CREATE TABLE "average_crowd_sizes" (
  "season" text,
  "ave_attendance" real,
  "ave_on_prev_season" text,
  "competition" text,
  "occupier" text
);

Question: How many values of attendance occur when ave. on previous season is +645?
SQL: SELECT COUNT("ave_attendance") FROM "average_crowd_sizes" WHERE "ave_on_prev_season"='+645';

Question: What is the lowest value of average attendance when average on previous season is -459?
SQL: SELECT MIN("ave_attendance") FROM "average_crowd_sizes" WHERE "ave_on_prev_season"='-459';

Question: What is the least value for average attendance when average on previous season is +644?
SQL: SELECT MIN("ave_attendance") FROM "average_crowd_sizes" WHERE "ave_on_prev_season"='+644';

Question: What is every value for average on previous season if the competition is league two?
SQL: SELECT "ave_on_prev_season" FROM "average_crowd_sizes" WHERE "competition"='League Two';