Disabling oracle cache

Hi,
I am a graduate student in Computer Science and need to do some experiments for my thesis. I am not very familiar with oracle. I am using oracle and have implemented a cache to store some of the frequently used data items in my application.
I am connecting to oracle using the ODBC driver 9.0.2, the one that comes with oracle 9i client installation.
To measure the performance of the cache, I need to disable any other cache implemented by the oracle client or the server. Is there any way by which I can do that? I know oracle does do some of its own caching.
Is there any way in which I can disable the oracle cache? Please refer me to the appropriate documentation.
Something that I can give in my query. I am not the DBA. It is ok even if there is a directive in the query to tell oracle to bypass the cache. That will also work for me.
Thanks,
Nishant
Thanks,
Nishant

You can flush the shared pool
ALTER SYSTEM FLUSH SHARED_POOLwhich will flush the buffer cache. This will clear the cache on the server. I don't believe it is possible to tell Oracle not to cache buffers it reads from disk, though.
What sort of client-side caches are you thinking of? The client will automatically fetch rows you may not have requested yet (i.e. fetch the first 10 rows from SELECT * FROM <<someLargeTable>> when the application requests the first row). That is covered by the prefetch count in the ODBC DSN. Not sure what a value of 0 means, though-- that may specify that the default value be used.
What about things like the operating system cache (assuming you're not using raw devices) or the hardware disk cache. I don't think you can disable those.
Justin
Distributed Database Consulting, Inc.
http://www.ddbcinc.com/askDDBC

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