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Result Cache In Sga -Oracle Architecture

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 When a query is executed for the very first time, the user’s process searches for the data in the database buffer cache. If data is there, it uses it. otherwise, it performs an I/O operation to retrieve data from the datafile on disk into the buffer cache, and from this data, the final result set is displayed.
 if another query requires the same data set, the process uses the data from the buffer cache to build the result set required by the user. only if it is present in buffer cache.
The Result Cache is an area in the shared pool and contains the end results of a query execution.
The Result Cache can be managed either on the client side or the server side.



Client side
 Result Cache implementation would require the application to use the Oracle Call Interface (OCI) calls.
       
 Server side 
 The query could be executed with a /*+ RESULT CACHE */ hint (or) the result_cache_mode parameter could be set to AUTO.
 If result_cache_mode parameter is set AUTO, It moves all query results to the Result Cache section of the shared pool.


 Cannot cache the result of:
When a query is executed for the very first time.
 when the cache is flushed.

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