You are in the middle of a transaction updating a very important table. The machine on which a
database was running reboots because of power outage. This caused a database instance failure.
Which statement is true in this situation?
A.
The online redo log files and archived redo log files are required to accomplish the recovery
B.
The uncommitted transaction will be committed at the next startup of the database instance
C.
The uncommitted transaction is rolled back automatically at the next opening of the database
D.
The DBA has to perform the recovery on the database to recover the uncommitted transaction
Uncommitted changes are not visible outside of the connection, so the time of the rollback is irrelevant. So the transaction is eventually rolled back.
Oracle performs crash recovery and instance recovery automatically after an instance failure.
Crash and instance recovery involve two distinct operations: rolling forward the current, online datafiles by applying both committed and uncommitted transactions contained in online redo records, and then rolling back changes made in uncommitted transactions to their original state.
https://docs.oracle.com/cd/B10501_01/server.920/a96519/intro.htm