How many {medical condition} are to/by {brain tumor} ?
What number of different medical conditions can contribute to a diagnosis of a brain tumor?
how many medical conditions lead to a brain tumor?
SELECT ( COUNT ( ?o ) AS ?p ) { ?o property:medical_condition resource:brain_neoplasmm }
SELECT (COUNT(?sub) AS ?subs ) {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?sub .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P1050> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> http://wikidata.dbpedia.org/resource/Q233309 .
} 

SELECT (COUNT(?sub) AS ?value ) { ?sub wdt:P1050 wd:Q233309 }
30