unable to convert varchar to date in sql server - sql-server

in my data a column called 'duedate' which is in the varchar(5) format has dates stored in the following format '20110725' for 25th july 2011, is there a way in which i can convert this to date format
i tried using
cast(duedate as datetime)
which did not work
then i tried to convert it to bigint and then to datetime
cast( cast(duedate as bigint) as datetime)
which said
arithematic overflow error
Sorry for the confusion it was varchar(50) - typo error, and thanks a lot for the help ill try the things you guys mentioned

If the column is really varchar(5), then it can't have values like '20110725', because that would be 8 characters.
Maybe the values were truncated when they were inserted?
'20110725' shortened to 5 characters becomes '20117', and converting that won't work.
I guess the problem is something like that, because as Mladen Prajdic already said, converting '20110725' to datetime works perfectly.

Please see this table of valid date-time conversion codes. The code you will need is 112 which converts from yyyymmdd format.
CONVERT (datetime, duedate, 112)

how didn't it work? doing SELECT cast('20110725' as datetime) works perfectly for me.

Try running this on your table to find the values that aren't dates:
SELECT duedate
FROM your_table
WHERE ISDATE(duedate) = 0;
Like Christian said, a VarChar(5) won't be able to hold the value you're expecting it to either.

Related

Varchar(255) as MM/DD/YYYY HH:MM to Datetime format - SQL Server

I know there are a million of these date conversion questions, but I can't find the specific one to solve my problem.
I have a table with a column [Date] that contains data that is formatted as MM/DD/YYYY HH:MM, but is stored as a varchar.
[Date] (varchar(255),null)
12/22/2017 0:34
12/21/2017 21:33
12/21/2017 21:17
...
I need to run a query and filter by date range, so I need to figure out how to convert to a usable datetime format.
I've tried
WHERE CONVERT(VARCHAR(255), CAST([Date] AS DATETIME), 121) between #beg1 and #end1
But get the error
The conversion of a varchar data type to a datetime data type resulted in an out-of-range value.
I've tried several other answers, but none were quite formatted the same as my data so the conversions didn't work.
Any help would be greatly appreciated
As many of us have mentioned, to real solution is fix the data type, which means altering the database.
First, to fix the data, you need to change the format to an ISO format, specifically here we're going to do with the ISO8601 format (yyyy-mm-ddThh:mi:ss.mmm). This will require a TRY_CONVERT and CONVERT (the first to change the data to a smalldatetime and the second to the formatted varchar):
UPDATE dbo.YourTable
SET YourDate = CONVERT(varchar(20),TRY_CONVERT(smalldatetime, YourDate, 101), 126);
Now we can alter the data type (to a smalldatetime as your data is accurate to a minute:
ALTER TABLE dbo.YourTable ALTER COLUMN YourDate smalldatetime NULL;
If you "must" leave it at a varchar (this is a bad idea, as your data has so many problems is so), then you need to use TRY_CONVERT in the WHERE, with the correct style code:
WHERE TRY_CONVERT(smalldatetime, YourDate, 101)
This is, however, a really bad idea as your data is severely flawed. For example, according to your data, the "date" '12/22/2017 0:34' is after today ('09/30/2020 21:25'), not before.
The code as you wrote it works fine. You probably have a badly formatted record or record where it is not in a date format. Try code like this to find those records. Any columns with a "NULL" value are ones where the try_cast could not succeed. These are the ones blowing up your query.
You can then choose to correct these values or simply exclude them from your query.
SELECT
[DateText], try_cast([DateText] AS Datetime) FROM Dates

Troubleshoot conversion failed when converting date and /or time from character string

I know this has been addressed 1000 times but something screwy is going on and I need help with ideas to troubleshoot.
Using MS SQL Server 2012
I have a date stored as INT in the YYYYMMDD format.
I need to turn that into a date and I always use this:
CONVERT(DATE,CONVERT(VARCHAR,YYYYMMDD),101)
*I know not specifying the length of the varchar is bad form but where I'm doing this has never caused an issue and just to be thorough I tried it anyway to no avail.
That conversion always works. Always, until today.
Today, this conversion doesn't work and I get the above mentioned error in title.
One thing I've done is run part of the query to look at the values to make sure I don't find something dumb like this in my values:
20170102
20170304
-->2017ABCD
20170704
What else can I do?
To expand on my initial comment
Example
Declare #YourTable table (SomeCol varchar(25))
Insert Into #YourTable values
('20170102'),
('20170304'),
('2017ABCD'),
('20170704')
Select SomeCol
,AsDate = try_convert(date,SomeCol)
From #YourTable
Returns
SomeCol AsDate
20170102 2017-01-02
20170304 2017-03-04
2017ABCD NULL
20170704 2017-07-04

