Learn Java for Web Development

CHAPTER 1: Introducing Java Web Development 21

The sole purpose of the BookAuthor table is to provide a many-to-many relationship between Book
and Author.

Figure 1-13. Many-to-many relationship between Book and Author

Note As shown in Figure 1-13, there is a one-to-many relationship between Book and BookAuthor,

and there is a one-to-many relationship between Author and BookAuthor. In fact, the sole purpose of the

BookAuthor table is to provide a many-to-many relationship between Book and Author—in other words, an

author can write many books, and a book can have many authors.

Because of the profusion of web applications across several domains, many relational and
nonrelational databases such as NoSQL^12 have emerged. In this book, I’ll use MySQL^13 because
it is the most widely used free database management system (DBMS). To install MySQL, go to
http://dev.mysql.com/downloads/ and click Download. You can download MySQL Server 5.5 or
newer. You can see the instructions for installing MySQL at
http://dev.mysql.com/doc/refman/5.5/en/installing.html.

To create the books database, use the following command:

create database books;

You need to instruct MySQL to create tables in the books database by using the following command:

use books;

Now you can create the tables using the statements illustrated in Listing 1-3.

Listing 1-3. Creating Tables for the Bookstore

CREATE TABLE CATEGORY (
ID INT NOT NULL AUTO_INCREMENT ,
CATEGORY_DESCRIPTION VARCHAR(20) NOT NULL ,
PRIMARY KEY (ID)
);

(^12) http://nosql-database.org/
(^13) http://www.mysql.com/