Re: Hierarchical Model and its Relevance in the Relational Model

Hi Derek,

Ok. You put quite a few things on the table that I would like to respond to, but I promised my girl-friend to help with cooking our favourite dish, Dutch-Finnish pea soup, and although I do not consider many things more important then database theory, this is one of them.

So a very quick response on a few points:

1. You don't need my permission to discuss one of my papers here, but if you would like my explicit permission, then you have it now. I would btw. be very curious to know what conclusions your client would think he or she could draw from them.
2. An important point of disagreement between us seems to be what is and what is not part of The Relational Model or how a certain group of people or individuals interpreted it in the past. To be honest, although I have opinions on these issues, I find such discussions unscientific and without any merit, even if it is about how Codd himself meant his model to be understood. It is akin to the argument by authority, which is a very weak type of argument. What matters is, which objective arguments were put forward to support that interpretation and what the evidence for its merit was. Which interpretation leads to the most effective DBMSs and what scientific evidence is there for this. I'd prefer it if we could focus on that in future exchanges.
3. I'm not a mathematician, so would like to ask you to not refer to me in that way. I use math in my research. I have real mathematicians as my coauthors. But I do not hold a PhD or MSc in mathematics, so cannot really make that claim.

Kind regards,

• Jan Hidders