问题
Hi i am in new to ontologies. I have developed a restaurant ontology by Protege software. But I badly need a SPARQL query that finds property values for all individuals of a class.
I want to get a result like:
Angels_n_Gypsies
House #30, Rd No. 19/A, Dhaka 1213, Bangladesh
回答1:
Just follow the property values...
SELECT ?rname ?lname
WHERE {
?inst a :Popular_restaurant .
?inst :restaurant_name ?rname .
?inst :Location_name ?lname .
}
But that's just the end result. A way to understand SPARQL is to start pedantically. For example:
SELECT ?inst
WHERE {
?inst a :Popular_restaurant .
}
That gets you all members of the class :Popular_restaurant. Then find what properties are defined for each member:
SELECT ?inst ?p ?o
WHERE {
?inst a :Popular_restaurant .
?inst ?p ?o .
}
And the bindings for p
will tell you what properties are defined for members of this class. So use those values to continuously refine the query.
来源:https://stackoverflow.com/questions/36752918/how-to-get-individuals-data-property-value-in-sparql