What is the Established date of the Ontario Provincial Junior A Hockey League with more than 1 Championship?
CREATE TABLE "amateur_and_junior_clubs" (
  "club" text,
  "league" text,
  "venue" text,
  "established" real,
  "championships" real
);
SELECT COUNT("established") FROM "amateur_and_junior_clubs" WHERE "league"='ontario provincial junior a hockey' AND "championships">1;