Migrate Database domains

When you migrate From WPS 6.0 to WPS 6.1, the migration process does not migrate all the database domains. Instead it migrates only RELEASE and COMMUNITY database and the customization database is reused as it is. The JCR database is copied, the copy is different from exporting data from one database and importing it into another, it is raw copy.

This is the diagram that i copied from "WebSphere Portal v6.1 Migration" web cast that indicates what happens when you migrate.