How to convert Unix time in microseconds with SQL Server? - sql-server

I've seen a lot on converting Unix time from other formats to datetime, but nothing really from microseconds. How can you SELECT a field this with a timestamp of 1470562081943371 without getting overflows with an output of YYYY-MM-DD HH:MM:SS:MM?

Not sure if this is unit is correct, but...
Declare #UnixTime bigint = 1470562081943371
Select DateAdd(MS,round(((#UnixTime/1000000.)-(#UnixTime/1000000))*1000,0),DateAdd(SECOND,(#UnixTime/1000000),'1970-01-01 00:00:00'))
Returns
2016-08-07 09:28:01.943
Confirmed results with http://www.epochconverter.com/

Related

Display microsends in sql server

How can I display microseconds in SQL SERVER?
I have looked at the CONVERT function which has a lot of options but none with microseconds.
My column is type "datetime";
For microsecond precision you need to use DATETIME2 datatype, there is no way around this.
DATETIME does not store microsecond information, it only stores data up to milisecond and even that is not precise enough down to 1 milisecond.
For a more detailed breakdown on what precision to expect from different time or datetime datatypes have a look here.
an example that seems to illustrate microsecond date arithmetic -note use of DATETIME2 - DATETIME is not accurate even to 1ms - bear in mind SQL getdate may not return values to microsecond accuracy - I don't know where your values are from of course.
declare #dn as datetime2 = getdate();
waitfor delay '00:00:01';
declare #dn2 as datetime2 = getdate();
SELECT datediff(microsecond,#dn,#dn2);

TSQL Datediff from a string

I have a simple query that I am trying to use this select statement on.
I am trying to get the difference in seconds from the date provided (a UNIX timestamp).
select
DATEDIFF(s, '19700101', CAST(CAST('2014-08-27 08:59:56.0000000' AS DATETIME) AS INT))
When I try this, I get the following error :
Conversion failed when converting date and or time from character string.
I figured casting the string as datetime would have resolved that?
First of all, you should try to avoid using shorthands for the datepart, instead of s, use SECOND.
Another good practice when casting a string to a date is to use CONVERT so you can specify the format to use on the conversion (in your case, it would be 121. Finally, for the whole thing to work, you'll need to use less miliseconds (up to 3):
DECLARE #Date VARCHAR(50)
SET #Date = '2014-08-27 08:59:56.0000000'
SELECT DATEDIFF(SECOND,'19700101',CONVERT(DATETIME,LEFT(#Date,23),121))

What date format is this? (001281379300724)

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

How to make SQL Server to save datetime with AM/PM format?

I'm trying to make my SQL Server table datetime columns save datetime with AM/PM. How to make SQL Server to save datetime with AM/PM format?
Right now it saves date like this: 2012-01-23 14:47:00.000
Is it possible to save it 2012-01-23 02:47:00.000 PM ??
Or does SQL Server save the date and time in this format (2012-01-23 14:47:00.000) all the time and I need to convert it just on output and input?
Is it even possible to save it in this format (2012-01-23 02:47:00.000 PM)? Or does SQL Server save datetime in 24 hour format?
thanks indeed for any help. sorry for language. ;)
Internally the date and time are stored as a number.
Whether it's displayed in a 12 or 24 hour clock is up to the program formatting it for display.
As Andrew said, Datetime format is stored not as string. so, you can use CONVERT function to get the datetime value in approprate format. for example,
SELECT CONVERT(VARCHAR(20), GETDATE(), 100)
to learn more about datetime formatting, see this article
AM/PM serves only for visualization, if you need to display them, use CONVERT keyword:
SELECT CONVERT(varchar, YourDateTimeField, 109)
FROM YourTable
If you need to store AM/PM - it is makes no sense for datetime type, use varchar type instead.
You can simply use CONVERT function as following:
select CONVERT(VARCHAR,GETDATE(),108)
http://www.fmsinc.com/free/NewTips/SQL/AM_PM_time_format_in_SQL.asp
http://msdn.microsoft.com/en-us/library/Aa226054
http://blogs.msdn.com/b/kathykam/archive/2006/09/29/773041.aspx
Depending on the accuracy of the datetime you are storing you might be able to clean it up with
REPLACE(CONVERT (varchar, YourDateTimeField, 109), ':00.0000000', ' ')
This will not work if your date field is populated with GETDATE() as that means it will contain seconds and milliseconds but it will work if the field is populated by a user and seconds and milliseconds are all zeros

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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