Oracle Database Administration II — Question 144

Which two are true about Oracle instance recovery? (Choose two.)

Answer options

• A. Recovery begins from the beginning of the CURRENT redo log group.
• B. Recovery begins from the last checkpoint position that was calculated by the Database Writer before instance failure.
• C. Recovery begins from the start of any ACTIVE redo log group or the start of the CURRENT log group if no other group is ACTIVE.
• D. Recovery reads redo until the end of the redo thread. SMON rolls back any dead transactions, and then the database is opened.
• E. Recovery begins from the last checkpoint position that was recorded in the control file by the checkpoint process (CKPT).
• F. Recovery reads redo until the end of the redo thread, and then opens the database. SMON then rolls back any dead transactions.

Correct answer: E, F

Explanation

The correct answers E and F accurately describe the recovery process in Oracle. E states that recovery starts from the last checkpoint recorded in the control file, which is essential for ensuring data consistency. F correctly details the process of reading redo logs until the end of the thread and the role of SMON in rolling back dead transactions before opening the database. Options A, B, C, and D do not accurately reflect the mechanisms involved in instance recovery.