- From: Curt Tilmes <Curt.Tilmes@nasa.gov>
- Date: Wed, 12 Sep 2012 09:27:41 -0400
- To: <public-prov-wg@w3.org>
I see your point -- by design the data model itself should be very general. Could we leave the DM itself open, but constrain the type of prov:type within PROV-O and/or PROV-XML? In translating the examples where they have free text, we can simply impose a namespace to qualify the types in the more concrete representations. Curt On 09/12/2012 09:22 AM, Luc Moreau wrote: > Hi Curt and Stephan, > > I am less certain about this change. > > First, do you mean QName as in xsd:QName? > Why not use the prov:QualifiedName, which we already have (and can be > transformed into uris). > > But then, why just prov:QualifiedName , and why not URI (xsd:anyURI)? > > The reason why this was left unspecified is that PROV, intentionally, > refrained from defining > what a type system is, and therefore, a consequence, was that we didn't > define how to > represent a given type value. > > Luc > > On 09/12/2012 01:27 PM, Curt Tilmes wrote: >> >> I agree with Stephan. The real reason for having prov:type at all is >> to encourage consistency. Qnames encourage capturing semantic meaning >> beyond free text. >> >> The types we've defined >> http://www.w3.org/TR/prov-dm/#term-attribute-type >> set a precedent for the type of types we think should fill prov:type, >> and the discussion of prov:type in the extensibility points section: >> http://www.w3.org/TR/prov-dm/#extensibility-section >> shows examples defining new prov:types as qnames in other namespaces. >> >> This would require some rework of examples, but I think the change >> would be valuable in the long term. >> >> Curt >> >> On 09/12/2012 02:19 AM, Stephan Zednik wrote: >>> A quick reminder about this issue. >>> >>> Looking at the PROV-DM document again I see a few examples where simple >>> non-qname strings are used for prov:type values. >>> >>> From example 21 (http://www.w3.org/TR/prov-dm/#anexample-communication) >>> >>> prov:type="fine paying, check writing, and mailing" >>> >>> I think in most if not all of these cases the prov:type value could be >>> simplified to a qname. >>> >>> I understand this change is significant due to the timing of the >>> suggestion, but I believe the benefit of making this change is >>> worthwhile. >>> >>> Thanks, >>> --Stephan >>> >>> On Sep 4, 2012, at 11:18 AM, Provenance Working Group Issue Tracker >>> <sysbot+tracker@w3.org <mailto:sysbot+tracker@w3.org>> wrote: >>> >>>> PROV-ISSUE-493: prov:type has type Value; valid values too general, >>>> include number, datetime, boolean, etc. [prov-dm] >>>> >>>> http://www.w3.org/2011/prov/track/issues/493 >>>> >>>> Raised by: Stephan Zednik >>>> On product: prov-dm >>>> >>>> The value of prov:type is a Value >>>> (http://www.w3.org/TR/prov-dm/#term-value) which has the following >>>> definition: >>>> >>>> A value ◊ is a constant such as a string, number, time, qualified >>>> name, IRI, and encoded binary data, whose interpretation is outside >>>> the scope of PROV. Values can occur in attribute-value pairs. >>>> >>>> Each kind of such values is called a datatype. Use of the following >>>> data types is recommended. >>>> >>>> The RDF-compatible [RDF-CONCEPTS] types, including those taken from >>>> the set of XML Schema Datatypes [XMLSCHEMA11-2]; >>>> Qualified names introduced in this specification. >>>> The normative definitions of these datatypes are provided by their >>>> respective specifications. >>>> >>>> This means that numbers, datetimes, booleans, and unstructured strings >>>> are valid values of prov:type. The prov value section on RDF >>>> compliance also seems to suggest there should be a prov:type datatype >>>> property in prov-o, which to my knowledge does not currently exist. >>>> >>>> So my question is, are we ok with numbers, datetimes, booleans as >>>> valid values of prov:type? All of the examples in the DM document >>>> appear to use qnames for values of prov:type. >>>> >>>> Second, is there support for a proposal to restrict values of >>>> prov:type to qnames? >>>> >>>> >>>> >>>> >>> >> >> > -- Curt Tilmes, Ph.D. U.S. Global Change Research Program 1717 Pennsylvania Avenue NW, Suite 250 Washington, D.C. 20006, USA +1 202-419-3479 (office) +1 443-987-6228 (cell) globalchange.gov
Received on Wednesday, 12 September 2012 13:28:07 UTC