How write this SPARQL request? - sparql

Question

I've the following Ontology built in Protege 4.
In this Ontology : The main class Frame has an datatypeProperty hasDuration with domain 'Frame' and range UnsignedShort. the ClassShortFrame and LongFrame are inferred from the class SizedFrame with the followiing restriction
Rectriction for ShortFrame class
SizedFrame that hasDuration some unsignedLong[<=20]
Rectriction for LongFrame class
SizedFrame that hasDuration some unsignedLong[>=200]
I've manually created an instance of the class frame named frame0, which has a property hasDuration set to 12.
What is the SPARQL query that I need to get the all shortFrame. I hope that frame0 will be inferred like a shortFrame ?
Thanks for any reply !
Edition: sample query
PREFIX frame: <http://www.semantic.org/sample.owl#>
SELECT ?y WHERE {?y rdf:type frame:Frame}
but It is not working ! maybe It is not correct !

Answer 1

I believe, You're going to write some queries for OWL restriction information in SPARQL language. SPARQL is a RDF query language and has no understanding the concepts of OWL. Instead of making a restriction, you can use a data property to define duration value and from that you can get all the shortFrames using SPARQL. Other option I would recommend is use SWRL rules instead of SPARQL. Hope this helps !!

Answer 2

The query you give asks for all instance of type frame:Frame. Since you want just the short frames, you should adapt it like so:
SELECT ?y WHERE {?y a frame:ShortFrame}
...but the above will only work if the reasoner understands your restriction and can correctly classify frame0 as an instance of ShortFrame. I am not overly familiar with Protege's syntax for owl restrictions, so I am not 100% sure your restriction expresses what you want it to express.
As an alternative, you can actually express the restriction you require in SPARQL. To query for all frames with a duration of less than 20:
SELECT ?y
WHERE {
?y a frame:Frame;
frame:hasDuration ?d .
FILTER (?d <= 20)
}