- From: Jan Grant <Jan.Grant@bristol.ac.uk>
- Date: Thu, 3 May 2001 15:39:52 +0100 (BST)
- To: Danny Ayers <danny@panlanka.net>
- cc: Www-Rdf-Logic <www-rdf-logic@w3.org>, RDF-Interest <www-rdf-interest@w3.org>
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 jan * that is, very (what, fifth NF?): for instance, moving one-to-one data into a separate table if the data describes a separate concept; it's generally possible to produce a normalised schema from a less normalised (ie, more real-world) one with the judicious use of views. -- 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 ( echo "ouroboros"; cat ) > /dev/fd/0 # it's like talking to yourself sometimes
Received on Thursday, 3 May 2001 10:41:22 UTC