In SQL Server I would like to create a table to save time of an event, and would like to convert it into the timezone of the users choice for display purposes. Let us say that If there was an event that happens in London at 1:00 PM GMT, that would be 8:00 am US EST.
Given This example I would like to create a frame work,
where a user would have an ability to save the event and time (Giving the time zone of the event)
Read Those events, with the time displayed in the time zone of his liking (US EST)
How do I accomplish this in SQL Server.
In SQL Server 2008, use the DATETIMEOFFSET data type which is a DATETIME plus a timezone offset included.
SELECT CAST('2010-11-23 16:35:29+09:00' AS datetimeoffset)
would be Nov 23, 2010, 4:35pm in a +9 hour (from GMT) timezone.
SQL Server 2008 also contains functions and SQL commands to convert DATETIMEOFFSET values from one timezone to another:
SELECT
SWITCHOFFSET(CAST('2010-11-23 16:35:29+09:00' AS datetimeoffset), '+01:00')
would result in:
2010-11-23 08:35:29.0000000 +01:00
Same time, different timezone (+1 hour from GMT)
When you save the data, save the GMT, not the local time for the user (in c# this is DateTime.UtcNow)
In your application logic, record the user's timezone, and translate the GMT time to the user's local time using the timezone offset, at runtime.
The way I've solved a similar problem is to do the following:
The table design is to only store GMT time.
All input goes through a stored proc that requires an input of a timezone offset.
The data request is to a Table-Valued Function, with an input for the timezone offset.
Related
I added my schedules in apscheduler(MySQL Database) in UTC time format but now I need to migrate all my schedules to a different time zone like CST or any other time zone inside the database so that they trigger with the modified timezone and not in UTC.
Code snippet:
scheduler_obj.add_job(schedule_request, "cron",id=str(job_obj.request_id),
year="*",month="*",day="*",week="*",day_of_week="*",hour="*", minute="*/5",
second="0", start_date="2018-01-01 03:00:00", end_date="2019-01-01 03:00:00",
misfire_grace_time=15,timezone=ltz)
The Best approach here?
I am working with CDC in sql and we have a table lsn_timeMapping and a column inside this table trans_begintime its type as mentioned in sql is datetime. My question is how can i get to know that whether it stores datetime in utc format or server datetime .
HERE is a flow mentioned in msdn
It would appear that the time is stored based upon the server's locale settings(local timezone). Therefore, it will not be UTC unless the server timezone is set to UTC.
Source: https://connect.microsoft.com/SQLServer/feedback/details/533689/store-utc-in-lsn-time-mapping
I am having an issue while using GetDate(), for some reason is not returning the right time (it is 7 hours ahead from the actual time) I am using AZURE and the Database is configured with the right location (West US). I will appreciate any help!
I tried to run this script:
SELECT id,
status,
AcceptedDate,
Getdate(),
Datediff(hour, AcceptedDate, Getdate())
FROM orderoffers
WHERE status = 'Accepted'
Azure SQL Databases are always UTC, regardless of the data center. You'll want to handle time zone conversion at your application.
In this scenario, since you want to compare "now" to a data column, make sure AcceptedDate is also stored in UTC.
Reference
The SQL databases on the Azure cloud are pegged against Greenwich Mean Time(GMT) or Coordinated Universal Time(UTC) however many applications are using DateTime.Now which is the time according to the regional settings specified on the host machine.
Sometimes this is not an issue when the DateTime is not used for any time spanning or comparisons and instead for display only. However if you migrate an existing Database to SQL Azure using the dates populated via GETDATE() or DateTime.Now you will have an offset, in your case it’s 7 hours during Daylight Saving Time or 8 hours during Standard Time.
I created a simple function that returns the correct UK time whether in DST or not.
It can be adapted for other time zones where DST kicks in.
CREATE FUNCTION [dbo].[f_CurrentDateTime]() RETURNS DATETIME AS
BEGIN
RETURN DATEADD(HOUR,CONVERT(INT,(SELECT is_currently_dst FROM sys.time_zone_info WHERE 1=1 AND NAME = 'GMT Standard Time')),GETDATE())
END
In this modern times where infrastructure is scaled globally, it is good idea to save data in UTC and convert to a timezone based on users location preference.
Please refere: https://learn.microsoft.com/en-us/dotnet/api/system.datetime.utcnow?view=netframework-4.7.2
I need to convert the time from GMT format to AEST (Australia) and also take care of the daylight saving properly.
Any idea or help will be appreciated.
Thanks
Shadab
MySQL provides a CONVERT_TZ function. For this to work, the time_zone% tables have to be populated.
There's no need for me to repeat the MySQL documentation.
http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_convert-tz
In SQL Server 2008 and newer, you can use the DATETIMEOFFSET datatype for date/time values including a time zone.
There's also a TODATETIMEOFFSET function that converts a UTC time to a timezone-based date/time.
So in your case, you could convert the UTC date/time to AEST date/time like this:
DECLARE #todaysDateTime datetime2;
SET #todaysDateTime = SYSUTCDATETIME();
SELECT
TODATETIMEOFFSET (#todaysDateTime, '+10:00'); -- AEST date/time
What I don't really know is whether there's anything to automagically handle daylight savings settings - you might need to handle that yourself, by defining the timezone offset (+10:00 for AEST, +11:00 for AEDT, depending on the date in the year).
........
Where
(microsdb.MENU_ITEM_DETAIL.CheckDetailID = microsdb.CHECK_DETAIL.CheckDetailID Or
microsdb.DISCOUNT_DETAIL.CheckDetailID = microsdb.CHECK_DETAIL.CheckDetailID) And
microsdb.CHECKS.CheckOpen = CONVERT(CHAR(23), CURRENT_TIMESTAMP, 25)
**Return no result.
Field Data Type
microsdb.CHECKS.CheckOpen (datetime, not null)
CheckOpen 2013-04-08 06:29:26.000
I wondered why my CheckOpen time always 8 hours early than my server time.
Please advise.
Thanks
More than likely, when you stored data into the CheckOpen column of your CHECKS table you parsed it (or read it) directly from a client machine or client interface using their time-zone of US/Pacific.
Later, when you read CURRENT_TIME from your DB server you got the system time for that machine in UTC (since the machine was setup to use UTC by your server admin).
So, the two times are 8 hours off. UTC (GMT) is 8 hours ahead of US/Pacific.
Generally, if a client machine gives you data, you need to parse it, validate it, and sometimes translate it to valid server values or be aware when it's stored that it's only a "client" value. For date/time values, either convert to UTC or be sure to store the "offset" with the stored time. (actually it can be good to store offset even after converting to UTC)