One of the user sessions was terminated abnormally in the middle of a transaction. What
does Oracle database do to recover it?
A.
uses the System Monitor (SMON) background process to perform instance
recovery
B.
uses undo data for roll forward
C.
uses Flashback Log for recovery
D.
uses online redo logs to roll back
E.
uses undo data to roll back the transaction
F.
uses Recovery Manager (RMAN) to roll back
E
sorry answer is A
It’s just a failed user transaction. I don’t think it triggers an instance recovery. It just needs to rollback.
https://docs.oracle.com/cd/B19306_01/server.102/b14220/process.htm
System Monitor Process (SMON)
The system monitor process (SMON) performs recovery, if necessary, at instance startup. SMON is also responsible for cleaning up temporary segments that are no longer in use and for coalescing contiguous free extents within dictionary managed tablespaces. If any terminated transactions were skipped during instance recovery because of file-read or offline errors, SMON recovers them when the tablespace or file is brought back online. SMON checks regularly to see whether it is needed. Other processes can call SMON if they detect a need for it.
With Real Application Clusters, the SMON process of one instance can perform instance recovery for a failed CPU or instance.