CREATE TABLE "classification_leadership_by_stage" (
  "stage" real,
  "winner" text,
  "general_classification" text,
  "points_classification" text,
  "mountains_classification" text,
  "intergiro_classification" text,
  "trofeo_fast_team" text
);

Question: what is total number of points where the stage is 17?
SQL: SELECT COUNT("points_classification") FROM "classification_leadership_by_stage" WHERE "stage"=17;