Enabling the Automatic Workload Repository

Gathering database statistics using AWR is enabled by default and is controlled by theSTATISTICS_LEVEL initialization parameter.

The automatic snapshot operations are scheduled, so that they get executed automatically at a particular time. The database can be configured so that the AWR reports use the database time zone instead of the operating system time zone. Refer to TIME_AT_DBTIMEZONE.

To enable statistics gathering by AWR:

Set the STATISTICS_LEVEL parameter to TYPICAL or ALL.

The default setting for this parameter is TYPICAL.

Setting STATISTICS_LEVEL to BASIC disables many Oracle Database features, including AWR, and is not recommended. If STATISTICS_LEVEL is set to BASIC, you can still manually capture AWR statistics using the DBMS_WORKLOAD_REPOSITORY package. However, because in-memory collection of many system statistics—such as segments statistics and memory advisor information—will be disabled, the statistics captured in these snapshots may not be complete.