What is the Overall Record when Since Beginning of Big 12 is ou, 27-3?
CREATE TABLE "record_vs_big_12_opponents" (
  "oklahoma_vs" text,
  "overall_record" text,
  "at_norman" text,
  "at_opponent_s_venue" text,
  "at_neutral_site" text,
  "last_5_meetings" text,
  "last_10_meetings" text,
  "current_streak" text,
  "since_beginning_of_big_12" text
);
SELECT "overall_record" FROM "record_vs_big_12_opponents" WHERE "since_beginning_of_big_12"='ou, 27-3';