多项选择题 You work as a database administrator for Certkiller .com. Users in the Certkiller PROD database complain about the slow response when accessing the database. In the Active Session Waiting： Configuration page you find that the majority of the wait time is for the redo log buffer.Further investigation using the Run Queue graph and operating system tools reveals that the redo log files are on the same disks， and that the disk I/O for the redo log files is the reason for the performance degradation.  Which two actions would you take to gain performance？（）

单项选择题 You work as a database administrator for Certkiller .com. Redo log files are not multiplexed in your database. Redo log blocks are corrupted in group 2， and archiving has stopped. All the redo logs are filled and database activity is halted. Database writer has written everything to disk.  Which command would you execute to proceed further？（）

单项选择题 YouworkasadatabaseadministratorforCertkiller.com.Inyourdatabaseserver，theparameterPLSQL_OPTIMIZE_LEVELhasbeensetto2.Whatwouldthissettingachieve？（）