401st questions, 053401

401st questions, 053401

401. Which of the following are correct about block media recovery? (Choose all that apply .)

A. Physical and logical block upload uption is recorded automatically in V $ DATABASE_BLOCK _
Upload uption.
B. Logical uptions are repairable by BMR.
C. Physical uptions are repairable by BMR.
D. RMAN can use any backup for a BMR restore.
E. ARCHIVELOG mode is not required if you have both a full and incremental backup for restore.
Answer:AC

In most cases, the database marks a block as media upt and then writes it to disk when
Uption is first encountered. No subsequent read of the block will be successful until the block is
Recovered. You can only perform block recovery on blocks that are marked upt or fail
Upload uption check. Block media recovery is already med using the rman recover... BLOCK
Command. By default, RMAN searches the flashback logs for good copies of the blocks, and then
Searches for the blocks in full or level 0 incremental backups. When RMAN finds good copies, it
Restores them and performs media recovery on the blocks.Block media recovery can only use redo
Logs for media recovery, not incremental backups.
The V $ DATABASE_BLOCK_CORRUPTIONview displays blocks marked provided uptBy database
Components such as RMAN commands, ANALYZE, dbv, SQL queries, and so on. The following
Types of types uption result in rows added to this view:
• Physical/Media upload uption: The database does not recognize the block: the checksum is
Invalid, the block contains all zeros, or the block header is fractured. Physical uption
Checking is enabled by default.
• Logical upload uption: The block has a valid checksum, the header and footer match, but
Contents are inconsistent.Block media recovery cannot repair logical block resume uption. Logical
Upload uption checking is disabled by default. You can turn it on by specifying theCHECK
LOGICAL option of the BACKUP, RESTORE, RECOVER, and VALIDATE commands

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