How many more games were sold on game platform ID 50 than on game platform ID 51 in region ID 1?
result = subtract(sum(num_sales where game_platform_id = 50), sum(num_sales where game_platform_id = 51))
SELECT (SUM(CASE WHEN T.game_platform_id = 50 THEN T.num_sales ELSE 0 END) - SUM(CASE WHEN T.game_platform_id = 51 THEN T.num_sales ELSE 0 END)) * 100000 AS nums FROM region_sales AS T WHERE T.region_id = 1
database name:db_id video_games
genre table genre Cols: id dtype integer, genre_name dtype text, 
game table game Cols: id dtype integer, genre id dtype integer, game name dtype text, 
platform table platform Cols: id dtype integer, platform_name dtype text, 
publisher table publisher Cols: id dtype integer, publisher_name dtype text, 
game_publisher table game_publisher Cols: id dtype integer, game id dtype integer, publisher id dtype integer, 
game_platform table game_platform Cols: id dtype integer, game publisher id dtype integer, platform id dtype integer, release year dtype integer, 
region table region Cols: id dtype integer, region_name dtype text, 
region_sales table region_sales Cols: region_id dtype integer, game platform id dtype integer, number sales dtype real, 
