Low hit ratio, but only for indexes

I ran a query on the v$sysstat view to get these results:

NAMESPACE Hit Ratio Pin Hit Ratio Reloads --------------- ---------- ------------- ----------

SQL AREA                98            99        198
TABLE/PROCEDURE         91            93         28
BODY                    93            92          0
TRIGGER                100           100          0
INDEX                   19             3       1588
CLUSTER                 99            99          0
OBJECT                 100           100          0
PIPE                   100           100          0 

As you can see, all the values are great, apart from the INDEX figure which is terrible! Why is this, and how can I improve it?

The SHARED_POOL_SIZE is set to 600MB.

Thanks. Received on Sun Jan 13 2002 - 21:59:06 CST