Set Feedback Off
Set Echo Off
Set Heading Off
Set Term Off

Column Instance New_Value _Instance NoPrint
SELECT 'OHR_' || name Instance FROM v$database;

spool &&_instance..txt

-- DATA CACHE Hit Ratio INFORMATION

select sum((1-(pr.value/(dbg.value+cg.value)))*100) hit_ratio
from v$sysstat pr, v$sysstat dbg, v$sysstat cg
where pr.name = 'physical reads'
and dbg.name = 'db block gets'
and cg.name = 'consistent gets';

spool off;
Set Feedback On
Set Echo On
Set Heading On
Set Term On

exit;