ORACLE scn-headroom Check

Select Tim, GSCN, round (rate), round ((CHK16KSCN-GSCN)/24/3600/32/1024,90) "Headroom" from (select Tim, GSCN, Rate, (( (To_number (To_char (Tim, ' YYYY ')) -1988) *12*31*24*60*60) + ((To_number (To_char (Tim, ' MM '))-1) *31*24*60*60) + (((to_ Number (To_char (Tim, ' DD '))-1)) *24*60*60) + (To_number (To_char (Tim, ' HH24 ')) *60*60) + (To_number (To_char (Tim, ' MI ')) * ) + (To_number (To_char (Tim, ' SS '))) * (16*1024)) Chk16kscn from (select First_time Tim, first_change# Gscn, (next_ch ange#-first_change#)/((next_time-first_time) *24*60*60)) rate from (select First_time, Leads (First_time, 1) Over (order by First_time) as Next_time, first_change#, next_change# from V$log_history where Thread#=1) where (Next_time > first_t IME)) where Tim > Sysdate-3 order by Tim Desc;

ORACLE scn-headroom Check