How many different weeks are there in order number 4 that were judge's choice?
CREATE TABLE "performances" (
  "week_num" text,
  "theme" text,
  "song_choice" text,
  "original_artist" text,
  "order_num" text,
  "result" text
);
SELECT COUNT("week_num") FROM "performances" WHERE "theme"='Judge''s Choice' AND "order_num"='4';