Recovering a NOARCHIVELOG Database with Incremental Backups
Restoring a database running in NOARCHIVELOG mode is similar to restoring a 
database in ARCHIVELOGmode.
非归档方式利备份恢复数据库 和归档模式下使用备份恢复数据有些相似的地方
The main differences are:
■ Only consistent backups can be used in restoring a database in NOARCHIVELOG
mode.
■ Media recovery is not possible because no archived redo logs exist.
You can perform limited recovery of changes to a database running in NOARCHIVELOG
mode by applying incremental backups. The incremental backups must be consistent, 
like all backups of a database run in NOARCHIVELOGmode, so you cannot make 
backups of the database when it is open.
When you are recovering a NOARCHIVELOGdatabase, specify the NOREDOoption on 
the RECOVERcommand to indicate that RMAN should not attempt to apply archived 
redo logs. Otherwise, RMAN returns an error.
他们的不同在于：
在非归档模式下只有一致备份才能用来恢复
因为为非归档所以不能进行介质恢复
下面为步骤
To recover a NOARCHIVELOG database with incremental backups:
1. After connecting to the target databaseand the recovery catalog, place the 
database in a mounted state:
STARTUP FORCE MOUNT
2. Restore and recover the database.
For example, you can perform incomplete recovery with the following commands:
RESTORE DATABASE 
FROM TAG "consistent_whole_backup";
RECOVER DATABASE NOREDO;
3. Open the database with the RESETLOGSoption.
For example, enter the following command:
ALTER DATABASE OPEN RESETLOGS