CREATE TABLE "classification_leadership" (
  "stage" text,
  "general_classification" text,
  "points_classification" text,
  "mountains_classification" text,
  "young_rider_classification" text
);

Question: What is the general classification with a 13 stage?
SQL: SELECT "general_classification" FROM "classification_leadership" WHERE "stage"='13';

Question: What is teh stage with Daniele Bennati as the points classification and Giovanni VIsconti as the general classification?
SQL: SELECT "stage" FROM "classification_leadership" WHERE "points_classification"='daniele bennati' AND "general_classification"='giovanni visconti';

Question: What is the general classification of the stage 3 with Daniele Bennati as the points classification and Morris Possoni as the young rider classification.
SQL: SELECT "general_classification" FROM "classification_leadership" WHERE "points_classification"='daniele bennati' AND "young_rider_classification"='morris possoni' AND "stage"='3';

Question: What is the general classification with riccardo riccò as the young rider classification?
SQL: SELECT "general_classification" FROM "classification_leadership" WHERE "young_rider_classification"='riccardo riccò';

Question: What is the point classification with chris anker sørensen as the young rider classification and Christian vande velde as the general classification?
SQL: SELECT "points_classification" FROM "classification_leadership" WHERE "young_rider_classification"='chris anker sørensen' AND "general_classification"='christian vande velde';

Question: What is the point classification of stage 15?
SQL: SELECT "points_classification" FROM "classification_leadership" WHERE "stage"='15';