I have a date emp_date which is of type datetime offset. This date is saved correctly in the database.
I want to retrieve all data having the date emp_date less than the actual time, including time zone.
For example, if the emp_date is as below:
2019-10-25 23:44:09.5798885 +14:00
And I am in a time zone of +2, then the data having the above date should not be retrieved.
Any idea of how to do this?
I want to pass the timezone of the user as parameter.
https://dzone.com/articles/dates-and-times-in-sql-server-at-time-zone
pass the needed time zone as parameter, then we can convert to the needed time zone.
DECLARE #TimeZone varchar(50)
SET #TimeZone = 'Central European Standard Time'
SELECT getdate() AT TIME ZONE #TimeZone AS date
SELECT getdate() AT TIME ZONE 'Central European Standard Time' AS date
Related
I am new to SQL and I want to add/subtract the offset value into the DateTime and return new date.
Currently, I am using this
SELECT
GETUTCDATE() AS UTCDate,
GETUTCDATE() AT TIME ZONE 'Eastern Standard Time'
which returns these values:
Current Result : 2021-12-28 07:19:39.320 -05:00
Expected Result : 2021-12-28 02:19:39.320
How can I achieve this? Any help would be appreciated. Thanks
You can use DATEADD and DATEDIFF function:
SELECT GETUTCDATE() AS UTCDate, GETUTCDATE() AT TIME ZONE 'Eastern
Standard Time' ,
DATEADD(MINUTE, DATEDIFF(MINUTE ,GETUTCDATE(), GETUTCDATE() AT TIME ZONE
'Eastern Standard Time')*-1, GETUTCDATE())
GETUTCDATE() returns datetime type. You can use SYSDATETIMEOFFSET() instead to get datetimeoffset and convert it to a desired timezone.
SELECT
SYSDATETIMEOFFSET() AS UTCDate_with_timezone,
SYSDATETIMEOFFSET() AT TIME ZONE 'Eastern Standard Time';
When AT TIME ZONE operator is applied to datetime value it does not change the value, you just inform the system what is the timezone. And this timezone will be just appended to the value.
I felt like this should be easy but I'm not finding answer. The query below will give me the current date/time in California and represent it as UTC with a timezone offset (currently -08:00):
select getdate() at time zone 'Pacific Standard Time'
I simply want to apply the offset and get a timestamp showing the current local time and then drop the offset. I feel like there should be a way to achieve this without having to pick through it with string and date functions. For example, I want to go from
2021-11-24 18:03:41.190 -08:00
to
2021-11-24 10:03:41.190
Is there a succinct way to do this?
When you use AT TIME ZONE on a value that isn't a datetimeoffset it's assumed that the value is at the time zone you are converting it to.
Instead, therefore, you could nest the AT TIME ZONE clauses. If you did do this though, I would also suggest using SYSUTCDATE rather than GETDATE (which returns the local time to the host, which could be any timezone).
SELECT SYSUTCDATETIME() AT TIME ZONE 'UTC' AT TIME ZONE 'Pacific Standard Time';
Though really, just use SYSDATETIMEOFFSET to start with; then you just need one AT TIME ZONE as the RDBMS already knows what timezone the value is for.
SELECT SYSDATETIMEOFFSET() AT TIME ZONE 'Pacific Standard Time';
db<>fiddle
Declare #myDateTime datetime = '2021-11-24 21:35:25.984'; --UTC time
Select cast(#myDateTime At Time Zone 'UTC' At Time Zone 'Pacific Standard Time' As datetime);
Or - you can just apply the desired offset and convert back to datetime
Select cast(switchoffset(#myDateTime, '-08:00') As datetime)
The problem with using switchoffset is that it isn't DST aware and would need to be changed to use a different offset value. If you change the date above to October - the PST time would be 14:35:25.983 but the second calculation still returns 13:35:25.983
I wrote the following query on a SQL Server DB to convert a datetime column to a UTC date column.
select datetime
, dateadd(minute,-datepart(tz,datetime),datetime) datetime_dt_utc
from table1
But I get the same same datetime for both columns.
What do I have to change to make it work?
