Media recovery can sometimes be stopped by the inability to read past a certain point in the redo stream. This is often referred to as "stuck recovery."
Before Oracle9i, the Database Administrator had few options to deal with stuck recovery. If the corrupt redo could not be recovered from some other source, then all transactions that committed after the corrupt point in the redo stream would be lost.
Oracle9i changes that with the Trial Recovery feature. Trial Recovery is used to test the application of the redo logs to the database.
What are three other characteristics of Trial Recovery? (Choose three.)
A. Speeds up subsequent media recovery actions
B. Writes any uncorrupted blocks to disk during the test recovery
C. Can be invoked by adding the TEST option to any RECOVER command
D. Allows the Administrator to determine how many blocks are affected by corruption
E. Marks blocks as corrupt in memory, allowing the test recovery to proceed to completion
Answer: A, D, E
Explanation:
Trial Recovery feature is used to speed up subsequent media recovery actions. It allows the Administrator to determine how many blocks are affected by corruption, mark them as corrupt in memory to allow the test recovery proceed to completion.
Incorrect Answers
B: It does not write uncorrupted blocks to disk during the test recovery.
C: There is no TEST option in RECOVER command.
OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 186-187
Chapter 3: Manageability Enhancements
Oracle 9i New Features, Robert Freeman, p. 73-86
Chapter 3: New Oracle9i Availability and Recoverability Features
No comments:
Post a Comment