title: @ManyToMany(mappedBy = "foo")
body: <p>Foo has:</p>
  
  <pre><code>@ManyToMany(mappedBy = "foos")
  private Set&lt;Bar&gt; bars
  </code></pre>
  
  <p>and Bar has :</p>
  
  <pre><code>@ManyToMany
  private Set&lt;Foo&gt; foos
  </code></pre>
  
  <p>What difference does the location of mappedBy attribute make to a bi-directional relationship , other than whether table is called foo_bar, or bar_foo; and without the mappedBy attribute I get two join tables, both foo_bar and bar_foo.</p>