What is the smallest number of people to attend a game with an H/A of h and the opponent was Roma?
CREATE TABLE "knockout_phase" (
  "date" text,
  "round" text,
  "opponents" text,
  "h_a" text,
  "result_f_a" text,
  "attendance" real
);
SELECT MIN("attendance") FROM "knockout_phase" WHERE "h_a"='h' AND "opponents"='roma';