Write REST APIs using Java and Spring to

1. add a book
2. add one or more categories to a book and
3. find books using isbn or author or title

Here are the tables and their fields:

1. Book

-- id: int

-- isbn: string

-- title: string

-- author: string

-- year_published: timestamp

2. Category

-- id: int

-- name: string

-- description: string

3. Book_Category

-- book_id: int

-- category_id: int

You can use postgres, mysql or any other sql database of your choice. If you have any questions please do not hesitate to ask. Please document any assumptions you make.

BONUS:

If there were 10 million entries in the book table, how would your code perform? what would you do differently to ensure it performs well?