Either title or author must be supplied, however the title need not be complete - a substring of the title might be supplied. All books that satisfy the search criterion are listed. The purpose of this interaction is to allow a patron to pay a fine. Id and the amount to be paid. The amount is deducted from the patron's fine.
Any excess is considered a donation to the library and the amount of fine remaining is returned.
The purpose of this interaction is to allow a librarian to update the database to record the fact that another day has passed. The interaction fails if the initiator is not a librarian.