Re: Provenance in RDF

----- Original Message -----
From: "Dave Reynolds" <der@hplb.hpl.hp.com>
To: "RDF Interest (E-mail)" <www-rdf-interest@w3.org>
Sent: Wednesday, February 27, 2002 7:14 AM
Subject: Provenance in RDF


> We are working on a semantic web related application that needs some
provenance
> support. We have various routes for doing this but would be interested in
> hearing of other's experiences. Are there any groups out there that have
> developed applications supporting provenance within RDF that would be
willing to
> share their experiences on what worked well or badly?
>
[...]
>
> Dave

We put up a site to test this and other issues a while back
(http://www.intellidimension.com/itdsw/default.asp). The source and time is
stored for each statement and statement visibility to queries is controlled
by rules (i.e. if the statement comes from a source you trust, you see it --
{?p ?s ?o} <- {[x:sourceOf] ?source {?p ?s ?o}} and {[x:trusts]
[x:CurrentUser] ?source}.

We started with conventional triple-based reification (1 statement = 4
triples + provenance triples) but moved to a quad representation internally
for performance reasons (1 statement = 1 quad + provenance triples).
Performance was workable with triple reification but much improved with
quads.

Geoff