Cast as Date Only - sql-server

My goal is to display this
02/28/19 63
from this. (date_birth is datetime in DB)
1963-02-28 00:00:00.000
I used this SQL query code
FORMAT(date_birth,'MM/dd/19 yy')
but my teacher wanted it in a cast so I did this
CAST(date_birth as date) as date_birth
How can i format the above date through cast?

Since date_birth is already a DateTime column in the DB, you can chain the function calls and call them together.
Something like this: FORMAT(CAST(date_birth as DATE),'MM/dd/19 yy')
Please note that the order matters here - also, if date_birth is a VARCHAR in the DB, then this might not work as the contents of the string could be different from something a Date could accept.
For info: https://www.sqlservertutorial.net/sql-server-system-functions/convert-datetime-to-date/

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

Convert varchar to datefield in SQL Server

I am aware that this is a very common and have tried using the solutions suggested on similar questions. However, I cant seem to make it work.
I have a column which contains dates, but it is of varchar datatype.
The data looks like this:
startdate
-----------
15/01/2007
29/06/1998
07/12/2001
and so on..
I tried the following command
try_convert(datetime, startdate) as 'startdate'
But it returns a lot of NULLs even when there is a date populated in the original column.
Can someone please help?
The try_convert method accepts three arguments: Data type, Expression, and Style.
You need to use the Style argument:
try_convert(datetime, startdate, 103) as 'startdate' -- 103 is dd/MM/yyyy
(a list of supported styles can be found here)
Also, You should store date values as Date, not as varchar.
For more information, read Aaron Bertrand's Bad habits to kick : choosing the wrong data type

SQL Server date formatting issue

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'

Timestamp confusion in SQL Server

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)

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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