Is there any way to get the current time for particular given time zone?
For EX: GetDateTime("Morocco Standard Time")
It should give the local time of time zone "Morocco Standard Time"
Thanks in Advance,
Merlin
I know that the question is quite old, but maybe the answer will help someone.
If you are using SQL Server 2016 you can use new feature AT TIME ZONE. Let's get to the result that you need step by step.
First, use function SYSDATETIMEOFFSET() to retrieve current date and time in UTC time zone. The return type of this function is DATETIMEOFFSET, which stores not only date, but also related time zone information:
SELECT SYSDATETIMEOFFSET()
-- Result is 2016-08-20 13:15:25.3760873 +03:00
Then this with AT TIME ZONE statement. This returns DATETIMEOFFSET in the time zone that you need:
SELECT SYSDATETIMEOFFSET() AT TIME ZONE 'Morocco Standard Time'
-- Result is 2016-08-20 11:15:25.3760873 +01:00
Additionally if you want to lose time zone information and use DATETIME, you can cast the above result to DATETIME:
SELECT CAST( SYSDATETIMEOFFSET() AT TIME ZONE 'Morocco Standard Time' AS DATETIME)
-- Result is 2016-08-20 11:15:25.376
Related
I have a query like this:
SELECT
to_date(to_char((from_tz(to_timestamp(to_char(my_column, 'YYYY-MM-DD HH:MI:SS PM'), 'YYYY-MM-DD HH:MI:SS PM') ,'America/Edmonton')at time zone 'America/Vancouver'),'YYYY-MM-DD'),'YYYY-MM-DD') as Date_Column
FROM
my_table
It converts the time between MST to PST. This works most of the time except when daylight savings time occurs. Then a situation happens when in the clock moves forward an hour, and then since an hour is lost (for example 1:59 to the 3:00 am) then we are trying to convert a fictional time.
So I am aware of the issue, and I know Oracle will throw this error for that reason:
ORA-01878: specified field not found in datetime or interval
I've looked all over the Internet for a possible work around but can't really find anything that works. I just want to modify my query so that it can tell what time of year it is and either do the conversation when the time exists, or handle the time somehow when it does not exists. Perhaps add the extra hour when it's missing, and remove it when it's the other time of year.
Does anyone have a solution for this? Is this an impossible problem?
Instead of all the conversions you are using, just use AT TIME ZONE. You may need to take extra care depending on the data type of your column. The AT TIME ZONE functionality will always take into account daylights savings time.
If your column is a TIMESTAMP WITH TIME ZONE, that would be ideal
because you could just say AT TIME ZONE 'PST' and you would get the
time in PST.
If the column is the datatype TIMESTAMP, when you use AT TIME ZONE it
will convert from the time zone of the current session to whatever
you specify.
If your column is a DATE, you will need to convert it to a TIMESTAMP first, then you can use the AT TIME ZONE function. Converting the DATE to TIMESTAMP will make the time zone 0:00 offset so be sure to account for that.
Another handy trick is to use AT LOCAL. This will convert the timestamp to the time zone of the current session. This may be handy if you have users of your application that are in multiple time zones.
Example
I am in the time zone -04:00 (East coast US) which is why that appears as my time zone in the examples below.
WITH
my_table
AS
(SELECT TIMESTAMP '2021-01-01 8:00:00 -7:00' AS ts_with_tz,
TIMESTAMP '2021-01-01 8:00:00' AS ts,
DATE '2021-01-01' + (8 / 24) AS dt
FROM DUAL)
SELECT 1 AS example_num,
t.ts_with_tz,
t.ts,
t.dt
FROM my_table t
UNION ALL
SELECT 2 AS example_num,
t.ts_with_tz AT TIME ZONE 'PST',
t.ts AT TIME ZONE 'PST',
TO_TIMESTAMP (t.dt) AT TIME ZONE 'PST'
FROM my_table t
ORDER BY 1;
RESULT
EXAMPLE_NUM TS_WITH_TZ TS DT
______________ ______________________________________________________ ______________________________________________________ ______________________________________________________
1 01-JAN-21 08.00.00.000000000 AM -07:00 01-JAN-21 08.00.00.000000000 AM AMERICA/NEW_YORK 01-JAN-21 08.00.00.000000000 AM AMERICA/NEW_YORK
2 01-JAN-21 07.00.00.000000000 AM AMERICA/LOS_ANGELES 01-JAN-21 05.00.00.000000000 AM AMERICA/LOS_ANGELES 31-DEC-20 09.00.00.000000000 PM AMERICA/LOS_ANGELES
I'm using Oracle Database 12c. I want to know how oracle manages timezone details for DATE datatype.
If i were to migrate data between time zones can i still get away with using DATE datatype? Or do i have to use TimeStamp or TimeStamp with TimeZone?
Does it keep the UTC time in DB and convert it when querying for results according to session time zone or some other NLS setting?
Thank you.
No, data type DATE does not handle any time zone information. Use data type TIMESTAMP WITH TIME ZONE or TIMESTAMP WITH LOCAL TIME ZONE
TIMESTAMP WITH TIME ZONE holds date + time + time zone
TIMESTAMP WITH LOCAL TIME ZONE holds date + time and these are stored internally in DBTIMEZONE (typically UTC). The value is always shown in the current user session time zone SESSIONTIMEZONE.
