title: Why spring data jpa not issuing JOIN query?
body: <p>I have created two entities <code>Book</code> and <code>Book_Category</code> with one-to-many relationship. When I issued <code>BookCategoryRepository.findAll()</code>, I expected hibernate to use 'INNER JOIN' query. But it just issued query to take data from Book_Category.</p>
  
  <p>What I am missing?  What should I do to make hibernate issue JOIN query?</p>
  
  <p>Book.java</p>
  
  <pre><code>@Entity
  public  class Book {
  
      @Id
      @GeneratedValue(strategy = GenerationType.AUTO)
      private int id;
      private String name;
  
      @ManyToOne
      @JoinColumn(name = "book_category_id")
      private BookCategory bookCategory;
  }
  </code></pre>
  
  <p>BookCategory.java</p>
  
  <pre><code>@Entity
  @Table(name = "book_category")
  public  class BookCategory {
  
      @Id
      @GeneratedValue(strategy = GenerationType.AUTO)
      private int id;
      private String name;
      @OneToMany(mappedBy = "bookCategory", fetch = FetchType.EAGER, cascade = CascadeType.ALL)
      private Set&lt;Book&gt; books;
  }
  </code></pre>
  
  <p>BookCategoryRepository.java</p>
  
  <pre><code>public  interface BookCategoryRepository extends JpaRepository&lt;BookCategory, Integer&gt; {
  }
  
  
  bookCategoryRepository.findAll()
  </code></pre>