Out of my depth here (no experience) but "Codds relational database model adds the further constraint that nested tables are not allowed" may be wrong. He allowed nested stuff, it's just that SQL didn't support it.
Can anyone elucidate? Please don't shout that I'm wrong because there was something there in his first paper.
Can anyone elucidate? Please don't shout that I'm wrong because there was something there in his first paper.