Table: santiago_communes
Columns: commune
area_km_2
2002_population
pop_density_km_2
municipality_website

Question: What are the population densities of all communes with an are of 28.3 sq.km.?
SQL: SELECT "pop_density_km_2" FROM santiago_communes WHERE "area_km_2" = '28.3'

Question: What commune has an area of 12.4 sq.km.?
SQL: SELECT "commune" FROM santiago_communes WHERE "area_km_2" = '12.4'

Question: What commune had a 2002 population of 130394?
SQL: SELECT "commune" FROM santiago_communes WHERE "2002_population" = 130394