132. You are in the middle of a transaction and very crucial data has been modified. Because of a hardware failure, the instance has shut down before synchronizing all the database files. Which two statements are true? (Choose two.)
A) On startup, SMON coordinates instance recovery.
B) On startup, CKPT coordinates instance recovery.
C) On startup, use RMAN to perform. instance recovery.
D) Uncommitted changes will be rolled back after the database is opened.
E) On startup, perform. media recovery and then instance recovery.
F) On startup, all the files will be synchronized and you get both committed and uncommitted data.
答案：AD
由于硬件损坏，类似意外掉电，这就意味着shutdown abort,当重新启动后SMON进程会自动恢复实例，uncommited的数据会自动rollback,同时,commited的数据而又未写到datafile中的会被写进datafile中。并没有数据文件丢失，不需要介质恢复,E错,容易迷惑
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.
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