You execute the following command to perform I/O calibration after the declaration of bind variables in the session that are used in the command:
SQL> EXECUTE dbms_resource_manager.calibrate_io( num_physical_disks=>1, - max_latency=>50,
-max_iops=>:max_iops, -max_mbps=>:max_mbps, - actual_latency=>:actual_latency);
Which statement describes the consequence?
A. The command produces an error.
B. The calibration process runs successfully and populates all the bind variables.
C. The calibration process runs successfully but the latency time is not computed.
D. The calibration process runs successfully but only the latency time is computed.
答案：（A）
解析：
首先题目有问题：当statistics_level != basic时，timed_statistics必须 = true
运行 I/O 校准需要保证以下条件：
? sysdba 权限；
? filesystemio_options=[asynch | setall]；
? timed_statistics=true ；
filesystemio_options=[none | directio] 会遇到 ORA-56708，timed_statistics = false 会遇到 ORA-56709