Which three statements are true about Automatic Workload Repository (AWR)?
A. All AWR tables belong to the SYSTEM schema.
B. The AWR data is stored in memory and in the database.
C. The snapshots collected by AWR are used by the self-tuning components in the database
D. AWR computes time model statistics based on time usage for activities, which are displayed in the v$SYS time model and V$SESS_TIME_MODEL views.
E. AWR contains system wide tracing and logging information.
* A fundamental aspect of the workload repository is that it collects and persists database performance data in a manner that enables historical performance analysis.
The mechanism for this is the AWR snapshot. On a periodic basis, AWR takes a “snapshot” of the current statistic values stored in the database instance’s memory and persists them to its tables residing in the SYSAUX tablespace.
* AWR is primarily designed to provide input to higherlevel components such as automatic tuning algorithms and advisors, but can also provide a wealth of information for the manual tuning process.