What is the date of the tournament at Hokkaidō with prize of ￥150000000?
CREATE TABLE "tournament_results" (
  "dates" text,
  "tournament" text,
  "location" text,
  "prize_fund" real,
  "winner" text,
  "owgr_pts" real
);
SELECT "dates" FROM "tournament_results" WHERE "location"='Hokkaidō' AND "prize_fund"=150000000;