How many {lakes on river} are to/by {Lake Urmia} ?
Can you tell me the amount of lakes are rivers attached to Lake Urmia?
How many rivers and lakes are connected to Lake Urmia?
SELECT ( COUNT ( ?g ) AS ?c ) { ?g property:lakes_on_river resource:Lake_Urmia }
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/P469> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> http://wikidata.dbpedia.org/resource/Q199551 .
} 

SELECT (COUNT(?sub) AS ?value ) { ?sub wdt:P469 wd:Q199551 }
3