Exam 1z0-053 topic 2 question 2 discussion

You have the following requirements in relation to the detection of block corruption for your database instance:
✑ Check for logical self-consistency of data blocks when modified in memory.
✑ Checksums are calculated before and after the block change.
Checks are performed for the lost writes to the physical standby database.

Which method would help you perform the above checks automatically?

Suggested Answer: B 🗳️

Values:

OFF -
When any of DB_BLOCK_CHECKING, DB_BLOCK_CHECKSUM, or DB_LOST_WRITE_PROTECT are explicitly set, no changes are made.

DATA_ONLY -

DATA_AND_INDEX -
DB_BLOCK_CHECKING will be set to FULL.
DB_LOST_WRITE_PROTECT will be set to TYPICAL.
DB_BLOCK_CHECKSUM will be set to FULL.

Values:

OFF or FALSE -
No block checking is performed for blocks in user tablespaces. However, semantic block checking for SYSTEM tablespace blocks is always turned on.

LOW -
Basic block header checks are performed after block contents change in memory (for example, after UPDATE or INSERT statements, on-disk reads, or inter- instance block transfers in Oracle RAC).

MEDIUM -
All LOW checks and full semantic checks are performed for all objects except indexes (whose contents can be reconstructed by a drop+rebuild on encountering a corruption).

FULL or TRUE -
All LOW and MEDIUM checks and full semantic checks are performed for all objects.