title: NHibernate - Identity Column
body: <p>I have declareted the fallowing Mapping for NHibernate:</p>
  
  <pre><code>&lt;class name="Sales" table="Sales" lazy="false"  &gt;
      &lt;id name="Id" column="Id" type="Guid"&gt;      
                      &lt;generator class="assigned"/&gt;
      &lt;/id&gt;
    &lt;version name="ObjectVersion" column="ObjectVersion"/&gt;
      &lt;property name="Number" column="Subject" type="String" length="255"  /&gt;
      &lt;property name="Text" column="Body" type="String" length="50" not-null="true"  /&gt;
  &lt;/class&gt;
  </code></pre>
  
  <p>I should now add a additional Column called Key which is defined as an AutoIncrement-Column. Can someone give me a tip how I have to declare this column? This Column has not to be the primary-key - i need only a additional column which has a integer which count up for each record.</p>
  
  <p>Thanks for your help.</p>
  
  <p>Best Regards, Thomas</p>