How many {student} are for {Jacques-Louis David} ?
Give me the number of students Jacques David teaches.
How many students does Jacques-Louis David teach?
SELECT ( COUNT ( ?b ) AS ?w ) { resource:Jacques-Louis_David property:student ?b }
SELECT (COUNT(?obj) AS ?objs ) {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q83155> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P802> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
} 

SELECT (COUNT(?obj) AS ?value ) { wd:Q83155 wdt:P802 ?obj }
25