CREATE TABLE "references" (
  "urban_area_locality" text,
  "population" real,
  "land_area_hectares" real,
  "density_inh_km" real,
  "code" real
);

Question: How many codes have a density of 621.68, and a Land area (hectares) larger than 75.28?
SQL: SELECT SUM("code") FROM "references" WHERE "density_inh_km"=621.68 AND "land_area_hectares">75.28;

Question: What is the average density with a land area of 123.02, and a Code larger than 2356?
SQL: SELECT AVG("density_inh_km") FROM "references" WHERE "land_area_hectares"=123.02 AND "code">2356;

Question: What is the average land area with a density of 815.48, and a Population larger than 411?
SQL: SELECT AVG("land_area_hectares") FROM "references" WHERE "density_inh_km"=815.48 AND "population">411;