I hope you don’t mind that I as beginner keep asking questions here.
The recording relationship has the attribute “cover”, and the documentation says “Indicates that one entity is a cover of another entity”. But what is a cover in this context? There is no definition.
As I understand it, if a song is first published by an artist by making a recording of it, then all later recordings by other artists are cover recordings, while later recordings by the same artist are not. Is that correct?
But what about songs which where first published by the creator in books or other media, before any recordings was made? Are all recordings of these covers recording, or all but the first, or none?
If a songwriter writes a song to another artist who records it first, and the songwriter then later also records it, is that also a cover recording even though it is made by songwriter?