What can you conclude based on this ratio?

You work as a DBA and have the responsibility of managing a large online transaction processing
(OLTP) system. You used the following query during the performance tuning activity:
SQL> SELECT (1-((phy.value-phyd.value) / (cur.value + con.value))) * 100
2 “Cache Hit ratio”
3 FROM v$sysstat cur, v$sysstat con, v$sysstat phy, v$sysstat phyd
4 WHERE cur.name = ‘db block gets’
5 AND con.name = ‘consistent gets’
6 AND phy.name = ‘physical reads’
7 AND phyd.name = ‘physical reads direct’;
Cache Hit Ratio
—————98.43
What can you conclude based on this ratio?

A.
The database performance is very good because of reduced logical I/Os.

B.
The database performance cannot be determined based only on this ratio.

C.
Good database performance is guaranteed because very few physical I/Os are performed.

D.
The database performance is very good because most of the requested data blocks are found
in the buffer cache.