RMAN 12c DUPLICATE enhancements
When you duplicate a database using RMAN DUPLICATE, the database is created and opened with RESETLOGS mode.
In 12c :
With Oracle database 12c, you can specify that the database must not be opened with “NOOPEN”
Situation for NOOPEN:
•If you need to make changes to initialization parameters after the duplication
•Opening the database conflict with other source database in the same server
•If you plan to create database for upgrade and want to open in upgrade mode
The command below creates duplicate database, but it will not open.
RMAN> DUPLICATE TARGET DATABASE TO DB1 FROM ACTIVE DATABASE NOOPEN;