how many video game distribution systems are supported by xbox?
Value
2
class entity
cvg.computer_game_distribution_system m.02plp2
cvg.computer_game_distribution_system cvg.cvg_platform
Video Game Distribution System xbox
count none
cvg.computer_game_distribution_system.platforms_supported
Platforms supported
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> PREFIX : <http://rdf.freebase.com/ns/> 
SELECT (COUNT(?x0) AS ?value) WHERE {
SELECT DISTINCT ?x0  WHERE { 
?x0 :type.object.type :cvg.computer_game_distribution_system . 
VALUES ?x1 { :m.02plp2 } 
?x0 :cvg.computer_game_distribution_system.platforms_supported ?x1 . 
FILTER ( ?x0 != ?x1  )
}
}
(COUNT (AND cvg.computer_game_distribution_system (JOIN cvg.computer_game_distribution_system.platforms_supported m.02plp2)))