CREATE TABLE "past_winners" (
  "year" real,
  "men_s_singles" text,
  "women_s_singles" text,
  "women_s_doubles" text,
  "mixed_doubles" text
);

Question: Who participated in the Mixed Doubles when Tracey Hallam participated in the Women's Singles?
SQL: SELECT "mixed_doubles" FROM "past_winners" WHERE "women_s_singles"='tracey hallam';

Question: Who participated in the Mixed Doubles when Simon Santoso participated in the Men's Singles after 2008?
SQL: SELECT "mixed_doubles" FROM "past_winners" WHERE "men_s_singles"='simon santoso' AND "year">2008;