What is the lowest Decile for a school with a roll smaller than 3?
CREATE TABLE "kaikoura_district" (
  "name" text,
  "years" text,
  "gender" text,
  "area" text,
  "authority" text,
  "decile" real,
  "roll" real
);
SELECT MIN("decile") FROM "kaikoura_district" WHERE "roll"<3;