Convert varchar into datetime in SQL Server - sql

How do I convert a string of format mmddyyyy into datetime in SQL Server 2008?
My target column is in DateTime
I have tried with Convert and most of the Date style values however I get an error message:
'The conversion of a varchar data type to a datetime data type resulted in an out-of-range value.'

OP wants mmddyy and a plain convert will not work for that:
select convert(datetime,'12312009')
Msg 242, Level 16, State 3, Line 1
The conversion of a char data type to a datetime data type resulted in
an out-of-range datetime value
so try this:
DECLARE #Date char(8)
set #Date='12312009'
SELECT CONVERT(datetime,RIGHT(#Date,4)+LEFT(#Date,2)+SUBSTRING(#Date,3,2))
OUTPUT:
-----------------------
2009-12-31 00:00:00.000
(1 row(s) affected)

SQL Server can implicitly cast strings in the form of 'YYYYMMDD' to a datetime - all other strings must be explicitly cast. here are two quick code blocks which will do the conversion from the form you are talking about:
version 1 uses unit variables:
BEGIN
DECLARE #input VARCHAR(8), #mon CHAR(2),
#day char(2), #year char(4), #output DATETIME
SET #input = '10022009' --today's date
SELECT #mon = LEFT(#input, 2), #day = SUBSTRING(#input, 3,2), #year = RIGHT(#input,4)
SELECT #output = #year+#mon+#day
SELECT #output
END
version 2 does not use unit variables:
BEGIN
DECLARE #input CHAR(8), #output DATETIME
SET #input = '10022009' --today's date
SELECT #output = RIGHT(#input,4) + SUBSTRING(#input, 3,2) + LEFT(#input, 2)
SELECT #output
END
Both cases rely on sql server's ability to do that implicit conversion.

Likely you have bad data that cannot convert. Dates should never be stored in varchar becasue it will allow dates such as ASAP or 02/30/2009. Use the isdate() function on your data to find the records which can't convert.
OK I tested with known good data and still got the message. You need to convert to a different format becasue it does not know if 12302009 is mmddyyyy or ddmmyyyy. The format of yyyymmdd is not ambiguous and SQL Server will convert it correctly
I got this to work:
cast( right(#date,4) + left(#date,4) as datetime)
You will still get an error message though if you have any that are in a non-standard format like '112009' or some text value or a true out of range date.

I found this helpful for my conversion, without string manipulation. https://learn.microsoft.com/en-us/sql/t-sql/functions/cast-and-convert-transact-sql
CONVERT(VARCHAR(23), #lastUploadEndDate, 121)
yyyy-mm-dd hh:mi:ss.mmm(24h) was the format I needed.

Convert would be the normal answer, but the format is not a recognised format for the converter, mm/dd/yyyy could be converted using convert(datetime,yourdatestring,101) but you do not have that format so it fails.
The problem is the format being non-standard, you will have to manipulate it to a standard the convert can understand from those available.
Hacked together, if you can guarentee the format
declare #date char(8)
set #date = '12312009'
select convert(datetime, substring(#date,5,4) + substring(#date,1,2) + substring(#date,3,2),112)

Look at CAST / CONVERT in BOL that should be a start.
If your target column is datetime you don't need to convert it, SQL will do it for you.
Otherwise
CONVERT(datetime, '20090101')
Should do it.
This is a link that should help as well:

I'd use STUFF to insert dividing chars and then use CONVERT with the appropriate style. Something like this:
DECLARE #dt VARCHAR(100)='111290';
SELECT CONVERT(DATETIME,STUFF(STUFF(#dt,3,0,'/'),6,0,'/'),3)
First you use two times STUFF to get 11/12/90 instead of 111290, than you use the 3 to convert this to datetime (or any other fitting format: use . for german, - for british...) More details on CAST and CONVERT
Best was, to store date and time values properly.
This should be either "universal unseparated format" yyyyMMdd
or (especially within XML) it should be ISO8601: yyyy-MM-dd or yyyy-MM-ddThh:mm:ss More details on ISO8601
Any culture specific format will lead into troubles sooner or later...

use Try_Convert:Returns a value cast to the specified data type if the cast succeeds; otherwise, returns null.
DECLARE #DateString VARCHAR(10) ='20160805'
SELECT TRY_CONVERT(DATETIME,#DateString)
SET #DateString ='Invalid Date'
SELECT TRY_CONVERT(DATETIME,#DateString)
Link:MSDN TRY_CONVERT (Transact-SQL)

I had luck with something similar:
Convert(DATETIME, CONVERT(VARCHAR(2), #Month) + '/' + CONVERT(VARCHAR(2), #Day)
+ '/' + CONVERT(VARCHAR(4), #Year))

The root cause of this issue can be in the regional settings - DB waiting for YYYY-MM-DD while an app sents, for example, DD-MM-YYYY (Russian locale format) as it was in my case. All I did - change locale format from Russian to English (United States) and voilĂ .

