A project can contain several sites, and siteId records which one a given Artifact came from. This connects the find to its broader site context — the cultural affiliation, eligibility, and location recorded on the site. The link is required, so every artifact is tied to a site. Because the relation uses restrict-on-delete, a site that still has artifacts cannot be deleted out from under them, protecting the provenience chain.
Technical section
Data model, API, and internals — visible to developers.