The DB_BLOCK_CHECKING initialization parameter is set to TRUE. What would be the result of this setting on the data blocks being written to the datafiles, every time the DBWn writes?
A.
The Oracle database will check all data blocks by going through the data on each block, making sure the data is self-consistent.
B.
The DBWn and the direct loader will calculate a checksum and store it in the cache header of every data block when writing it to disk.
C.
The Oracle database will check data blocks belonging to the SYSTEM tablespace only, by going through the data on each block, making sure the data is self-consistent.
D.
The Oracle database will check data blocks belonging to the SYSAUX tablespace only, by going through the data on each block, making sure the data is self-consistent.
E.
The Oracle database will check data blocks in the SYSTEM and SYSAUX tablespaces only, by going through the data on each block, making sure the data is self-consistent.
Explanation:
Initialization Parameter: DB_BLOCK_CHECKING
The DB_BLOCK_CHECKING initialization parameter invokes the same checks as events 10210, 10211, and 10212. The default setting is FALSE and is provided for compatibility with earlier releases where block checking is disabled as a default. However, block checking for the SYSTEM tablespace is always turned on.
When this parameter is set to TRUE, Oracle Database performs block checking for all data blocks. Oracle Database checks a block by reading the data on the block and making sure it is self-consistent.
Ref.:
Oracle Database 10g: Administration Workshop II. Page: 11-9.