title: Database.Designer.cs not taking changes from Designer mode (Entity Framework)
body: <p>I am working on a complex project that does not allow me to do a simple 'update model from database'. I have added a column to a table we have called <code>ContactPhoneNumbers</code> the catch here is that we have over 100 different versions of it all with different schemas for different companies (hence why I can't update my model from the db). I created a script and successfully added the new columd <code>Extension</code> to each table. I am manually trying to add the column in to the .csdl, .msl, and .ssdl files as well as adding them to the designer and designer.cs code behind files. I keep getting an error saying  </p>
  
  <p><strong>The Column 'Extension' specified as part of this MSL does not exist in MetadataWorkspace.</strong>  </p>
  
  <p>I have manually added the column to all required areas of each .xxdl file mentioned above and added it to the code behind file of the designer but each time I hit save the constructor in the designer.cs file erases the manual line I place to set the Extension column  </p>
  
  <p>This   </p>
  
  <pre><code> public static ContactPhoneNumber CreateContactPhoneNumber(global::System.Guid contactPhoneNumberId, global::System.Guid contactId, global::System.String phoneNumber, global::System.String phoneNumberType, global::System.String extension)
      {
          ContactPhoneNumber contactPhoneNumber = new ContactPhoneNumber();
          contactPhoneNumber.ContactPhoneNumberId = contactPhoneNumberId;
          contactPhoneNumber.ContactId = contactId;
          contactPhoneNumber.PhoneNumber = phoneNumber;
          contactPhoneNumber.PhoneNumberType = phoneNumberType;
          contactPhoneNumber.Extension = extension;
          return contactPhoneNumber;
      }  
  </code></pre>
  
  <p>Turns into this</p>
  
  <pre><code>public static ContactPhoneNumber CreateContactPhoneNumber(global::System.Guid contactPhoneNumberId, global::System.Guid contactId, global::System.String phoneNumber, global::System.String phoneNumberType)
      {
          ContactPhoneNumber contactPhoneNumber = new ContactPhoneNumber();
          contactPhoneNumber.ContactPhoneNumberId = contactPhoneNumberId;
          contactPhoneNumber.ContactId = contactId;
          contactPhoneNumber.PhoneNumber = phoneNumber;
          contactPhoneNumber.PhoneNumberType = phoneNumberType;
          return contactPhoneNumber;
      }  
  </code></pre>
  
  <p>I think this is why I am getting this error since I believe the designer file is what takes care of the metadataworkspace. Here is my designer file (which never changes)</p>
  
  <p><img src="https://i.stack.imgur.com/e8viJ.png" alt="enter image description here"> </p>
  
  <p><strong>How can I get my Object Model to match my conceptual, storage, and mapping models manually?</strong></p>