HOW MANY TIMES WAS LUDACRIS THE INTERVIEW SUBJECT FOR THE 20 QUESTIONS COLUMN?
CREATE TABLE "2006" (
  "date" text,
  "cover_model" text,
  "centerfold_model" text,
  "interview_subject" text,
  "20_questions" text,
  "pictorials" text
);
SELECT COUNT("20_questions") FROM "2006" WHERE "interview_subject"='Ludacris';