Smalyshev added a comment. @mkroetzsch I don't think it is specified anywhere, it's just what people do. See https://en.wikipedia.org/wiki/Marissa_Stott and its wikidata item, and another one above. If you just look for items with date 0 in RDF, I'm sure many of them are exactly that. I don't like it but that's what we have in the data, so we need to decide what to do with it.
OTOH, while I agree we should eventually be RDF 1.1 compatible, it does not mean we're obliged to represent all dates in the DB as xsd:dateTime, and I think we are allowed to tweak xsd:dateTime interpretation somewhat. And we don't want to get wrong query results. For now, until we figured out the whole "how dates are represented internally" thing, I think we should take this road for simple values (deep values always have original string): 1. AD dates go to xsd:dateTime, if there's an invalid date like February 31, we make it last day of February that year, and so on. That would allow us to range-search it. 2. Year 0 is invalid date for now, until we decide what to do with it. 3. Negative years are translated into xsd:dateTime as is, i.e. year -1 in data is year -1 in RDF's xsd:dateTime The last one may be dangerous if the loading tool goes after RDF 1.1 as 1 BCE in the data is rendered as -0001. So we can in theory dump it as -0000 but then most RDF tools wouldn't load negative dates correctly. No idea currently what to do with this. TASK DETAIL https://phabricator.wikimedia.org/T94064 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: Smalyshev Cc: Lydia_Pintscher, Denny, Manybubbles, daniel, mkroetzsch, Smalyshev, JanZerebecki, Aklapper, jkroll, Wikidata-bugs, Jdouglas, aude, GWicke _______________________________________________ Wikidata-bugs mailing list [email protected] https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs
