How many {discoverer or inventor} are for {Sagittarius A} ?
Sagisttarius  A provided how many inventions?
How many inventions were fone by Sagittarius A ?
SELECT ( COUNT ( ?d ) AS ?t ) { resource:Sagittarius_A* property:discoverer_or_inventor ?d }
SELECT (COUNT(?obj) AS ?objs ) {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q237284> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P61> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
} 

SELECT (COUNT(?obj) AS ?value ) { wd:Q237284 wdt:P61 ?obj }
2