CREATE TABLE "pre_season_and_friendlies" (
  "date" text,
  "opponents" text,
  "h_a" text,
  "result_f_a" text,
  "attendance" real
);

Question: What's the attendance when the opponents are cambridge united?
SQL: SELECT "attendance" FROM "pre_season_and_friendlies" WHERE "opponents"='cambridge united';

Question: What's the average attendance when the opponents are dundalk?
SQL: SELECT AVG("attendance") FROM "pre_season_and_friendlies" WHERE "opponents"='dundalk';

Question: What's the total attendance for H/A of A and opponents of wolverhampton wanderers?
SQL: SELECT COUNT("attendance") FROM "pre_season_and_friendlies" WHERE "h_a"='a' AND "opponents"='wolverhampton wanderers';