title: Id of newly added Entity before SaveChanges()
body: <p>I am adding an entity to my database like so:</p>
  
  <pre><code>public TEntity Add(TEntity entity)
  {
       return (TEntity)_database.Set&lt;TEntity&gt;().Add(entity);
  }
  </code></pre>
  
  <p>However, the <code>DbSet.Add</code> method isn't returning the newly added entity with the Id etc, it is simply returning the object I passed in to my <code>Add</code> method.</p>
  
  <p>Should it be passing me back the complete new entity including <code>Id</code>, or is it not possible to get the <code>Id</code> before <code>SaveChanges()</code> is called?</p>