Re: OO foundation

Stefan Nobis wrote:

> "H. S. Lahman" <hsl_at_pathfindermda.com> writes:

>>First, I think it is important to clarify that the 'relational' in
>>the mismatch isn't referring to the fact that the OO paradigm uses
>>something other than set theory's relational model. The nature of
>>the impedance mismatch lies in the way the OO and RDB paradigms
>>implement the same relational model.

> Huh? I know of the lambda calculus as a foundation of functional
> languages and the relation model as foundation of RDBs. But I wonder
> what the formal foundations of the OO family of languages is
> (references, please).

1. The prog lang (Simula) came first, not the formalisms. Which then inspired +/- aligned with other notions (ADTs etc) that were present/emerging in the CS community at that time.
2. The closest basic formalism that OO could be mapped to is ADTs. ADT theory uses a number of formalisms (algebraic specification, type theories etc) to define the behaviour of ADTs.

But these formalisms use the same 'language' (propositional/predicate logic, set theory etc) as the Relational model.

> As far as I understand those matters I would say the relational model > is more abstract than the OO model

The ADT formalisms suggest otherwise.

> (only the most common language use for the relational model, SQL, is... improvable).

Indeed.

Regards,
Steven Perryman Received on Wed Mar 05 2008 - 10:21:23 CET