|Oracle® Database Administrator's Guide
11g Release 2 (11.2)
|PDF · Mobi · ePub|
To configure the database to use checksums to verify data blocks, set the initialization parameter
TYPICAL (the default). This causes the DBWn process and the direct loader to calculate a checksum for each block and to store the checksum in the block header when writing the block to disk.
The checksum is verified when the block is read, but only if
TRUE and the last write of the block stored a checksum. If corruption is detected, the database returns message
ORA-01578 and writes information about the corruption to the alert log.
The value of the
DB_BLOCK_CHECKSUM parameter can be changed dynamically using the
ALTER SYSTEM statement. Regardless of the setting of this parameter, checksums are always used to verify data blocks in the
See Also:Oracle Database Reference for more information about the