title: Alter uniqueidentifier primary key to be ROWGUIDCOL in SQL Compact 4
body: <p>I'm trying to alter an existing SQL Compact 4 database to change the primary keys to be ROWGUIDCOL, and not succeeding.</p>
  
  <p>The <a href="http://msdn.microsoft.com/en-us/library/ms174123%28v=sql.105%29.aspx" rel="nofollow">SQL Compact ALTER TABLE documentation</a> indicates you can use the ROWGUIDCOL. However, every variant of an ALTER TABLE that I issue fails:</p>
  
  <ul>
  <li><code>ALTER TABLE Company ALTER COLUMN CompanyId UNIQUEIDENTIFIER ROWGUIDCOL NOT NULL</code>: Fails for invalid token: ROWGUIDCOL</li>
  <li><code>ALTER TABLE Company ALTER COLUMN CompanyId ADD ROWGUIDCOL</code> (SQL Server syntax): Fails for invalid token: ADD</li>
  <li><code>ALTER TABLE Company ALTER COLUMN CompanyId UNIQUEIDENTIFIER NOT NULL ROWGUIDCOL</code>: Fails for invalid token: ROWGUIDCOL</li>
  <li><code>ALTER TABLE Company ALTER COLUMN CompanyId ROWGUIDCOL UNIQUEIDENTIFIER NOT NULL</code>: Fails for invalid token: ROWGUIDCOL</li>
  </ul>
  
  <p>From the documentation, the first command should have all the tokens in the proper order.</p>
  
  <p>How do I set ROWGUIDCOL for an existing column in SQL Server Compact 4?</p>