Re: An object-oriented network DBMS from relational DBMS point of view

On Mar 20, 10:33 am, "Alfredo Novoa" <alfred..._at_gmail.com> wrote:
> On 19 mar, 21:21, "Daniel" <danielapar..._at_gmail.com> wrote:
>
> > If
> > you don't have some basic familiarity with that literature and its
> > terminology, it's difficult to have a meaningful discussion.
>
> I don't have a lot of respect for that literature and I am more
> familiar with literature that uses better terminology.
>
> ADT is a rather silly synonym of type. I can not imagine a non
> abstract type nor a type that is not a data type.

So it's going to be difficult to have a meaningful discussion :-)
>
>
> Indeed, it is not meaningful to talk about manufacturing values.
> Values are abstract entities, you can not touch them with your hands
> nor with machinery.

>From Benjamin Pierce's book "Types and Programming Languages",
depending on the underlying calculus for the type system, values can include "numeric and boolean constants, strings, tuples of values, records of values, lists of values, etc."
>
> > Do you think it is meaningful to talk about storing a value in a
> > location in computer memory?
>
> It is meaningful to talk about storing a representation of a value in
> a location in computer memory.

I've quickly skimmed through a couple of books on type theory, including Pierce's, and note that the authors' do not use the expression "representation of a value", rather they use "value". I believe this is standard.
>
> First we should define what an "instance" is.
>
As I replied elsewhere, you can read "data structure" for "instance", if you find that to be clearer. In Java, a data structure conforming to a type definition (e.g. Point), typically encapsulating some state and permitting access to that state through methods, according to the definition of the type. This is a value, a value which is an instance of a type.

Regards,
Daniel Parker Received on Tue Mar 20 2007 - 16:33:22 CET