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Slim RDF

From: Sergey Melnik <melnik@db.stanford.edu>
Date: Mon, 12 Feb 2001 12:08:41 -0800
Message-ID: <3A8842C9.2587CDA@db.stanford.edu>
To: RDF Interest Group <www-rdf-interest@w3.org>
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
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Address:     Room 438, Gates, Stanford University, CA 94305, USA
Received on Monday, 12 February 2001 14:47:52 GMT

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