Query to check the generation of all redo during the time period

Description:

This query used to check the generation of all redo during the time period.

Script:

select to_char(begin_interval_time,'YYYY_MM_DD HH24:MI') snap_time,
        dhsso.object_name,
        sum(db_block_changes_delta)
  from dba_hist_seg_stat dhss,
         dba_hist_seg_stat_obj dhsso,
         dba_hist_snapshot dhs
  where dhs.snap_id = dhss.snap_id
    and dhs.instance_number = dhss.instance_number
    and dhss.obj# = dhsso.obj#
    and dhss.dataobj# = dhsso.dataobj#
    and begin_interval_time between to_date('2021_06_20 12','YYYY_MM_DD HH24')
                                           and to_date('2021_06_21 12','YYYY_MM_DD HH24')
  group by to_char(begin_interval_time,'YYYY_MM_DD HH24:MI'),
           dhsso.object_name