SELECT MIN(population) FROM table_name_37 WHERE altitude__mslm_ < 197 AND city = "alessandria" AND density__inhabitants_km_2__ < 461.8
Berapa populasi terendah Alessandria di mana ketinggian kurang dari 197 dan kepadatan kurang dari 461.8?
CREATE TABLE table_name_37 (population INTEGER, density__inhabitants_km_2__ VARCHAR, altitude__mslm_ VARCHAR, city VARCHAR)