题目：
44. Your database is functional with a peak load for the last one hour. You want to preserve the
performance statistics collected during this period to be used for comparison when you analyze the
performance of the database in the future.
What action would you take to achieve this task?
A.Insert finding directives for ADDM tasks in the future.
B.Create a baseline on a pair of snapshots spanning the peak-load period.
C.Decrease the snapshot interval in the AWR to collect more snapshots during the peak-load period.
D.Set the snapshot retention period in the Automatic Workload Repository (AWR) to zero to avoid automatic purging of snapshots
参考答案 B
解析：
题目意思是数据库经历了一个高峰期。想将这个期间的统计信息保留下来，和未来的性能做对比。需要怎么做。根据题目意思。做个baseline基线就可以了。
官方文档：
https://docs.oracle.com/cd/E11882_01/server.112/e41573/autostat.htm#PFGRF94177
5.2.2 Baselines
A baseline contains performance data from a specific time period that is preserved for comparison with other similar workload periods when performance problems occur. The snapshots contained in a baseline are excluded from the automatic AWR purging process and are retained indefinitely.
There are several types of available baselines in Oracle Database: