What is the lowest population total in La Romana when the area is less than 1,788.4, the density is greater than 234.77, and a rank greater than 30
CREATE TABLE "by_area" (
  "rank" real,
  "province" text,
  "population" real,
  "area" real,
  "density" real
);
SELECT MIN("population") FROM "by_area" WHERE "area"<'1,788.4' AND "density">234.77 AND "province"='la romana' AND "rank">30;