oracle memory management

Dear Oracle-Freaks,

I have got a problem concerning the usage of the main memory during an oracle session.
Is there a chance to influence the usage of the memory? I have several tables in use, some to query and to update, two tables are only used for protocol the actions. How can I succeed in giving most of memory to the tables I want to select from or update to and how can I minimise the memory for the two tables where I only append tuples with new protocol information?
Is there a possibility to arrange and control the partitioning of the main memory?
I guess, that this may be a question of general interest. If I get any mails, I will post the results.

Thanks for any help or advice where to find answers in books or in the oracle documentation

Manfred Tischendorf

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