Re: Blank Nodes Re: Toward easier RDF: a proposal

On 11/29/18 6:12 PM, Hugh Glaser wrote:
 >> David Booth wrote:
 >> In my own experience, objects composed of literal attributes
 >> like this generally *do* form a composite key, though
 >> perhaps other RDF developers have had different experience.
 >
 > Since you ask :-)
 > I'm sorry to report that my experience is that they often don't.

Fair enough.  I guess it depends a lot on the data origins.

 > . . .  So it would be folly to try to automagically generate URIs
 > for such bNodes in general - generated unique URIs or sufficiently
 > large random ones is the best that you can do.

Agreed.  But I think my point still holds if a (composite) key
can be conveniently indicated.

 > I think that if you consider *all* the properties, essentially
 > the SCBD, you might get away with it, almost always.
 > (As someone else pointed out.)

I think that would be too risky to rely on.

 > . . . postal address
 > gets more difficult.  For a start, it is very unusual from
 > disparate datasets to get such well and uniformly formatted
 > addresses.  . . .

Agreed.  Data cleaning and normalizing issues will always exist.
But I think that's kind of a separate issue.  We cannot expect
to automagically clean up people's dirty data.  But we *can*
give users better support for collapsing duplicate nodes if
they follow good practices such as indicating keys -- provided
that we devise a *convenient* notation for them to do so.

 > And you need to decide what to do about missing fields.

Missing key fields would prevent a standardized URI from
being generated.  Missing non-key fields would have no impact.

David Booth

Received on Friday, 30 November 2018 02:29:35 UTC