col STAT_NAME for a20
col VALUE_DIFF for 9999999999
col STAT_PER_MIN for 9999,999,999
set lines 200 pages 1500 long 99999999
col BEGIN_INTERVAL_TIME for a30
col END_INTERVAL_TIME for a30
set pagesize 40
set pause on
 
 
select hsys.SNAP_ID,
       hsnap.BEGIN_INTERVAL_TIME,
       hsnap.END_INTERVAL_TIME,
           hsys.STAT_NAME,
           hsys.VALUE,
           hsys.VALUE - LAG(hsys.VALUE,1,0) OVER (ORDER BY hsys.SNAP_ID) AS "VALUE_DIFF",
           round((hsys.VALUE - LAG(hsys.VALUE,1,0) OVER (ORDER BY hsys.SNAP_ID)) /
           round(abs(extract(hour from (hsnap.END_INTERVAL_TIME - hsnap.BEGIN_INTERVAL_TIME))*60 +
           extract(minute from (hsnap.END_INTERVAL_TIME - hsnap.BEGIN_INTERVAL_TIME)) +
           extract(second from (hsnap.END_INTERVAL_TIME - hsnap.BEGIN_INTERVAL_TIME))/60),1)) "STAT_PER_MIN"
from dba_hist_sysstat hsys, dba_hist_snapshot hsnap where
 hsnap.BEGIN_INTERVAL_TIME between to_date('30-11-2019','DD-MM-YYYY') and  to_date('01-12-2019','DD-MM-YYYY')
 and hsys.snap_id = hsnap.snap_id
 and hsnap.instance_number in (select instance_number from v$instance)
 and hsnap.instance_number = hsys.instance_number
 and hsys.STAT_NAME='logons current'
 order by 1;