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

Question: Which winner has a points classification of Tony Rominger at stage 17?
SQL: SELECT "winner" FROM "classification_leadership_by_stage" WHERE "points_classification"='tony rominger' AND "stage"='17';

Question: Which stage has a mountains classification of Mariano Piccoli, a points classification of Mario Cipollini and was won by Laudelino Cubino?
SQL: SELECT "stage" FROM "classification_leadership_by_stage" WHERE "mountains_classification"='mariano piccoli' AND "points_classification"='mario cipollini' AND "winner"='laudelino cubino';

Question: Who won stage 16?
SQL: SELECT "winner" FROM "classification_leadership_by_stage" WHERE "stage"='16';

Question: Which mountains classification has a general classification of Tony Rominger and was won by Maurizio Fondriest?
SQL: SELECT "mountains_classification" FROM "classification_leadership_by_stage" WHERE "general_classification"='tony rominger' AND "winner"='maurizio fondriest';

Question: What is the general classification at stage 18 that has a points classification of Tony Rominger?
SQL: SELECT "general_classification" FROM "classification_leadership_by_stage" WHERE "points_classification"='tony rominger' AND "stage"='18';

Question: Which stage has a mountains classification of Mariano Piccoli and was won by Giuseppe Citterio?
SQL: SELECT "stage" FROM "classification_leadership_by_stage" WHERE "mountains_classification"='mariano piccoli' AND "winner"='giuseppe citterio';