Snapshot Workload Repository & Retention

DBA_HIST_SNAPSHOT displays information about the snapshots in the Workload Repository.
It results Snapshots for each instance Time at the beginning of the snapshot interval, Time at the end of the snapshot interval, Startup time of the instance, Snapshot level, Number of errors occurring in the tables for the particular snapshots.

column BEGIN_INTERVAL_TIME format a25
column END_INTERVAL_TIME format a25
column STARTUP_TIME format a25
set lines 1000
select instance_number, snap_id , BEGIN_INTERVAL_TIME, END_INTERVAL_TIME,
STARTUP_TIME from dba_hist_snapshot where dbid=(select dbid from v$database)
and BEGIN_INTERVAL_TIME between to_date('12-feb-2012','dd-mon-yyyy') and to_date('13-feb-2012','dd-mon-yyyy') and instance_number in (select instance_number from v$instance)order by BEGIN_INTERVAL_TIME asc;







SNAPSHOT Retention:-

col SNAP_INTERVAL for a20
col RETENTION for a20
select * from dba_hist_wr_control;