title: Entity framework Optimistic Concurrency Exception
body: <p>Should I maintain a <code>Timestamp property</code> on my Model classes for enable <strong>optimistic concurrency</strong> for data update and delete ?  If I won't use such a attribute,whether EF will give concurrency exception at run time  or not ?</p>
  
  <p>Is this must for enable the concurrency handling ?</p>
  
  <pre><code>[Timestamp]
  public byte[] RowVersion { get; set; }
  </code></pre>