Prior to this release, when recovery detected corruption in a database, it would make the entire database inaccessible. The database remained unavailable to users until the suspect pages had been repaired or removed from the database.
With recovery fault isolation, a System Administrator has the option of isolating the corrupt pages marked suspect by recovery while the rest of the database is brought online and made available to users.
Recovery fault isolation provides a System Administrator the ability to:
Specify whether an entire database or just the suspect pages become inaccessible when recovery detects corruption
Specify whether a database with suspect pages is brought online in read_only mode
List databases that have suspect pages
List suspect pages by page ID, index ID, and object name
Bring suspect pages online for the System Administrator while they are being repaired
Bring suspect pages online for all database users after they have been repaired
The ability to isolate the suspect pages while bringing the rest of the database online provides a greater degree of flexibility in dealing with data corruption. Problems can be diagnosed, and sometimes corrected, while most of the database is accessible to users. The extent of the damage can be assessed and emergency repairs can be scheduled for a convenient time.
A System Administrator can force offline pages online temporarily, for System Administrator use only, to aid in the analysis and repair of the suspect pages.
Recovery fault isolation applies only to user databases. System databases are always taken entirely offline if they have any suspect pages.