SQL Server convert ' dd/MM/YYYY H:mm:ss p.m..' to datetime

I am importing a text column into a SQL Server 2008 database.
I have a field 'carcassdate' in the following format
'11/05/2017 9:18:46 a.m.'
'10/05/2017 1:08:27 p.m.'
etc. How can I convert this into a proper SQL Server 2008 datetime (24 hour) column please?
I can't seem to find a proper solution for this.
My desired result is
'11/05/2017 9:18:46 a.m.' converted to 2017-05-11 09:18:46.000
'10/05/2017 1:08:27 p.m.' converted to 2017-05-10 13:08:27.000
Thanks in advance.
What I have tried so far:
strip the date part of the column
select convert(date, convert(varchar(10),carcass_date)) as carcassdate
That's the easy part..But I'm struggling with the time part.
Thanks for your help in advance.
The issue is with the periods in the string. By removing them, you can cast the string as a datetime. e.g.:
SELECT CAST(REPLACE(carcass_date, '.', '') AS DATETIME)
When it comes to date conversion, I suggest that you always be explicit.
Any kind of programming that is not explicit about date formats invites bugs.
I suggest you Never use cast as there is no explicit format. Even though it always assumes ISO format, I've never found any info about how it decides other formats (including your which is not ISO)
Never use convert without a format number.
I suggest you instead use convert with a format number. On my system, this returns two different dates. Cast returns the wrong one.
DECLARE #D AS VARCHAR(100) = '05/11/2017 9:18:46 a.m.'
SELECT CONVERT(DATETIME, REPLACE(#D, '.', ''), 103) as converted
SELECT CAST(REPLACE(#D, '.', '') AS DATETIME) as casted
Number 103 is defined as dd/mm/yyyy format. At least this way you have some degree of self documentation - that's the format you expect
Later versions of SQL have parse but it uses cultures, not format strings.
Perhaps read this
https://www.simple-talk.com/sql/t-sql-programming/how-to-get-sql-server-dates-and-times-horribly-wrong/
There's also a non-decisive discussion here:
datetime Cast or Convert?

Converting a string to a datetime in SQL Server 2008

Simple question cannot seem to get right.
I have a table with a date in this format 20/09/2012 as varchar.
I need to convert to a datetime
Tried various solutions but cannot get it right.
Any suggestions?
Thanks
Using the CONVERT function with style 103 (British/European) seems to work for me:
DECLARE #input VARCHAR(20) = '20/09/2012'
SELECT
CONVERT(DATETIME, #input, 103)
With this approach, you could convert all your VARCHAR dates to their proper datatype - DATETIME - and store them as DATETIME in the first place ....
See Aaron Bertrand great blog post on bad habits to kick : mis-handling date / range queries for more background info on why it's really really bad to keep storing dates as VARCHAR columns ....

