- From: Andy Seaborne <andy.seaborne@epimorphics.com>
- Date: Sun, 27 Feb 2011 22:02:43 +0000
- To: RDF Working Group <public-rdf-wg@w3.org>
On 23/02/11 22:38, Nathan wrote: > Hi Pat, > > All I can say is that I believe you've hit on the distinction we can > make between a Named Graph and a Graph Literal. > > Where a Named Graph correlates to a "Graph Token" as you term it, a > container for triples which can be given a name and accessed, the > contents of the container may change over time, but the container > remains the same, with the same name. > > Where Graph Literal is an abstract graph, a set of triples, that which > is given by a named graph when poked. > > The "value" of a "named graph" at time t is a "graph literal". > > That "value" can be serialized in to a lexical form and passed in a > representation (rdfa, rdf/xml json/rdf, a representation etc), held in > memory or in a quad store or whatever. FWIW: SPARQL 1.1 Update defines a graph store: http://www.w3.org/TR/sparql11-update/#def_graphstore """ A GraphStore GS is a mutable container of RDF graphs. It has one unnamed (default) slot and zero or more named slots identified by an IRI <i>. Each slot holds an RDF graph. """ This is an attempt to allow graph-as-value (immutable) and capture change due to operations. The contents of a slot (named or the unnamed slot) can change value. "RDF graph" is used to mean the abstract value (?? "RDF Abstract graph"), not any representation of the value. It was a conscious choice to have udpates affect a graph store, rather than an "RDF dataset", which is the thing that query acts over. "RDF dataset" SPARQL 1.0: http://www.w3.org/TR/rdf-sparql-query/#defn_RDFDataset """ An RDF dataset is a set: { G, (<u1>, G1), (<u2>, G2), . . . (<un>, Gn) } where G and each Gi are graphs, and each <ui> is an IRI. Each <ui> is distinct. """ so it's not a mutable container. Andy
Received on Sunday, 27 February 2011 22:03:23 UTC