This seems the easiest way..
SELECT REPLACE(CONVERT(CHAR(10), GETDATE(), 110),'-','')

SQL standard dates while inserting or updating Must be between 1/1/1753 12:00:00 AM and 12/31/9999 11:59:59 PM.
So if you are inserting/Updating below 1/1/1753 you will get this error.

DECLARE #d char(8)
SET #d = '06082020' /* MMDDYYYY means June 8. 2020 */
SELECT CAST(FORMAT (CAST (#d AS INT), '##/##/####') as DATETIME)
Result returned is the original date string in #d as a DateTime.

Related

difference in the format of output between datetime and datetime2(3) data types when converted to varchar with style 114

There is a difference between the format of DateTime and DateTime2(3) when they are converted to varchar with style 114. The example is as follows:
DECLARE #date1 datetime=GETDATE()
DECLARE #date2 DATETIME2(3)=GETDATE()
SELECT CONVERT(VARCHAR,#date1, 114),CONVERT(VARCHAR,#date2,114)
The output of the above SQL statements is:
14:47:33:820 14:47:33.820
db<>fiddle.uk
So, we can see the difference in the output is ":" in the case of DateTime whereas "." in the case of DateTime2(3).
Is there any solution to get the ":" in the output in the case of datetime2(3)?
The behavior is unexplainable; as a workaround, you can use the FORMAT function to format the date:
DECLARE #date1 DATETIME = SYSDATETIME()
DECLARE #date2 DATETIME2(3) = SYSDATETIME()
SELECT
#date1,
#date2,
FORMAT(#date1, 'HH:mm:ss:fff'),
FORMAT(#date2, 'HH:mm:ss:fff')
I think you can CAST #date2 AS DATETIME before convert to varchar if you want to get the ":" in the output in the case of datetime2(3)
SELECT CONVERT(VARCHAR,#date1, 114),CONVERT(VARCHAR,CAST(#date2 AS DATETIME),114)
In the meantime, format 113 seems to use the colon correctly, so you can use:
RIGHT(CONVERT(VARCHAR(255), #date2, 113), 12)
Note the use of a length with VARCHAR(). My advice is to never use string types in SQL Server without a length. The default length varies by context and not including an explicit length can introduce a hard-to-debug error.

SQL datetime incorrect format when declaring variable

I am trying to figure out why this example does not work as expected. I am using SQL Server 2017.
DECLARE #testDate DATETIME = CONVERT(VARCHAR(10), GETDATE(), 110)
SELECT CONVERT(VARCHAR(10), GETDATE(), 110)
SELECT #testDate
The first select gives the correct format but instead the second select gives incorrect format. The same happens when i try to cast it from NVARCHAR. Can someone explain to me why this is happening? It's like the variable is not properly storing the result of convert.
EDIT: You can see the results below the first select returns a different format than the second one.
EDIT2: Thank you for your answer but my question was quite specific on why those 2 selects return different results and it was mainly educational. Not to analyze all the business requirements, I gave 3 lines and i asked why I am getting those results. Simple as that. What i did not understood/notice was that the datetime object was casting the result of the CONVERT to a different format by itself.
You are converting Varchar to DateTime
See these examples:
DECLARE #testDate2 DATETIME = '08-27-2019'
SELECT #testDate2
DECLARE #testDate3 DATETIME = '2019-08-27'
SELECT #testDate3
SQL always convert values to default DateTime format.
Both of them converted to 2019-08-27 00:00:00.000
In this case SELECT CONVERT(VARCHAR(10), GETDATE(), 110), your selecting formated Nvarchar. style 110 => mm-dd-yyyy
If you want to store converted DateTime you can use like this:
DECLARE #testDate4 VARCHAR(10) = CONVERT(VARCHAR(10), GETDATE(), 110)

SQL Server: how to change data entry from VARCHAR to DATETIME?

