I have the following task to achieve. My client needs to move part of their database to a new data center. There is no proprietary good network between two centers which are 1,000 miles apart, and downtime can be allowed only for few hours. I wanted to prepare backup level 0 from site A, send it over to site B , restore there, and at the switchover hours, send differential backups over network to site B and apply it by recovering on site B. I know I can do it with full database. The problem is it is too big and client needs just 3 tablespaces to be moved from site A to B, around 70G of data. What is the right solution?