What is {population} of {Katowice} that is {point in time} is {2017-6-30} ?
What was the population size in Katowice on June 30, 2017?
On June 30th, 2017, what was the population of Katowice?
SELECT ?u WHERE { ?a property:point_in_time ?a . ?a property:population ?u . FILTER ( CONTAINS ( YEAR ( ?a ) , '2017' ) ) . resource:Katowice property:population ?a }
select distinct ?obj  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q588> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P1082> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
?statement <http://www.wikidata.org/entity/P585> <2017-6-30>
} 

SELECT ?obj WHERE { wd:Q588 p:P1082 ?s . ?s ps:P1082 ?obj . ?s pq:P585 ?x filter(contains(YEAR(?x),'2017')) }