who is the winner when the home team is sioux falls storm and the year is earlier than 2012?
CREATE TABLE "year_by_year" (
  "year" real,
  "home_team" text,
  "away_team" text,
  "winner" text,
  "score" text
);
SELECT "winner" FROM "year_by_year" WHERE "home_team"='sioux falls storm' AND "year"<2012;