Re: Relevant documents on SPIN

On 10/26/14, 9:01 AM, Peter F. Patel-Schneider wrote:
> Somehow I seem to be missing something about SPIN.  The documents that 
> I see, e.g., http://spinrdf.org/spinsquare.html, say that constraints 
> are similar to rules, with only minor changes. However, when I ask 
> further questions, the answers don't seem to match up with that 
> description.

spin:rule and spin:constraint share a similar syntax.

> Suppose, for example, a spin:rule created a spin:ConstraintViolation 
> node. Would this signal a constraint violation?  If not, just what is 
> required for there to be a constraint violation.
I already explained this several times. spin:rule is independent from 
constraint checking. I also already explained how the constraint 
checking algorithm works.

> Suppose, for example, that a spin:constraint or a spin:rule had a 
> query that mentioned spin:ConstraintViolation?  Would this constraint 
> or rule ever be triggered?  Would it ever be triggered by a constraint 
> violation?

People can write anything in the WHERE clause, but this query goes 
against the domain graph, not the graph of temporarily CONSTRUCTed 
constraint violations.

> Somewhere there should be a document that answers these sorts of 
> questions.

It will hopefully be clarified in a future W3C standard. In the meantime 
I can try to answer your questions here.

Holger

Received on Saturday, 25 October 2014 23:10:31 UTC