How many episodes aired on october 27, 2008
CREATE TABLE "weekly_ratings" (
  "num" real,
  "episode" text,
  "air_date" text,
  "timeslot" text,
  "viewers" text,
  "weekly_rank_for_living" text
);
SELECT COUNT("episode") FROM "weekly_ratings" WHERE "air_date"='October 27, 2008';