Which On demand has a pay and a Provider of virgin media (formerly ntl:telewest)?
CREATE TABLE "current_providers" (
  "provider" text,
  "years" text,
  "free_or_pay" text,
  "transmission" text,
  "on_demand" text
);
SELECT "on_demand" FROM "current_providers" WHERE "free_or_pay"='pay' AND "provider"='virgin media (formerly ntl:telewest)';