title: spring boot: Cannot delete or update a parent row: a foreign key constraint fails
body: <p>I have the following class:</p>
  <pre><code>@EmbeddedId
  private BookAuthorId id;
  
  @ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
  @MapsId(&quot;bookIsbn&quot;)
  private Book book;
  
  @ManyToOne(fetch = FetchType.LAZY)
  @MapsId(&quot;authorId&quot;)
  private Author author;
  
  @NotNull(message = &quot;Author's index can not be null&quot;)
  @Column(name = &quot;author_index&quot;)
  private Integer index;
  </code></pre>
  <p>}</p>
  <p>So, basically, I try to delete a book without any author and it works, when I have some authors with a book I get:
  java.sql.SQLIntegrityConstraintViolationException: Cannot delete or update a parent row: a foreign key constraint fails (<code>books</code>.<code>books_authors</code>, CONSTRAINT <code>FKg92282id84r9l5youm7y12vpg</code> FOREIGN KEY (<code>book_isbn</code>) REFERENCES <code>books</code> (<code>isbn</code>))</p>
  <p>Some ideas?</p>
  <p>Ty</p>