CREATE TABLE affected_region (region_id DECIMAL, storm_id DECIMAL, number_city_affected DECIMAL)
CREATE TABLE region (region_id DECIMAL, region_code TEXT, region_name TEXT)
CREATE TABLE storm (storm_id DECIMAL, name TEXT, dates_active TEXT, max_speed DECIMAL, damage_millions_usd DECIMAL, number_deaths DECIMAL)

How many regions are affected?
SELECT COUNT(DISTINCT region_id) FROM affected_region
SELECT COUNT(DISTINCT "region_id") FROM "affected_region"