- From: Jan Grant <Jan.Grant@bristol.ac.uk>
- Date: Thu, 3 May 2001 17:08:18 +0100 (BST)
- To: Seth Russell <seth@robustai.net>
- cc: Danny Ayers <danny@panlanka.net>, Www-Rdf-Logic <www-rdf-logic@w3.org>, RDF-Interest <www-rdf-interest@w3.org>
On Thu, 3 May 2001, Seth Russell wrote: > From: "Jan Grant" <Jan.Grant@bristol.ac.uk> > > > On Thu, 3 May 2001, Danny Ayers wrote: > > > > > Has anyone come across a mapping of the relational model to RDF? I'm > sure > > > there's a pretty direct one possible at a low level (tuple to tuple I > > > suppose), but it'll save me some thought and a lot of time if someone's > > > already looked into this. Alternatively, if there's an RDFS around that > > > contains RDBMS terms (schema, table, column etc) I'd very much like to > hear > > > about it. I'm wanting to operate at this latter level, but it would be > nice > > > to be on firm foundations. > > > > I've done quite a bit of thinking about it; got some paper notes which > > I'm in the (slow) process of typing up. You're right, there's a simple > > mechanical mapping of rows in a table to RDF; what you lose by this is > > the natural linking of properties. > > > > For a sufficiently normalised relational schema*, you can generally > > produce a mapping > > (primary key) -> resource > > (other values) -> properties > > (foreign key) -> link to resource representing primary key for > > foreign table > > > > No doubt you are aware of the list of these recorded at [1], to which list I > have added the structure diagrammed at [2]. > > [1] http://www-db.stanford.edu/~melnik/rdf/db.html > [2] http://robustai.net/mentography/SemStructure.gif Neat; but these seem to be "storing RDF in RDBMS" as opposed to "producing RDF from a (legacy?) RDBMS" -- jan grant, ILRT, University of Bristol. http://www.ilrt.bris.ac.uk/ Tel +44(0)117 9287163 Fax +44 (0)117 9287112 RFC822 jan.grant@bris.ac.uk "Sufficiently large"="infinite" for sufficiently large values of "sufficiently"
Received on Thursday, 3 May 2001 12:09:33 UTC