- From: Bruce D'Arcus <bdarcus@gmail.com>
- Date: Thu, 18 Oct 2007 15:21:27 -0400
- To: Garret Wilson <garret@globalmentor.com>
- CC: Sandro Hawke <sandro@w3.org>, semantic-web@w3.org
Garret Wilson wrote: > Bruce D'Arcus wrote: ... >> Question: are the difficulties around these issues in RDF a >> consequence of the open world assumption, and the need to be able to >> merge statements from disparate graphs? > > No, I don't think that's the core issue here. The issue is simply that > there are many types of relationships in the universe, whether it's open > or closed, that cannot easily be represented by RDF because RDF doesn't > allow properties to be ordered. Needing to order properties without > resorting to heavy list-list classes is a *very* common use-case. Right, but I'm not clear how you merge ordered lists? E.g. the unordered nature of RDF is not some dumb hack, but a design feature. > Let me give a few examples. (The 99% and 1% should be understood as exemplary, > not as actual percentages.) > > * 99% of the people in the world have a single last name, or multiple > last names that can come in any order. 1% of the people have multiple > last names for which order of these names is important. Do we create an > ontology in which the ex:lastName property takes only a single string > value, or do we make every ex:lastName property take an rdf:List, just > so that 1% of the people can represent their names correctly? (Note that > the problem here is not the open world assumption---maybe we know > exactly who those 1% are, and what their names are.) We've argued about this before, but to summarize, I think your way of describing this problem is a function of your programming background and does not reflect real world name usage. I think I'll be content when SPARQL supports reasonable query of lists. [snip] Bruce
Received on Thursday, 18 October 2007 19:21:50 UTC