title: NHibernate generates INSERT and UPDATE for new entity
body: <p>I have an entity with Id column generated using Hilo.
  I have a transaction, creating a new entity and calling SaveOrUpdate() in order to get the Hilo generated Id of the entity (I need to write that Id to another DB).</p>
  
  <p>later on, within the same transaction I update the new entity, just a simple update of a simple property, and in the end I call SaveOrUpdate() again.</p>
  
  <p>I see that the SQL commands generated are first INSERT and then an UPDATE, but what I want is just an INSERT with the final details of the entity. is that possible? am I doing something wrong?</p>
  
  <p><strong>EDIT: added code sample</strong></p>
  
  <p>here's a very simplified example of pseudo code:</p>
  
  <pre><code>Person newPerson = new Person(); // Person is a mapped entity
  newPerson.Name = "foo";
  _session.SaveOrUpdate(newPerson); // generates INSERT statement
  
  newPerson.BirthDate = DateTime.Now;
  _session.SaveOrUpdate(newPerson); // generates UPDATE statement
  
  // assume session transaction was opened before and disposed correctly for sake of simplicity
  _session.Transaction.Commit();
  </code></pre>