How to convert SQL Server's timestamp column to datetime format

As SQL Server returns timestamp like 'Nov 14 2011 03:12:12:947PM', is there some easy way to convert string to date format like 'Y-m-d H:i:s'.
So far I use
date('Y-m-d H:i:s',strtotime('Nov 14 2011 03:12:12:947PM'))
SQL Server's TIMESTAMP datatype has nothing to do with a date and time!
It's just a hexadecimal representation of a consecutive 8 byte integer - it's only good for making sure a row hasn't change since it's been read.
You can read off the hexadecimal integer or if you want a BIGINT. As an example:
SELECT CAST (0x0000000017E30D64 AS BIGINT)
The result is
400756068
In newer versions of SQL Server, it's being called RowVersion - since that's really what it is. See the MSDN docs on ROWVERSION:
Is a data type that exposes automatically generated, unique binary numbers within a database. rowversion is generally used as a mechanism
for version-stamping table rows. The
rowversion data type is just an incrementing number and does not
preserve a date or a time. To record a date or time, use a datetime2
data type.
So you cannot convert a SQL Server TIMESTAMP to a date/time - it's just not a date/time.
But if you're saying timestamp but really you mean a DATETIME column - then you can use any of those valid date formats described in the CAST and CONVERT topic in the MSDN help. Those are defined and supported "out of the box" by SQL Server. Anything else is not supported, e.g. you have to do a lot of manual casting and concatenating (not recommended).
The format you're looking for looks a bit like the ODBC canonical (style = 121):
DECLARE #today DATETIME = SYSDATETIME()
SELECT CONVERT(VARCHAR(50), #today, 121)
gives:
2011-11-14 10:29:00.470
SQL Server 2012 will finally have a FORMAT function to do custom formatting......
The simplest way of doing this is:
SELECT id,name,FROM_UNIXTIME(registration_date) FROM `tbl_registration`;
This gives the date column atleast in a readable format.
Further if you want to change te format click here.
Using cast you can get date from a timestamp field:
SELECT CAST(timestamp_field AS DATE) FROM tbl_name
Works fine, except this message:
Implicit conversion from data type varchar to timestamp is not allowed. Use the CONVERT function to run this query
So yes, TIMESTAMP (RowVersion) is NOT a DATE :)
To be honest, I fidddled around quite some time myself to find a way to convert it to a date.
Best way is to convert it to INT and compare. That's what this type is meant to be.
If you want a date - just add a Datetime column and live happily ever after :)
cheers mac
My coworkers helped me with this:
select CONVERT(VARCHAR(10), <tms_column>, 112), count(*)
from table where <tms_column> > '2012-09-10'
group by CONVERT(VARCHAR(10), <tms_column>, 112);
or
select CONVERT(DATE, <tms_column>, 112), count(*)
from table where <tms_column> > '2012-09-10'
group by CONVERT(DATE, <tms_column>, 112);
"You keep using that word. I do not think it means what you think it means."
— Inigo Montoya
The timestamp has absolutely no relationship to time as marc_s originally said.
declare #Test table (
TestId int identity(1,1) primary key clustered
,Ts timestamp
,CurrentDt datetime default getdate()
,Something varchar(max)
)
insert into #Test (Something)
select name from sys.tables
waitfor delay '00:00:10'
insert into #Test (Something)
select name from sys.tables
select * from #Test
Notice in the output that Ts (hex) increments by one for each record, but the actual time has a gap of 10 seconds. If it were related to time then there would be a gap in the timestamp to correspond with the difference in the time.
for me works:
TO_DATE('19700101', 'yyyymmdd') + (TIME / 24 / 60 / 60)
(oracle DB)
Robert Mauro has the correct comment. For those who know the Sybase origins, datetime was really two separate integers, one for date, one for time, so timestamp aka rowversion could just be considered the raw value captured from the server. Much faster.
After impelemtation of conversion to integer
CONVERT(BIGINT, [timestamp]) as Timestamp
I've got the result like
446701117
446701118
446701119
446701120
446701121
446701122
446701123
446701124
446701125
446701126
Yes, this is not a date and time, It's serial numbers
Why not try FROM_UNIXTIME(unix_timestamp, format)?
I had the same problem with timestamp eg:'29-JUL-20 04.46.42.000000000 PM'. I wanted to turn it into 'yyyy-MM-dd' format. The solution that finally works for me is
SELECT TO_CHAR(mytimestamp, 'YYYY-MM-DD') FROM mytable;
I will assume that you've done a data dump as insert statements, and you (or whoever Googles this) are attempting to figure out the date and time, or translate it for use elsewhere (eg: to convert to MySQL inserts). This is actually easy in any programming language.
Let's work with this:
CAST(0x0000A61300B1F1EB AS DateTime)
This Hex representation is actually two separate data elements... Date and Time. The first four bytes are date, the second four bytes are time.
The date is 0x0000A613
The time is 0x00B1F1EB
Convert both of the segments to integers using the programming language of your choice (it's a direct hex to integer conversion, which is supported in every modern programming language, so, I will not waste space with code that may or may not be the programming language you're working in).
The date of 0x0000A613 becomes 42515
The time of 0x00B1F1EB becomes 11661803
Now, what to do with those integers:
Date
Date is since 01/01/1900, and is represented as days. So, add 42,515 days to 01/01/1900, and your result is 05/27/2016.
Time
Time is a little more complex. Take that INT and do the following to get your time in microseconds since midnight (pseudocode):
TimeINT=Hex2Int(HexTime)
MicrosecondsTime = TimeINT*10000/3
From there, use your language's favorite function calls to translate microseconds (38872676666.7 µs in the example above) into time.
The result would be 10:47:52.677
Some of them actually does covert to a date-time from SQL Server 2008 onwards.
Try the following SQL query and you will see for yourself:
SELECT CAST (0x00009CEF00A25634 AS datetime)
The above will result in 2009-12-30 09:51:03:000 but I have encountered ones that actually don't map to a date-time.
Not sure if I'm missing something here but can't you just convert the timestamp like this:
CONVERT(VARCHAR,CAST(ZEIT AS DATETIME), 110)

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