快照
SQL> col begin_interval_time for a30
SQL> col end_interval_time for a30
SQL> select snap_id, 
    to_char(begin_interval_time,'yyyy-mm-dd hh34:mi:ss') begin_interval_time,
    to_char(end_interval_time,'yyyy-mm-dd hh34:mi:ss') end_interval_time
    from dba_hist_snapshot order by 1;
    
   SNAP_ID BEGIN_INTERVAL_TIME            END_INTERVAL_TIME
---------- ------------------------------ ------------------------------
       155 2018-06-25 19:00:22            2018-06-25 20:00:25
       156 2018-06-25 20:00:25            2018-06-25 21:00:27
       157 2018-06-25 21:00:27            2018-06-25 22:00:33
       158 2018-06-25 22:00:33            2018-06-25 23:00:36
       159 2018-06-25 23:00:36            2018-06-26 00:00:39
       160 2018-06-26 00:00:39            2018-06-26 01:00:41
       161 2018-06-26 01:52:17            2018-06-26 02:04:22
       162 2018-06-26 02:04:22            2018-06-26 03:00:24
       163 2018-06-26 03:00:24            2018-06-26 04:00:27
       164 2018-06-26 04:00:27            2018-06-26 05:00:29
       165 2018-06-26 05:00:29            2018-06-26 06:00:32
       
SQL> exec dbms_workload_repository.create_snapshot();
PL/SQL procedure successfully completed.

SQL> exec dbms_workload_repository.drop_snapshot_range(low_snap_id=>150,high_snap_id=>154);
PL/SQL procedure successfully completed.

SQL> col snap_interval for a20
SQL> col retention for a20
SQL> select snap_interval,retention,topnsql from dba_hist_wr_control;
SNAP_INTERVAL        RETENTION            TOPNSQL
-------------------- -------------------- ------------------------------
+00000 01:00:00.0    +00008 00:00:00.0    DEFAULT

SQL> exec dbms_workload_repository.modify_snapshot_settings(retention=>15*1440,interval=>30);
PL/SQL procedure successfully completed.

SQL> select snap_interval,retention,topnsql from dba_hist_wr_control;

SNAP_INTERVAL        RETENTION            TOPNSQL
-------------------- -------------------- ------------------------------
+00000 00:30:00.0    +00015 00:00:00.0    DEFAULT

基线
SQL> exec dbms_workload_repository.create_baseline(start_snap_id=>155,end_snap_id=>156,baseline_name=>'baseline01');
PL/SQL procedure successfully completed.

SQL> col baseline_name for a30
SQL> select baseline_name,baseline_id,start_snap_id,end_snap_id from dba_hist_baseline;

BASELINE_NAME                  BASELINE_ID START_SNAP_ID END_SNAP_ID
------------------------------ ----------- ------------- -----------
baseline01                               1           155         156
SYSTEM_MOVING_WINDOW                     0             1         168

SQL> exec dbms_workload_repository.drop_baseline(baseline_name=>'baseline01',cascade=>false);
PL/SQL procedure successfully completed.

SQL> select baseline_name,baseline_id,start_snap_id,end_snap_id from dba_hist_baseline;

BASELINE_NAME                  BASELINE_ID START_SNAP_ID END_SNAP_ID
------------------------------ ----------- ------------- -----------
SYSTEM_MOVING_WINDOW                     0             1         168

报告
SQL> @?/rdbms/admin/awrrpt.sql  --生成最常见的AWR报告方式

SQL> @?/rdbms/admin/awrddrpt.sql --比较两个AWR报告

SQL> @?/rdbms/admin/awrsqrpt.sql --生成AWR报告中指定sql_id的执行计划