Posted on 2013-05-15
Last Modified: 2013-05-16
@Time is BIGINT.  I need to convert to DATETIME2, but GMT.  I am in CST.

SELECT DATEDIFF(s, '1970-01-01 00:00:00', GETUTCDATE())
Returns:  1368617884
(i tried DATEDIFF(mcs, because we need microseconds format on the BIGINT, but it failed with overflow, saying it was too large.)

DECLARE @Time BIGINT = 1368617884
SELECT dbo.fn_bigintDatetime (@Time)

Result:  1970-01-16 20:10:18.0000000

Of course, my date should be 2013-05-15.....

Does anyone see my error?

CREATE FUNCTION [dbo].[fn_bigintDateTime]
(@Timestamp bigint)
RETURNS datetime2
       DECLARE @GMTDatetime datetime2
       select @GMTDatetime =
       WHEN dateadd(ss, @Timestamp/1000, '1970-01-01')
           Convert(DATETIME, Convert(VARCHAR(4), Year(dateadd(ss, @Timestamp/1000, '1970-01-01') )) + '-03-' + Convert(VARCHAR(2), (31 - (5 * Year(dateadd(ss, @Timestamp/1000, '1970-01-01') )/4 + 4) % 7)) + ' 01:00:00', 20)
           Convert(DATETIME, Convert(VARCHAR(4), Year(dateadd(ss, @Timestamp/1000, '1970-01-01') )) + '-10-' + Convert(VARCHAR(2), (31 - (5 * Year(dateadd(ss, @Timestamp/1000, '1970-01-01') )/4 + 1) % 7)) + ' 02:00:00', 20)
       THEN Dateadd(hh, 1, dateadd(ss, @Timestamp/1000, '1970-01-01'))
       ELSE Dateadd(hh, 0, dateadd(ss, @Timestamp/1000, '1970-01-01'))
RETURN @GMTDatetime    
Question by:dbaSQL
LVL 25

Assisted Solution

by:Lee Savidge
Lee Savidge earned 50 total points
ID: 39167735
So you have a bigint and you want to return the date?

This page has helped me in the past.
LVL 75

Accepted Solution

Anthony Perkins earned 400 total points
ID: 39167786
I am confused.  You want to go from seconds to datetime2, why not simply:
SELECT CAST(DATEADD(SECOND, 1368617884, '19700101') as datetime2)

What am I missing?
LVL 75

Expert Comment

by:Anthony Perkins
ID: 39167796
If that is CST and you want GMT, then something like this::
SELECT CAST(DATEADD(minute, DATEDIFF(minute, GETUTCDATE(), GETDATE()), DATEADD(SECOND, 1368617884, '19700101')) AS datetime2)
U.S. Department of Agriculture and Acronis Access

With the new era of mobile computing, smartphones and tablets, wireless communications and cloud services, the USDA sought to take advantage of a mobilized workforce and the blurring lines between personal and corporate computing resources.

LVL 92

Assisted Solution

by:Patrick Matthews
Patrick Matthews earned 50 total points
ID: 39168114
Word of caution about using the delta between GETDATE and GETUTCDATE...

It will make adjustments for current dates/times, but cannot be relied upon to always yield the right adjustment.

For example, if you use that delta to convert a datetime value from, say, February, but you are making the calculation today, you might be off by an hour because of Daylight Saving Time.

LVL 75

Expert Comment

by:Anthony Perkins
ID: 39168188
Too true.  You are absolutely right.
LVL 17

Author Comment

ID: 39168803
sorry, guys.  insanity.  i will be back soon.
LVL 17

Author Closing Comment

ID: 39170175
You're not missing anything, ac.  i was overthinking it.
this works fine:  DATEADD(s,(@Time/1000),'1/1/1970')

Very good point, matthewspatrick .  And that is definitely something i am going to have to be wary of.

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
sql query help 15 50
MS SQL Server connect issues 4 37
Syntax issue with my Where Clause SQL 2012 20 38
SQL Server Trigger 8 33
Slowly Changing Dimension Transformation component in data task flow is very useful for us to manage and control how data changes in SSIS.
International Data Corporation (IDC) prognosticates that before the current the year gets over disbursing on IT framework products to be sent in cloud environs will be $37.1B.
Using examples as well as descriptions, and references to Books Online, show the documentation available for datatypes, explain the available data types and show how data can be passed into and out of variables.
Viewers will learn how to use the UPDATE and DELETE statements to change or remove existing data from their tables. Make a table: Update a specific column given a specific row using the UPDATE statement: Remove a set of values using the DELETE s…

713 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question