Types of problem that can occur during Media Recovery

Media recovery encounters a problem while recovering a database backup. There are some problems occur during media recovery.

1) Missing ArchivedLog:
In this database cannot find the archived log recorded in the control file so it stops the recovery.

2) When you attempt to open the database, error ORA-01113 Indicates that a datafile needs media recovery:
- You are performing incomplete recovery but failed to restore all needed datafile backups. 
- Incomplete recovery stopped before datafiles reached a consistent SCN. 
- You are recovering datafiles from an online backup, but not enough redo was applied to make the datafiles consistent. 
- You are performing recovery with a backup control file, and did not specify the location of a needed online redo log. 
- A datafile is undergoing media recovery when you attempt to open the database. 
- Datafiles needing recovery were not brought online before executing RECOVER DATABASE, and so were not recovered.

 3) Corrupted archived logs:
Logs may be corrupted while they are stored on or copied between storage systems. If DB_BLOCK_CHECKSUM is enabled, then the database usually signals checksum errors. If checksumming is not on, then log corruption may appear as a problem with redo.

4) Redo record problems:
- In this, stuck recovery problem occur because of failed consistency checks thats why it stops recovery.
- The database signals an internal error when applying the redo. This problem can be caused by an Oracle bug. If checksums are not being used, it can also be caused by corruptions to the redo or data blocks.

5) Corrupted data blocks:
A datafile backup may have contained a corrupted data block, or the data block may become corrupted either during recovery or when it was copied to the backup. If checksums are being used, then the database signals a checksum error. Otherwise, the problem may also appear as a redo corruption.

6) Random problems:

Memory corruptions and other transient problems can occur during recovery.

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