Principle and design of database P113 No. 2013211466

Source: Internet
Author: User

14.

Select question number:

4.4.4.3.2

15.

(1) Readers and books: one-to-many; but what about books and readers?

Bibliography and reader: one to one;

Bibliography and books: one on one.

(2) Borrowing also records (reader ID, book ID, loan time, should also time, return time);

Reservation registration (reader ID, appointment time, appointment period, book ID).

(3)

Primary key FOREIGN key

Reader Reader ID

Bibliography ISBN

Book book ID or ISBN none

Borrowing also records book ID reader ID

Register Reader id+ book ID book ID, reader ID

Database principles and Design P113 number 2013211466

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