but can deal with ISO8601 only.
FROM #tbl t;
Play with the settings
You can use GERMAN instead of ENGLISH. The entry with December will not work any more. You can change the general date format to any combination of ymd and find, that some formats stop to work while others start to work.
TRY_CAST, TRY_CONVERT and TRY_PARSE will need a version of v2012 or higher.
If you are running an older system you should upgrade ( :-) ). The only chance with an older system is a XML hack, but this is very tightly bound to ISO8601.
Finally: For your next question, please try to add more information. State some of your input values, mention your RDBMS with version and try to set up a mockup with DDL and INSERT (look what I've done above).
Hint: Very dangerous...
Try to insert a value like 2020-05-06 and you will find, that some styles read this as the 5th of June, while others return the 6th of May. Returning wrong values is worse than returning NULL or throwing an error...
StayAtHome
StayHealthy
I have a SQL Server 2008 database with a transaction table. There is a field defined as NVARCHAR(16). The data stored is date and time formatted like this:
2016100708593100
I need to write a query that looks at that field and pulls data between two dates
select ... from...where convert(varchar,
convert(datetime,left(a.xact_dati,8)),101)
between '9/29/2016' and '10/05/2016'
I have tried other converts but nothing returns any data. If I use >=getdate()-1
I get data so I should be seeing something returned. Any suggestions?
Replace WHERE Clause with
... WHERE CONVERT(DATETIME,LEFT(a.xact_dati,8)) BETWEEN '9/29/2016' AND '10/05/2016'
Assuming YMD order just
where cast(left('2016100708593100', 8) as date) between '20160929' and '20161005'
Note this clause is not satisfied.
The problem is you're trying to do a date comparison with varchar data.
You go half way to converting the initial value to datetime but then back to varchar.
You could rely on Sql to implicitly convert the between parameters to datetime.
select 'matched',convert(datetime,left('2016100708593100',8),112)
where convert(datetime,left('2016100708593100',8),112) between '2016/09/29' and '2016/10/10'
Take the date part of the string and CAST it as DATE and then compare it with the proper date format.
select ... from...
where cast(left('2016100708593100', 8) as date) between '2016-09-29' and '2016-10-10'
a very straight and fast approach could be to keep this in BIGINT
Something like this:
cast(left(a.xact_dati,8) as bigint) between 20160929 and 20161005
But anyway this will not be sargable and therefore cannot use an index.
You might even stick to varchar, as the YYYYMMDD format is safe with alphanumerical sorting. Cutting a string with LEFT is sargable (AFAIK):
left(a.xact_dati,8) between '20160929' and '20161005'
I have a TimeStamp (varchar(50),null) column in my SQL Server 2008 table which looks misleading by the name TimeStamp. I mean it appears as if it's a datatype timestamp but it's varchar.
But it has values like 201403240004 which looks like a date. Can I convert it into date and use?
Read online that timestamp is only a sequence of numbers and has nothing to do with date and time.
You can.
Providing that the format is YYYYMMDDHHmm, a simple way to do that would be:
SELECT CONVERT(DATETIME,
SUBSTRING([TimeStamp],1,4)+'-'+SUBSTRING([TimeStamp],5,2)+'-'
+SUBSTRING([TimeStamp],7,2)+' '+SUBSTRING([TimeStamp],9,2)+':'
+SUBSTRING([TimeStamp],11,2)+':00.000')
FROM Table
This will take this "timestamp" and first transform it to SQL-readable datetime string, i.e. for your example it would be 2014-03-24 00:04:00.000. Then, it will be easily converted to datetime.
Yes, your column should be convertible to DATETIME, but you may have to do the converison yourself if CONVERT() does support the format.
I can't tell from you example what the time format really is.
If it is YYYYMMDDHHMM them
SELECT CONVERT(DATETIME,LEFT('201403240004',8),112)
+CONVERT(DATETIME,SUBSTRING('201403240004',9,2)+ ':' + RIGHT('201403240004',2)+':00' ,108)
Need to convert this timestamp (001281379300724) to YYYY-MM-DD hh:mm:ss format in SQL Server, if possible. Any suggestions?
This presumes the timestamp is ms since UNIX epoch. It only converts to the nearest second, but you could add ms to it(see below). It has to use two steps since dateadd requires an int. First add minutes by dividing by 60000, then add seconds.
DECLARE #yournum bigint
SET #yournum = 1281379300724
SELECT DATEADD(ss, (#yournum / 1000)%60 , (DATEADD(mi, #yournum/1000/60, '19700101')))
Gives
2010-08-09 18:41:40.000
To get ms precision: (yuck, probably a better way)
DECLARE #yournum bigint
SET #yournum = 1281379300724
SELECT DATEADD(ms, (#yournum%1000),DATEADD(ss, (#yournum / 1000)%60 , (DATEADD(mi, #yournum/1000/60, '19700101'))))
Gives
2010-08-09 18:41:40.723
The simple answer is that if this is a SQL timestamp column (a.k.a rowversion), you can't. Per the documentation for the type:
Each database has a counter that is incremented for each insert or
update operation that is performed on a table that contains a
rowversion column within the database. This counter is the database
rowversion. This tracks a relative time within a database, not an
actual time that can be associated with a clock.
...
The Transact-SQL timestamp data type is different from the timestamp
data type defined in the ISO standard.
You can get slightly closer this way:
SELECT DATEADD(MINUTE, 1281379300724/1000/60, '19700101')
Result:
2010-08-09 18:41:00.000
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?
Try this
Cast('7/7/2011' as datetime)
and
Convert(DATETIME, '7/7/2011', 101)
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.
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.
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.
For this problem the best solution I use is to have a CLR function in Sql Server 2005 that uses one of DateTime.Parse or ParseExact function to return the DateTime value with a specified format.
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
The most upvoted answer here are guravg's and Taptronic's. However, there's one contribution I'd like to make.
The specific format number they showed from 0 to 131 may vary depending on your use-case (see full number list here), the input number can be a nondeterministic one, which means that the expected result date isn't consistent from one SQL SERVER INSTANCE to another, avoid using the cast a string approach for the same reason.
Starting with SQL Server 2005 and its compatibility level of 90,
implicit date conversions became nondeterministic. Date conversions
became dependent on SET LANGUAGE and SET DATEFORMAT starting with
level 90.
Non deterministic values are 0-100, 106, 107, 109, 113, 130. which may result in errors.
The best option is to stick to a deterministic setting, my current preference are ISO formats (12, 112, 23, 126), as they seem to be the most standard for IT people use cases.
Convert(varchar(30), '210510', 12) -- yymmdd
Convert(varchar(30), '20210510', 112) -- yyyymmdd
Convert(varchar(30), '2021-05-10', 23) -- yyyy-mm-dd
Convert(varchar(30), '2021-05-10T17:01:33.777', 126) -- yyyy-mm-ddThh:mi:ss.mmm (no spaces)
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.
Personally if your dealing with arbitrary or totally off the wall formats, provided you know what they are ahead of time or are going to be then simply use regexp to pull the sections of the date you want and form a valid date/datetime component.
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
You can easily achieve this by using this code.
SELECT Convert(datetime, Convert(varchar(30),'10/15/2008 10:06:32 PM',102),102)
This code solve my problem :
convert(date,YOUR_DATE,104)
If you are using timestamp you can you the below code :
convert(datetime,YOUR_DATE,104)
dateadd(day,0,'10/15/2008 10:06:32 PM')