you should be able to:
Manage optimizer statistics
Manage the Automatic Workload Repository (AWR) 自动负载知识库
Use the Automatic Database Diagnostic Monitor (ADDM) 自动数据库诊断监控
Describe and use the advisory framework
Set alert thresholds 阈值
Use server-generated alerts
Use automated tasks
AWR --（严重错误）--> ADR 自动诊断知识库
术语
Automatic Workload Repository (AWR): Infrastructure for data gathering, analysis, and solutions recommendations
AWR Baseline: AWR基线 A set of AWR snapshots for performance comparison
Metric: 度量值 Rate of change in a cumulative statistic
Statistics: 统计信息Data collections providing database and object detail
Optimizer statistics: 优化器统计信息Used by query optimizer
Database statistics: 数据库统计信息Used for performance
Threshold: 阈值A boundary value againstwhich metric values are compared
原文：http://blog.51cto.com/3938853/2162879