58.Which statement is true when Automatic Workload Repository (AWR) baselines are created using
baseline templates?
A. AWR baselines are always created as repeating baselines.
B. AWR baselines can be created on the basis of two time values.
C. AWR baselines are always created with infinite expiration duration.
D. AWR baselines are always created using the Automatic Workload Repository (AWR) retention period
as expiration duration.
Answer: B
答案解析：
参考：http://docs.oracle.com/cd/E11882_01/server.112/e40540/cncptdba.htm#CNCPT89120
An AWR baseline is a collection of statistic rates usually taken over a period when the system is performing well at peak load. You can specify a pair or range of AWR snapshots as a baseline. By using an AWR report to compare statistics captured during a period of bad performance to a baseline, you can diagnose problems.