The first is the physical collection of books, including book number, title, author, price, category, call number, publishing house, publication date, collection place and so on.

There is also an entity set for readers. The attributes of the entity set include books, book numbers, titles, categories, publishers, publication dates, authors' names and the number of books that can be borrowed.

Books and materials include text information and picture information, which can be read by anyone without hierarchy. Knowledge documents are professional text and graphic materials, which have certain research value.