Oracle datafile 생성 이후 모든 archive log는 있으나 datafile의 backup이 없는 경우 recovery

기본적으로 recovery는 backup된 datafile을 가져다 놓고 backup 시점 이후의 archive log를 적용하게 됩니다. 

complete recovery의 경우 모든 archive log가 적용된후 undo가 다시 적용되는데요..

아래의 시나리오는 backup된 datafile은 없으나, 손상된 datafile 생성 시점이후 모든 archive log가 있을 경우 recovery하는 시나리오입니다. 

예전 data guard에서는 primary DB에서 datafile 생성한게 standby에 생성되지 않아 수작업으로 'alter database create datafile,..'을 수행했던거 같은데, 요즘 version에서는 되는지 모르겠네요..

Re-Creating Datafiles When Backups Are Unavailable: Scenario

If a datafile is damaged and no backup of the file is available, then you can still recover the datafile if:

• All archived log files written after the creation of the original datafile are available

• The control file contains the name of the damaged file (that is, the control file is current, or is a backup taken after the damaged datafile was added to the database)

  Note:

  You cannot re-create any of the datafiles for the SYSTEM tablespace by using the CREATE DATAFILE clause of the ALTER DATABASE statement because the necessary redo is not available.

To re-create a datafile for recovery:

Create a new, empty datafile to replace a damaged datafile that has no corresponding backup. For example, assume that the datafile ?/oradata/trgt/users01.dbf has been damaged, and no backup is available. The following statement re-creates the original datafile (same size) on disk2:

ALTER DATABASE CREATE DATAFILE '?/oradata/trgt/users01.dbf' AS
                               '/disk2/users01.dbf';

손상된 '?/oradata/trgt/users01.dbf'를 '/disk2/users01.dbf'로 이름을 바꿔 빈 datafile을 생성합니다. 

This statement creates an empty file that is the same size as the lost file. The database looks at information in the control file and the data dictionary to obtain size information. The old datafile is renamed as the new datafile.

Perform media recovery on the empty datafile. For example, enter:

RECOVER DATAFILE '/disk2/users01.dbf';

새로 만들어진 빈 datafile에 대해 archive log를 complete로 적용합니다.

All archived logs written after the original datafile was created must be applied to the new, empty version of the lost datafile during recovery.

* 여기저기서 좋다는 책 몇권 추천합니다. 고수가 되는 그날까지.. 파이팅!!