查看scnheadroom变化趋势的几种方法(四)
(to_number(to_char(tim,'MI'))*60) +
(to_number(to_char(tim,'SS')))
) * (16*1024)) chk16kscn
from
(
select FIRST_TIME tim , FIRST_CHANGE# gscn,
((NEXT_CHANGE#-FIRST_CHANGE#)/
((NEXT_TIME-FIRST_TIME)*24*60*60)) rate
from v$archived_log
where (next_time > first_time)
)
)
order by 1,2
;