OCP 12c题库出现大量新题,062新题-第21题

choose three

Which three statements are true about Oracle checkpoint processing?

A) Incremental checkpoints write some dirty buffers to the datafiles and unwritten redo to the online redo logs.

B) Frequent thread checkpoints can degrade database performance.

C) Thread checkpoints ensure that all dirty buffers are written to data files during a normal shutdown.

D) It reduces the recovery time from instance failures.

E) Database Writer (DBWn) processes write checkpoint information to datafile headers and the control file.

Answer:BCD

(解析:答案BCD比较容易理解,答案E让人觉得是对的,DBWR只负责写脏块,更新检查点信息的事情是由检查点进程来做的。来自3群:1015267481)

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