Re: PROV comments from Clark&Parsia

On Tue, Jan 15, 2013 at 5:56 PM, James Cheney <jcheney@inf.ed.ac.uk> wrote:

> >
> >>
> >> Does this help?  In any case, as noted below, we're happy to revisit
> >> the terminology - to me, though, "uniqueness inferences" does not
> >> sound right.
> >
> > Having said all this, I must also say this is a rather minor point. We
> > don't have any objections if you would like to keep using the term
> > "uniqueness constraints" but then adding a paragraph clarifying this
> > point would be good.
>
>
> Hi,
>
> Yes, we are only debating nomenclature here; of course I agree that one
> can view a functional dependency/uniqueness constraint as an inference
> whose conclusion is an equality formula.  I just wanted to explain my
> rationale for grouping the different kinds of formulas into "inferences"
> and "constraints".  From a formal point of view, they could all be called
> formulas or they could all be called constraints.
>
> I am happy with your proposed resolution of keeping things as is and
> clarifying the point (i.e. explaining that the names "constraint" and
> "inference" are semi-arbitrary and may or may not map to what seems natural
> in other settings).
>
> I wanted to respond to Hector's comments in detail because some of
> Hector's examples gave me the impression that there was some confusion
> about how existential variables behave, which in turn may mean that there
> is something that needs to be further clarified in the document.  I will
> respond separately.  Thanks again for your detailed comments.
>

These existential variables are labelled nulls (in DB nomenclature), right?
If so, I understand how they work, my point is that this should be made
clear to avoid confusion :).


>
> --James
> --
> The University of Edinburgh is a charitable body, registered in
> Scotland, with registration number SC005336.
>
>


-- 
Best,
Héctor