Re: Relevant documents on SPIN

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.

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.

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?

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

peter


On 10/25/2014 03:42 PM, Holger Knublauch wrote:
>
> On 10/26/14, 8:00 AM, Peter F. Patel-Schneider wrote:
>> I don't think that the SPIN Modelling document answers my questions.
>>
>> SPIN does more than constraint checking.  The details of SPIN as a
>> inferencing system appear to affect its use as a constraint system.
>
> No they don't. And I said this already: spin:rule is unrelated to this topic.
>
>>
>> For example, what happens if the input graph has spin:CV node?
>
> Such nodes would be treated like any other node.
>
>>
>> As far as I can tell, spin:CV nodes are no different from other information.
>> Is this the case?
>
> Yes. Unless when they are created by a CONSTRUCT but I already explained this.
>
> Holger
>
>>
>> I am trying to figure out just how SPIN works, particular as a constraint
>> mechanism, but I'm not finding a complete description, hence my questions.
>>
>> peter
>>
>>
>> On 10/24/2014 08:33 AM, Irene Polikoff wrote:
>>> Peter,
>>>
>>> I believe most of the information you are looking for is available in W3C
>>> SPIN submission document, specifically, this part
>>> http://www.w3.org/Submission/2011/SUBM-spin-modeling-20110222/
>>>
>>> In short, SPARQL queries identified using spin:rule predicate are about
>>> inferring new triples (thus, these are CONSTRUCT, INSERT and DELETE
>>> queries) while those identified using spin:constraint are about checking
>>> constraints (ASK and CONSTRUCT queries).
>>>
>>> For example, when ?width and ?height are available, spin:rule may infer the
>>> value of ?area. In contrast, if ?width ?height and ?area are all available,
>>> a constraint may check if their values are valid - in other words, check if
>>> ?area=?width*?height.
>>>
>>> Regards,
>>>
>>> Irene
>>>
>>>
>>>
>>> -----Original Message-----
>>> From: Peter F. Patel-Schneider [mailto:pfpschneider@gmail.com]
>>> Sent: Friday, October 24, 2014 3:42 AM
>>> To: Holger Knublauch; public-data-shapes-wg@w3.org
>>> Subject: Re: Relevant documents on SPIN
>>>
>>> Thanks Holger, this document does a decent job of outlining SPIN.
>>>
>>> However, there are some unexplained things.  (Maybe these are explained in
>>> other documents but I could not
>>>
>>> Just what signals a constraint violation?  Is it the presence of a node of
>>> type spin:ConstraintViolation (a spin:CV node)?  If so, how can an RDF
>>> graph that contains such nodes be processed? Is it the construction of a
>>> spin:CV node?  If so, what difference is there between spin:constraint and
>>> spin:role?
>>>    Is it the construction of a spin:CV node by a spin:constraint?  If so,
>>> how is this signalled?
>>>
>>> It appears that the computation required for constraint checking in SPIN is
>>> potentially unbounded.  Is that correct?  Where is the description of the
>>> SPIN execution engine?
>>>
>>> Do you have a list of known SPIN implementations?
>>>
>>> peter
>>>
>>> PS:  Let's try to keep the name calling down to close to zero.
>>>
>>>
>>>
>
>

Received on Saturday, 25 October 2014 23:01:47 UTC