Import 
In order to import (load) data and/or the database catalog, you can use either Database Studio or Loader.
Caution
You cannot use export data to restore a database because it may not represent a consistent database state in some cases. Importing data is therefore no substitute for restoring the database using data backups.
End of the caution.
More Information
Database Studio, Importing Data and/or Information from the Database Catalog
Loader, Importing: Loader Commands
Database Administration, Exporting and Importing