My first question is how to update the this document. A "sister" document, Wikibase/DataModel/JSON says that the document should not be edited in the normal way, but rather "NOTE: The canonical copy of this document can be found in the Wikibase source code and should be edited there. Changes can be requested by filing a ticket on Phabricator"
Does a similar process apply to this document, or is this document edited directly?
The change I think should be made is as follows, with bold showing material to add:
The full value includes the simple value above under
wikibase:timeValue, precision and timezone as integers and calendar model as IRI. The timezone parameter has never been implemented and should be ignored; all times in the database are local times; that is, the timezone is not recorded as part of the time and must be deduced from other clues, such as the place an event occurred.
I consider this important because editors may be unwilling to contribute to Wikidata if it forces them to make false statements, such as the time zone being UT when it is really United States Eastern Daylight Time.
I will be making a parallel request for revision of Wikibase/DataModel/JSON.
[Text above added September 2016. Text below added 31 December 2016.]
- If a date is given with day precision, one has to ignore all information which make more precise claims including the time zone. The time zone parameter is only needed for dates/times with at least hour precision. So Wikidata doesn't say anything if a date is in UTC or in local time. Basically a specific day is a time period of 50 hours, from 12:00a.m. in UTC+14:00 (Q7130) to 11:59p.m. in UTC−12:00:
While this may have been a defensible interpretation of earlier versions of this document, and maybe even a defensible interpretation of the JSON dump spec, this spec says
- The simple value of the time value is either datetime value of type
xsd:dateTime, if the value can be converted to Gregorian date in ISO format, or a string as represented in the database, if not. The
xsd:dateTimedates follow XSD 1.1 standard...
Considerable effort has recently been expended to respect the XSD standard to always use the Gregorian calendar, by creating code to convert Julian dates to Gregorian dates. If this effort has been put into respect the Gregorian calendar aspect of the XSD spec, I infer the meaning of the "Z" an the end of the representations, which means Universal Time, would be equally respected. Jc3s5h (talk) 15:58, 31 December 2016 (UTC)