title: Can IF-Match be used to conditionally update a property, not ETAG?
body: <p>In Azure Table, can I use the IF-Match tag when Merging to conditionally update a value on something other than ETAG?</p>
  
  <p>Specifically, suppose I have an object like this</p>
  
  <pre><code>public class Person : TableServiceEntity
  {
  public string Name {get;set;}
  public string Age {get;set}
  
  public DateTime LockDate {get;set;}
  
  }
  </code></pre>
  
  <p>Suppose I want to merge or update the object conditionally on the presence or comparison of the "lock date" value.  Is this possible in Azure?</p>