How many {commanded by} are for {Warsaw Pact} ?
Who are the people commanded Warsaw pact?
How many people commanded for the {Warsaw Pact} ?
SELECT ( COUNT ( ?a ) AS ?h ) { resource:Warsaw_Pact property:commanded_by ?a }
SELECT (COUNT(?obj) AS ?objs ) {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q41644> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P4791> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
} 

SELECT (COUNT(?obj) AS ?value ) { wd:Q41644 wdt:P4791 ?obj }
5