You can also use Enterprise Manager (EM) to create a duplicate (clone) database. From the EM home page, navigate to Data Movement > Clone database. The screenshot displays the Clone Database: Source Type page.
You can choose from the following venues for the clone operation:
Running instance: You can specify a running instance to be cloned.
Staging area: A disk area specified on the source and destination hosts. A backup is created and stored here, then put in the destination staging area, and read from on that destination host to create the clone database.
Existing backup: If you already have a backup that reflects the database in the state you want it cloned, you can use that.