What order did Lambert perform in the top 11?
CREATE TABLE "table1_21501511_1" (
  "week_num" text,
  "theme" text,
  "song_choice" text,
  "original_artist" text,
  "order_num" text,
  "result" text
);
SELECT "order_num" FROM "table1_21501511_1" WHERE "week_num"='Top 11';