When the played number is less than 8 and against is 23, what is the least amount of points?
CREATE TABLE "torneio_rio_s_o_paulo" (
  "position" real,
  "team" text,
  "points" real,
  "played" real,
  "against" real,
  "difference" text
);
SELECT MIN("points") FROM "torneio_rio_s_o_paulo" WHERE "against"=23 AND "played"<8;