Table: canadian_championship_players
Columns: year
player
position
nationality
team

Question: What's the nationality of Montreal Impact with Justin Mapp Category:articles with hcards as the player?
SQL: SELECT "nationality" FROM canadian_championship_players WHERE "team" = 'montreal impact' AND "player" = 'justin mapp category:articles with hcards'

Question: After 2009, who was the player that has a nationality of Canada?
SQL: SELECT "player" FROM canadian_championship_players WHERE "nationality" = 'canada' AND "year" > 2009

Question: After 2009, what's the nationality of a player named Dwayne de Rosario Category:articles with hcards?
SQL: SELECT "nationality" FROM canadian_championship_players WHERE "year" > 2009 AND "player" = 'dwayne de rosario category:articles with hcards'

Question: What's the position when the player was Justin Mapp Category:articles with hcards with a United States nationality?
SQL: SELECT "position" FROM canadian_championship_players WHERE "nationality" = 'united states' AND "player" = 'justin mapp category:articles with hcards'