New Features for Administrators - Question 075

Users complain that SQL statements using a particular index fail. Using DBVERIFY, you find that two separate blocks in the index have become corrupt. The database data files for user data and index are very large. What is the least disruptive recovery strategy available in Oracle9i?

A. Rebuild the index using the online option.

B. Take the individual data file offline (not the whole tablespace), restore and recover the data file from backup with RMAN, then set the data file online again.

C. Without setting the individual data file offline, use RMAN with Block Media Recovery to restore and recover only those blocks.

D. Take the individual data file (not the whole tablespace) offline, use RMAN with Block Media Recovery to restore and recover only those blocks, then set the data file online again.

Answer: C

Explanation:

You can use RMAN with Block Media Recovery to restore and recover only those blocks. It is not required to set the individual data file offline. BMR enables you to back up specific blocks in a datafile without taking the database offline. The default backup method is datafile media recovery. You use the new BLOCKRECOVER statement to perform BMR.

Incorrect Answers

A: With corrupted blocks you cannot rebuild the index. You need restore and recover these blocks.

B: It is not required to take the individual data file offline to perform the blocks restore and recovery.

D: It is not required to take the individual data file offline to perform the blocks restore and recovery.

OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 186

Chapter 3: Manageability Enhancements

Oracle 9i New Features, Robert Freeman, p. 84-86

Chapter 3: New Oracle9i Availability and Recoverability Features