Whenever there is block corruption during recovery then you have to choice whether you will corrupt the block or will open the database with RESETLOGS options.
The general rule is if the block is unimportant and if the problem is isolated then corrupt the block. But if the problem is not isolated then open the database with RESETLOGS option.
Oracle database supports trial recovery in order to identify corrupt blocks. In case of trial recovery the database writes errors generated during trial recovery to alert files and marks the data block as corrupt in memory and thus allow recovery to proceed.
When trial recovery ends, the database removes all effects of the test run from the system—except the possible error messages in the alert files. If the instance fails during trial recovery, then the database removes all effects of trial recovery from the system because trial recovery never writes changes to disk.
You can perform trial recovery by, RECOVER ... TEST option.
Example:
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RECOVER DATABASE TEST
RECOVER DATABASE USING BACKUP CONTROLFILE UNTIL CANCEL TEST
RECOVER TABLESPACE sysaux TEST
RECOVER DATABASE UNTIL CANCEL TEST
Related Documents:
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Block Media Recovery with RMAN
Extract data from corrupt block
Verify Physical data Structure
Allow recovery to corrupt blocks
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