Is there a clear separation between user data and Drupal data in the database? Possible Duplicate:
  Deploying content updates from staging server to live server  




I am trying to find a solution to the following scenario:


Let's assume a Drupal site is in production. Users create a lot of content everyday.
In development, additional features (content types and others...) and modules are being added to the site.
Comes the day to move the upgraded site to production.
The upgraded site is out of synch with user data in production.


How does one solves this issue? Is there a clean way to perform this? Should one export 'some' databases tables from current production and import them into the upgraded system? If yes which tables?
You might want to look at the Deploy and UUID modules together.