I have below sample data:
03202012 as date but the column datatype is Varchar.
I want to convert it to 2012-03-20 00:00:00.000 as Datetime.
I tried using
CAST(CONVERT(CHAR(10), Column, 101) AS DATETIME)
But I get an error:
The conversion of a varchar data type to a datetime data type resulted in an out-of-range value.
Complete code snippet to test:
DECLARE #Column VARCHAR(MAX) = '03202012'
SELECT CAST(CONVERT(CHAR(10), #Column, 101) AS DATETIME)
Use yyyyMMdd format, that always works:
DECLARE #myDateString varchar(10) = '03202012';
SELECT cast( substring(#myDateString, 5, 4)+
substring(#myDateString, 1, 2)+
substring(#myDateString, 3, 2) AS datetime);
I found below script help me solved my concern.
SELECT convert(datetime, STUFF(STUFF('31012016',3,0,'-'),6,0,'-'), 105)
Result: 2016-01-31 00:00:00.000
Thanks all for the effort. :D
In MySQL, you can use the STR_TO_DATE function to convert a string to a date. For your example, it would look like this
STR_TO_DATE("03-02-2012", "%m-%d-%Y");
Note that the format part of the string must match the format part of the date.
Edit: Just found out this is for SQL Server, but I assume this will work there as well.

Convert from nvarchar to DateTime with am pm?

In my table I have myDate column of type nvarchar(50).
The result I need is to select this date/time: 07/11/2013 11:22:07
And I need to get 07/11/2013 11:22:07 am from it (add am/pm to the original date&time).
I tried everything but get only the original data without am/pm.
This is an example from my query :
select convert(dateTime,myDate,100) as Date from Info
or
select convert(dateTime,myDate,0) as Date from Info
What am I missing ?
try this !!
declare #date datetime
set #date='07/11/2013 11:22:07'
SELECT cast(convert(varchar(20),substring(convert(nvarchar(20),#date, 9), 0, 21)
+ ' ' + substring(convert(nvarchar(30), #date, 9), 25, 2),105) as datetime)
Your field is a NVARCHAR field so just return it without any conversion. In your query you convert string representation into the DATETIME type and returns it. Your browser software which shows query results convert DateTime value into string representation to show it to you and conversion format depends on this software usually you can change it changing Windows Regional Settings.
You can get AM/PM data using following query
declare #date datetime
select #date= CAST('07/11/2013 11:22:07' AS datetime)
select RIGHT ( CONVERT(VARCHAR,#date,9),2)

Char to DateTime Conversion

I have one column capturedatetime(Char(30)):
2006-04-25T15:50:59.997000 PM
And I want to convert it and load it at other table column which have is in DateTime. either by T-sql or SSIS which ever way.
I have tried with:
select CONVERT(datetime, '2006-04-25T15:50:59.997000 PM', 126)
But it creates an error:
Conversion failed when converting date and/or time from character string
Late update:
In this column I also have other data that is in a completely different format:
29-JAN-10 08.57.41.000000 PM
(1) STOP storing datetime data in string columns! This is nothing, nothing, nothing but trouble.
(2) Why on earth does your column get data in two different string formats that aren't even valid? Why does the string use 24 hour time and have AM/PM suffix? Why use a regional string format and Y2K disaster like 29-JAN-10?
Here is one way, but it's awfully ugly. I highly recommend you fix the SSIS process to give you valid datetime values in the first place, if not as datetimes, at least as valid ISO strings (yyyy-mm-ddThh:mm:ss.nnn):
DECLARE #x TABLE (d CHAR(30));
INSERT #x SELECT '2006-04-25T15:50:59.997000 PM'
UNION ALL SELECT '29-JAN-10 08.57.41.000000 PM';
SET LANGUAGE ENGLISH; -- this is important, else style 6 may not work
SELECT
CASE WHEN d LIKE '__[0-9]%' THEN
CONVERT(DATETIME, LEFT(d, 23))
WHEN d LIKE '[0-9][0-9]-%' THEN
CONVERT(DATETIME, CONVERT(CHAR(8),
CONVERT(DATETIME,REPLACE(LEFT(d,9),' ','-'),6),112)
+ ' ' + REPLACE(SUBSTRING(d,11,8),'.',':')
+ ' ' + RIGHT(RTRIM(d),2))
END
FROM #x;
The conversion for 126 requires no spaces ... I've got it to work like this:
declare #T varchar(50)
declare #dt datetime
set #T = '2006-04-25T15:50:59.997'
set #dt = convert(datetime,#t,126)
select #T, #dt
select convert(datetime,left('2006-04-25T15:50:59.997000 PM',23))
or
select convert(datetime,left(capturedatetime,23))
If you use cast, you do not even need to supply a format. Code snippet below tested on SQL 2012 Developer version.
declare #var_string varchar(50) = '2006-04-25T15:50:59.997';
declare #var_datetime datetime = cast(#var_string as datetime);
select #var_string as my_string, #var_datetime as my_variable;