- From: McBride, Brian <bwm@hplb.hpl.hp.com>
- Date: Mon, 19 Feb 2001 15:10:40 -0000
- To: "'Sergey Melnik'" <melnik@db.stanford.edu>, RDF Interest Group <www-rdf-interest@w3.org>
Hi Sergey, In the model you describe, it seems that ExExE is a subset of E. Is E a well formed set? 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. > > -- > E-Mail: melnik@db.stanford.edu (Sergey Melnik) > WWW: http://www-db.stanford.edu/~melnik > Tel: OFFICE: 1-650-725-4312 (USA) > Address: Room 438, Gates, Stanford University, CA 94305, USA >
Received on Monday, 19 February 2001 10:10:47 UTC