I know this sounds like a very stupid question, but I've been trying to figure this out and I can't find anything on this, though it seems obvious that this should be doable.
I'm developing something that queries an OWL file through its API using the Manchester OWL Syntax and a HermiT reasoner. I alternatively also run queries on the DL Query tab in Protege 4 to check my query results on that file. The file is basically the Friend Of A Friend (FOAF) ontology with added data instances.
The problem: I can't find a way to query an instance by its unique identifier.
It's supposed to be the URI so e.g. for a Person object with URI http://xmlns.com/foaf/0.1/Andrew_Kuchling
, I tried to run the following queries:
Person and URI value "http://xmlns.com/foaf/0.1/Andrew_Kuchling"
Person value "http://xmlns.com/foaf/0.1/Andrew_Kuchling"
Person and URI value "Andrew_Kuchling"
Person that "Andrew_Kuchling"
none of these work. (The URI is constructed by prefixing http://xmlns.com/foaf/0.1/
to whatever string you enter and URI is not actually identified in the ontology as a property).
In FOAF, mbox_sha1sum
is the sha1sum of a mailbox. Mailboxes are uniquely connected to individuals. So I tried the following query:
Person and mbox_sha1sum value "mbox_sha1sum-property-value-here"
However, it doesn't even execute this query because it feels the query is incorrect. The mbox_sha1sum
value is the same that I've added for this Person. It exists in Individuals.
It does execute this query:
Person and firstName value "Andrew"
All data properties are not specialised data types. Treated as literals by default.
I really don't know what I'm doing wrong. Can someone please please help?