Please try this:
DATEADD(hh, DATEDIFF(hh, GETDATE(), GETUTCDATE()), datetime)
The GETDATE() will return the current time
The GETUTCDATE() will retunr the current UTC time
The DATEDIFF function will calculate the difference between this two datetimes in hours
The DATEADD function will add this hours to your current datetime.
Another way is via usign the AT TIME ZONE
SELECT datetime AT TIME ZONE 'UTC' from table1
You can check your time zone with:
select CURRENT_TIMEZONE ( )
And use this:
SELECT datetime AT TIME ZONE 'Pacific Standard Time' AT TIME ZONE 'UTC'
from table1
If you are in 'Pacific Standard Time' timezone
I want to calculate Datetime at given timezone based on Datetime in UTC.
I thought that I can do it with the following:
DECLARE #timeUTC DATETIME = '2019-01-01 10:00:00'
SELECT
#timeUTC AS timeUTC,
#timeUTC AT TIME ZONE 'Central European Standard Time' as at_time_zone_offset,
CONVERT(datetime, #timeUTC AT TIME ZONE 'Central European Standard Time',1) at_timezone_convert
-- OUTPUT
---timeUTC |at_time_zone_offset |at_timezone_convert
---2019-01-01 10:00:00.000 |2019-01-01 10:00:00.000 +01:00 |2019-01-01 09:00:00.000
The problem is that result of at_timezone_convert is incorrect- when at UTC time is 10:00, then time +1 is 11:00, not 9.
How can I get the result to be 2019-01-01 11:00:00.000?
At time zone documentation clearly states:
Converts an inputdate to the corresponding datetimeoffset value in the target time zone. When inputdate is provided without offset information, the function applies the offset of the time zone assuming that inputdate is in the target time zone. If inputdate is provided as a datetimeoffset value, then AT TIME ZONE clause converts it into the target time zone using the time zone conversion rules.
(emphasis mine)
If you'll declare #timeUTC as DateTimeOffset and not as DateTime you'll get different results - also, note that once you've converted the DateTimeOffset back to DateTime you'll get funky results.
Also, please note that the yyyy-mm-dd hh:mm:ss string representation format is a localized format when working with DateTime - that is not the case with the newer DateTime2 data type, which is one more reason why you should never work with DateTime again.
See a demo on DB<>Fiddle
Here's a trick I use from time to time:
DECLARE #timeUTC DATETIME = '2019-01-01 10:00:00'
SELECT #timeUTC
AS timeUTC, #timeUTC
AT TIME ZONE 'UTC'
AT TIME ZONE 'Central European Standard Time'
as at_time_zone_offset
Why does this work? Your original datetime has no offset information attached to it (other posters here have explained what the default is when this is the case) The first at time zone clause tells SQL Server "this datetime represents a time in UTC" and outputs a datetimeoffset data type. The second at time zone clause then tells it to convert it to your desired time zone.
Supplying the input as a datetimeoffset the AT TIME ZONE hint will convert to the input to the target time zone.
The snippet below is a simple example:
DECLARE #Utc DATETIME = '2019-01-01 10:00:00';
DECLARE #UtcOffset datetimeoffset(7) = #Utc;
SELECT
#Utc Utc,
#UtcOffset UtcOffset,
#UtcOffset AT TIME ZONE 'Central European Standard Time' UtcConverted;
-- Results
-- Utc 1/1/2019 10:00:00 AM
-- UtcOffset 1/1/2019 10:00:00 AM +00:00
-- UtcConverted 1/1/2019 11:00:00 AM +01:00
Zohar Peled explained it just fine, but just in case, here is a code example:
DECLARE #timeUTC DATETIME = '2019-01-01 10:00:00';
SELECT
#timeUTC AS timeUTC,
#timeUTC AT TIME ZONE 'Central European Standard Time' as at_time_zone_offset,
CONVERT(datetime, cast (#timeUTC AT TIME ZONE 'Central European Standard Time' as datetimeoffset),1) at_timezone_convert,
CAST(CAST(#timeUTC AS datetimeoffset) AT TIME ZONE 'Central European Standard Time' AS datetime) AS ResultYouNeeded;
This may be the most pathetic question ever asked related to SQL and date/time values, but I could use some help...
