thiemowmde added a comment. 1. The timestamp is stored in the **calendar model** indicated by the URI and not converted to Gregorian. This decision was made in May 2013 and finally realized in the UI in 2014. The tragedy is: Most edits in Wikidata are done via the API and we can't say if a Julian date is correct by looking at the time it was entered. It could be that it was entered incorrectly before the switch and is correct now. On the other hand there are bots and scripts out there that still incorrectly convert Julian dates to Gregorian. This can only be fixed gradually by telling all bot and script developers and by re-checking all Julian dates. 2. The timestamp is not **ISO** compliant. This was not the intention. The intention was to have a commonly understood, both human- and machine-readable YMD-ordered format that's independent from the language. We will avoid the word "ISO" in the future. I already started submitting patches for that (see https://gerrit.wikimedia.org/r/#/c/190257/). 3. Gregorian and Julian dates use the same **format**. This allows to reuse the same formatters, parsers and validators. This must change in the future when we introduce other calendar models. 4. The year is **padded** to have between 1 and 16 digits. There is no further guarantee. Even my suggested minimum of 4 digits (see https://github.com/DataValues/Time/pull/33) does not change that because it does not touch existing dates in the database. 5. Month and day being **zero** indicate that they are unknown/undefined/not set. This makes it possible to roundtrip timestamps like "2015-00-00". Users can copy-paste this and the parser will correctly detect "2015" with the precision set to "1 year". The alternative is to store "2015-01-01", which will be incorrectly detected as "1 January 2015" with a precision of "1 day". The disadvantage of storing "2015-00-00" is that it's not ISO compliant and can confuse external parsers, e.g. PHP's parser will convert this to "2014-11-30". Both disadvantages are not relevant. Relying solely on PHP's parser is not possible anyway because it can not deal with, for example, 5-digit years.
TASK DETAIL https://phabricator.wikimedia.org/T88438 REPLY HANDLER ACTIONS Reply to comment or attach files, or !close, !claim, !unsubscribe or !assign <username>. EMAIL PREFERENCES https://phabricator.wikimedia.org/settings/panel/emailpreferences/ To: thiemowmde Cc: Tobi_WMDE_SW, gerritbot, Jc3s5h, JulesWinnfield-hu, thiemowmde, daniel, Aklapper, Lydia_Pintscher, Wikidata-bugs, Jdouglas, aude _______________________________________________ Wikidata-bugs mailing list [email protected] https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs
