- From: Sergey Melnik <melnik@db.stanford.edu>
- Date: Mon, 19 Feb 2001 14:51:02 -0800
- To: "McBride, Brian" <bwm@hplb.hpl.hp.com>
- CC: RDF Interest Group <www-rdf-interest@w3.org>
"McBride, Brian" wrote: > > Hi Sergey, > > In the model you describe, it seems that ExExE is a subset of E. > Is E a well formed set? It is, this can be proven formally. Sergey > Brian > > > -----Original Message----- > > From: Sergey Melnik [mailto:melnik@db.stanford.edu] > > Sent: 12 February 2001 20:09 > > To: RDF Interest Group > > Subject: Slim RDF > > > > > > Following the recent discussion on wrt syntax and namespaces > > I'd like to > > mention the internal data model based on RDF that I'm using in my > > research: > > > > Let U be the Unicode alphabet and U* the set of strings > > defined over U. > > The set of entities E and the set of statements V are defined > > using the > > following recursive definition: > > > > 1. U*xU* is subset of E (any tuple consisting of two strings is an > > entity; the first string of the tuple is called namespace of > > the entity, > > the second string is referred to as name of the entity) > > > > 2. ExExE is subset of V (every tuple of three entities constitutes a > > statement) > > > > 3. V is subset of E (every statement is an entity) > > > > A subset of V is called "model". Without reification, E=U*xU* > > and V=E^3. > > > > The set of literals L is defined as L = {"urn:rdf:literal"} x U* (i.e. > > literals are resources and can be used as subjects of > > statements). Other > > primitive data types are handled similarly, e.g. > > ("urn:rdf:literal","5") > > != ("urn:rdf:integer","5"). > > > > Notice that namespaces are first-class citizens. Resource ("xyz","") > > 'reifies' namespace "xyz", so that statements about primitive classes > > like the class of literals are possible. > > > > The above data model subsumes the RDF model defined in M&S 1.0. > > > > Sergey > > > > P.S.: since Oct 2000, RDF API > > (http://www-db.stanford.edu/~melnik/rdf/api.html) supports > > namespaces as > > part of the model, so that both parser and serializer included in the > > API can handle resources like > > ("http://www.w3.org/1999/XMLSchema","date") correctly.
Received on Monday, 19 February 2001 17:45:38 UTC