主动式维护
被动是维护(critical)
AWR本身就是一个数据库,专门用来存放数据库本身运行信息的,通直接的用户数据、业务数据无关.AWR是oracle自我管理的一个基础.
Ojbectives
After completing this lesson,you should be able to :
- Manage optimizer statistics
- Manage the Automatic Workload Repository(AWR
- Use the Automatic Database Diagnostic Monitor(ADDM)
- Describe and use the advisory framework
- Set alert thresholds
- Use server-generated alerts
- Use automated tasks
Databaes Maintenance
Viewing the Alert History
Terminology
- Automatic workload reponsitory(AWR):Infrastructure for data gathering,analysis,and solutions recommedations
- AWR Baseline:A set of AWR snapshots for performance comparison
- Metric:Rate of change in a cumulative statistic
- Statistics:Data collections providing database and object detail
- Optimizer statistics:Used by query optimizer
- Database statistics:Used for performance
- Threshold:A boundary value against which metric values are compared