- From: Melvin Carvalho <melvincarvalho@gmail.com>
- Date: Thu, 20 Dec 2012 15:17:33 +0100
- To: David Booth <david@dbooth.org>
- Cc: semantic-web <semantic-web@w3.org>
- Message-ID: <CAKaEYhKCes_9TR0L=W_F3NYtBiWa38gTodmkfSSojWdOMx-zbg@mail.gmail.com>
On 12 December 2012 18:01, David Booth <david@dbooth.org> wrote: > I'm writing a paper to propose a profile of RDF that would enable > simpler tools to process RDF, and I'm wondering if others have > suggestions of constraints that may be helpful to include. The idea is > not to change the RDF standard, but to define a useful, voluntary subset > -- Well Behaved RDF -- that is sufficient for most RDF applications but > simplifies their development. > > For example, one key limitation would be in the use of blank nodes, > which severely complicate what could otherwise be simple tasks, such as > comparing two RDF graphs for equality. With unrestricted blank nodes, > this becomes a difficult graph isomorphism problem instead of a simple > text comparison. Some have suggested eliminating blank nodes entirely, > but a more modest restriction would be to limit them to common idioms > that do not cause such complexity problems: > > A Well-Behaved RDF graph is an RDF graph that can be serialized > as Turtle without the use of explicit blank node identifiers. > I.e., only blank nodes that are implicitly created by the > bracket "[ ... ]" or list "( ... )" notations are permitted. > > Are there other restrictions that would be helpful to have in a Well > Behaved RDF profile, which would simplify our lives as RDF developers, > but still meet the needs of most RDF applications? For example, what if > anything might be said about non-lean RDF graphs? Should typed literals > be required to be well formed per their type semantics? Should the use > of rdf:first and rdf:rest be limited to well-formed, rdf:nil-terminated > lists, i.e., those that can be serialized as Turtle lists “( . . . )”? > Etc. What do others think? > I hope this is not considered too off-topic, but it was actually some passages in literature that helped convinced me of the need for blank nodes. https://soundcloud.com/user2324628/joseph-campbell-on-joyce Particularly the part that says, 'All we experience are predicates ... we attribute subjects to them' > > > -- > David Booth, Ph.D. > http://dbooth.org/ > > Opinions expressed herein are those of the author and do not necessarily > reflect those of his employer. > > >
Received on Thursday, 20 December 2012 14:18:04 UTC