On 29/09/12 17:42, Mark Fischer wrote:
Perhaps my issue here arises from my not quite understanding how validation
works.
In my mind, I had this simplified to: "Here are a bunch of triplets... do
they make sense?"
The reasoning engine then says: "I can't be sure, I'll have to add a bunch
more (via inference) to
be sure I'm seeing the entire picture."
After inferencing, the engine now looks at an expanded store of triples and
decides if they
make sense.
I wanted to skip the middle step.
It all comes down to what validation you want to do.
The built-in validation attempts to check for logical contradictions
that arise due to errors in the ontology (for an example that two
resources can be deduced to be both sameAs and differentFrom each
other). Those contradictions typically don't exist in the base data but
are the result of inference.
In the provided rule sets then *some* of the required inference is
backward chaining. So for those cases it's not "I'll add a bunch of
stuff and hope it's useful" but "I've been asked this validation
question, is there a way of answering it from the data using my rules".
There are other validation tools which ask different questions and don't
use the inference machinery such as Eyeball:
http://jena.apache.org/documentation/tools/eyeball-getting-started.html
A lot of useful validation can also be done by suitably constructed
SPARQL ASK queries.
Dave
