Is there a way in Semantic Mediawiki to store and use relative dates?
I would like to store genealogical data in Semantic Mediawiki and there is sometimes information like: »On January 10th 2021 John, son of the deceased Jack, married Mary.« Now I know that Jack died BEFORE 2021-01-10. Is there any way to store (and query) such information -- BEFORE 2021-01-10 -- in a date property, just like in GEDCOM format?