Hi!
I've made a lot of good use of Wikidata for
harvesting information about
names in our database, including specific birth & death dates. But, when
a specific date isn't known, & only a year is known, WD records that as
January 1 of that year. I have to throw away any date that is January 1,
as I can't be sure if it is accurate. I know there is a (rather awkward)
way of recording "circa" for dates, but is there some identifier for an
unknown date within the year of ____ that can be used?
Well, in Wikidata itself there is a precision accompanying the date - if
the precision is "years", then you know you can discard the day.
In SPARQL database, the short time value[1] does not carry precision, so
unfortunately there's no way to know from that value, but if you use
full wikibase:Time value, again, you can use wikibase:timePrecision to
know if the date is accurate or just a placeholder.
[1]
https://www.mediawiki.org/wiki/Wikibase/Indexing/RDF_Dump_Format#Time
--
Stas Malyshev
smalyshev(a)wikimedia.org