CREATE TABLE table_name_45 (platform_s_ VARCHAR2, year VARCHAR2, director VARCHAR2)

What platform was used for the game directed by Bryan Walker after 2006?
SELECT platform_s_ FROM table_name_45 WHERE year > 2006 AND director = "bryan walker"
SELECT "platform_s_" FROM "table_name_45" WHERE "bryan walker" = "director" AND "year" > 2006