Scripted import routines make this job easy. The basic idea is to identify all tables which hold user data. For each of those tables:
1. import all data
2. update any serial number fields
3. do any other data transformation
4. do you need to do another round of imports to bring in the modification date and timestamps?
In addition you may want to think about scripting an automated report to run on the live system before import and again after import to report on the # of records in each table and the highest serial # in each table.
After the import is done you need to compare the two to make sure that:
- all records have been imported
- the serial # is higher than the old serial number
You may also want to consider RefreshFM : www.goya.com.au/refreshfm It's a tool we built ourselves for exactly this purpose. I can build an updater that does all of th things mentioned above in a couple of minutes.