According to a specific implementation manner that a questioning and answering system including a transaction node interacts with a user in the embodiments of the present invention, a quick call to an existing function or service can be realized, and by acquiring modification information for a set system component in the questioning and answering system, and correspondingly updating the questioning and answering system according to the modification information, the existing questioning and answering method based on a questioning and answering system, the existing method for generating the questioning and answering system, and the existing method for modifying the questioning and answering system are optimized, thereby improving efficiency and accuracy of questioning and answering, and improving generation efficiency and modification efficiency of the questioning and answering system.