Trying to setup a function/job that will run at a specified time or times in eastern, mountain, central, and pacific time zones (in theory other zones would work too). The system will identify which users belong to each timezone and then output data from the system highlighting what they've accomplished for the current day.
Here is my challenge, I know all date/time values are stored on the SQL DB in UTC. I can apply the offset and convert those times to local time zones. Rather than convert tens of thousands of date/time values to local time and make comparisons there, it'd be cleaner (I think) to simply adjust the beginning and ending date/time values of UTC within the stored procedure.
On the west coast it is currently just about 2017-09-30 14:30:00 and in UTC is 2017-09-30 21:30:00, this clearly demonstrates a 7 hour time zone difference right now which means "today" from a user perspective technically started at 2017-09-30 07:00:00 and will end on 2017-10-01 06:59:999 in UTC.
What is the best way of establishing these date/time values for a users beginning of day and ending of day values?
UPDATES
I currently have this code...
DECLARE #InputDate as DateTime
DECLARE #InputEndDate as DateTime
DECLARE #InputDateWithOffset as DateTimeOffSet
DECLARE #InputEndDateWithOffset as DateTimeOffSet
SET #InputDate = '2017-09-28'
SET #InputDateWithOffset = #InputDate AT TIME ZONE 'UTC' AT TIME ZONE 'Pacific Standard Time'
SET #InputEndDate = DATEADD(day, 1, DATEADD(ms, -3, #InputDate))
SET #InputEndDateWithOffset = #InputEndDate AT TIME ZONE 'UTC' AT TIME ZONE 'Pacific Standard Time'
SELECT
#InputDate AS InputDate, #InputEndDate AS InputEndDate,
#InputDateWithOffset AS InputDateWithOffset,
#InputEndDateWithOffset AS InputEndDateWithOffset
Which outputs the following:
The last two columns appear to be correct as it would represent both the beginning of the Input Date and the ending of the Input Date as the Input Date is going to be the local date of the execution...
When I take the #InputDateWithOffset and #InputEndDateWithOffset against my table values with datetimes in UTC, it appears the only dates being returned are those that fall on 2017-09-28 and seems to disregard the comparisons to the Offset date/times.
Your update is mostly correct. However, you're missing a "start of day" operation, which needs to be done in local time.
Consider:
DECLARE #InputStartUTC as DATETIME, #InputEndUTC as DATETIME
DECLARE #InputStartDTO as DATETIMEOFFSET, #InputEndDTO as DATETIMEOFFSET
DECLARE #InputStartDTOatStartOfDay as DATETIMEOFFSET,
#InputEndDTOatStartOfDay as DATETIMEOFFSET
DECLARE #tz as VARCHAR(50) = 'Pacific Standard Time'
SET #InputStartUTC = '2017-09-28 00:00:00'
SET #InputStartDTO = #InputStartUTC AT TIME ZONE 'UTC' AT TIME ZONE #tz
SET #InputStartDTOatStartOfDay = CAST(CAST(#InputStartDTO as DATE) as DATETIME)
AT TIME ZONE #tz
SET #InputEndUTC = DATEADD(day, 1, #InputStartUTC)
SET #InputEndDTO = #InputEndUTC AT TIME ZONE 'UTC' AT TIME ZONE #tz
SET #InputEndDTOatStartOfDay = CAST(CAST(#InputEndDTO as DATE) as DATETIME)
AT TIME ZONE #tz
SELECT
#InputStartUTC as InputStartUTC, #InputEndUTC as InputEndUTC,
#InputStartDTO as InputStartDTO, #InputEndDTO as InputEndDTO,
#InputStartDTOatStartOfDay as InputStartDTOatStartOfDay,
#InputEndDTOatStartOfDay as InputEndDTOatStartOfDay
Also, notice I did not subtract three milliseconds from your end date. Rather than trying to figure out .997 or .999 or whatever, the better approach is to query using a half-open interval. In other words, start <= value AND end > value.