Is there a way to search for a resource by its referencing resources? For example, is the a way to find all Observations of code = X with Provenance by agent Y?
GET [base]/Observation?code=X&???
One could:
GET [base]/Provenance?userid=Y&_include=Provenance:target:Observation
but that prevents any kind of filtering on Observation (which may create a volume problem in the response!). Also, I don't need the provenance resource - I just need to make sure that the Observations I'm using have a certain provenance.