Derived From

Set by a producer on each materialized result instance: a reference to the stable input resource the instance was derived from. This is what keeps a reshaping view's result a set of REFERENCES rather than copies — the row carries the projected/aggregated values, and `derivedFrom` points back at the authoritative source so a consumer can resolve it for anything the projection didn't carry. Domain is rdfs.Resource so it attaches to any produces class without that class having to declare it.