- From: Martynas Jusevičius <martynas@graphity.org>
- Date: Tue, 12 May 2015 14:33:43 +0200
- To: "Svensson, Lars" <L.Svensson@dnb.de>
- Cc: Kingsley Idehen <kidehen@openlinksw.com>, "public-lod@w3.org" <public-lod@w3.org>
Lars, this is a very simple answer that I have given you before: a shape of RDF data is defined as SPARQL query. There are no two ways about it. Martynas On Tue, May 12, 2015 at 2:18 PM, Svensson, Lars <L.Svensson@dnb.de> wrote: > Kingsley, > > On Monday, May 11, 2015 9:00 PM, Kingsley Idehen wrote: > >> We have to be careful here. RDF Language sentences/statements have a >> defined syntax as per RDF Abstract Syntax i.e., 3-tuples organized in subject, >> predicate, object based structure. RDF Shapes (as far as I know) has nothing to >> do with the subject, predicate, object structural syntax of an RDF >> statement/sentence. Basically, it's supposed to provide a mechanism for >> constraining the entity type (class instances) of RDF statement's subject and >> object, when creating RDF statements/sentences in documents. Think of this as >> having more to do with what's regarded as data-entry validation and control, in >> other RDBMS quarters. > > The charter of the data shapes WG [1] says that "the product of the RDF Data Shapes WG will enable the definition of graph topologies for interface specification, code development, and data verification", so it's not _only_ about validation etc. My understanding is that it's somewhat similar to XML schema and thus is essentially a description of the graph structure. As such, it can of course be used for validation, but that is only one purpose. > >> The function of the "profile" I believe you (and others that support this) are >> seeking has more to do with enabling clients and servers (that don't necessarily >> understand or care about RDF's implicit semantics) exchange hints about the >> nature of RDF document content (e.g., does it conform to Linked Data >> principles re. entity naming [denotation + connotation] ). > > No, my use of "profile" is really a "shape" in the sense of the data shapes wg. Some of their motivations are what I'm envisioning, too, e.g. > > * Developers of each data-consuming application could define the shapes their software needs to find in each feed, in order to work properly, with optional elements it can use to work better. > * Developers of data-providing systems can read the shape definitions (and possibly related RDF Vocabulary definitions) to learn what they need to provide > >> Cut long story short, a "profile" hint is about the nature of the RDF content (in >> regards to entity names and name interpretation), not its shape (which is >> defined by RDF syntax). > > OK, I stand corrected: My question is: How can clients and servers negotiate shape information? > > Best, > > Lars
Received on Tuesday, 12 May 2015 12:34:12 UTC