If you like to convert a DATE to TIMESTAMP WITH {LOCAL} TIME ZONE, then you must tell Oracle which time zone shall be used.
Typically you do it like this:
FROM_TZ(CAST({date_value} AS TIMESTAMP), 'desired time zone')
The cast is required because FROM_TZ requires a TIMESTAMP rather than a DATE
If you don't specify the time zone, e.g. like CAST({date_value} AS TIMESTAMP WITH TIME ZONE) then Oracle defaults the time zone to SESSIONTIMEZONE
What is the best way to always get the right time in Europe/Paris (including summer/winter times) ?
So far, I'm using the following query :
select FROM_TZ(CAST(Sysdate AS TIMESTAMP), 'Europe/Paris') from dual
It was working nicely in a previous server. However, we have changed our database server and now we are getting a difference of one hour.
Is there any way to get always the correct time in Paris ?
Thanks.
SYSDATE is returned in the time zone of database server's operating system. When you run FROM_TZ(CAST(Sysdate AS TIMESTAMP), 'Europe/Paris') then you "attach" time zone Europe/Paris to SYSDATE.
So, FROM_TZ(CAST(Sysdate AS TIMESTAMP), 'Europe/Paris') is only correct if the time zone of database server's operating system is Europe/Paris.
Try SYSTIMESTAMP AT TIME ZONE 'Europe/Paris' then result is always correct because SYSTIMESTAMP returns a TIMESTAMP WITH TIME ZONE value and time zones are properly converted.
Will using the following query to retrieve the UTC timestamp from an oracle database cause an issue? I do not want to alter the database timezone parameter in order to retrieve the correct date. I do not want to do alter database set time_zone.
My query at the moment is:
select from_tz(CAST (sys_extract_utc(systimestamp) AS TIMESTAMP), '+00:00') from dual;
I would like to know if this query will result in the correct UTC date in all circumstances regardless of the EST/EDT status.
I don't see anything wrong with your query. Note that if you want to work in UTC for your session, you could simply:
ALTER SESSION SET TIME_ZONE = '0:00';
select CURRENT_TIMESTAMP from dual;
output
11/1/2016 5:48:55.115282 PM +00:00
That would change your current_timestamp (and localtimestamp) for your entire session.
Your query is just setting timezone but not converting time. If that's what you were looking for it is ok. Is local time is 3AM you will return 3AM UTC.
I think you're looking for that query:
select cast(sysdate as timestamp) at time zone 'UTC' from dual;
And the apply
select from_tz(cast(systimestamp at time zone 'UTC' as timestamp), '+0:00') from dual;
Some general notes:
SYSTIMESTAMP and SYSDATE are given in time zone of your database server's operating system. Thus changing database time zone (i.e. DBTIMEZONE) does not change anything.
CAST (sys_extract_utc(systimestamp) AS TIMESTAMP), resp. cast(systimestamp at time zone 'UTC' as timestamp) have a problem. You convert your timestamp to UTC but by CAST(... AS TIMESTAMP) you remove any time zone information from that value. If you like to do any further conversion (e.g. again to TIMESTAMP WITH TIME ZONE value) then your input UTC value is considered to be a SESSIONTIMEZONE value.
from_tz(CAST (sys_extract_utc(systimestamp) AS TIMESTAMP), '+00:00') does following:
Get current time in time zone of your database server's operating system, include time zone information.
Convert this time to UTC, cut time zone information
Append time zone information (+00:00) to this value
Correct output but redundant conversion
cast(sysdate as timestamp) at time zone 'UTC' does following:
Get current time in time zone of your database server's operating system, without any time zone information.
Cast to TIMESTAMP (basically no effect at all)
Consider this value as time in your local session time zone (SESSIONTIMEZONE) and convert to UTC.
Correct output only if time zone of your database server's operating system is the same as your local session time zone, otherwise you get wrong result.
from_tz(cast(systimestamp at time zone 'UTC' as timestamp), '+0:00') does following:
Get current time in time zone of your database server's operating system, include time zone information.
Convert this time to UTC
Cut time zone information
Append time zone information (+00:00) to this value
Correct output but redundant conversion
from_tz(cast(systimestamp as timestamp), '+0:00') does following:
Get current time in time zone of your database server's operating system, include time zone information.
Cut time zone information
Append time zone information (+00:00) to this value
Correct output only if time zone of your database server's operating system is UTC.
I am trying to convert a date field 'createdate' to UTC time but the ask is to be -04:00. I have tried a bunch of things and have had no success. I am working on Oracle. Any ideas? Thank you.
This should do it:
cast(createdate as timestamp with time zone) at time zone 'UTC'
This converts the createdate to a timestamp with your current time zone (the one that is defined by your client through SESSIONTIMEZONE). It then converts that to UTC.
It is not possible if you have a DATE or TIMESTAMP value, because those data types do not have any time zone information and thus it is not possible to convert to any other time zone - unless you treat the value as "local time zone".
There are several solutions:
createdate at time zone 'UTC'
SYS_EXTRACT_UTC(createdate)
FROM_TZ(createdate, 'UTC')
The result types are different, e.g. FROM_TZ returns as TIMESTAMP WITH TIME ZONE values, whereas SYS_EXTRACT_UTC returns a TIMESTAMP value.