Name the total number of district for population may being 478
CREATE TABLE "barangays_districts" (
  "barangay" text,
  "district" text,
  "population_may_1_2000" real,
  "population_august_1_2007" real,
  "population_may_1_2010" text
);
SELECT COUNT("district") FROM "barangays_districts" WHERE "population_may_1_2010"='478';