By default, the driver caches 2 MB of insensitive result set data in memory and writes any remaining result set data to disk. To improve performance when using scroll-insensitive result sets, the driver can cache the result set data in memory instead of writing it to disk. The cursor method is useful for queries that produce a large amount of data, particularly if multiple open result sets are used.ĭata encryption may adversely affect performance because of the additional overhead (mainly CPU usage) required to encrypt and decrypt data. Oracle recommends that you experiment with different setFetchSize() values to determine which value gives the best performance for your application. There is no simple rule for determining the setFetchSize() value that you should use. Performance tests show that, when returning forward-only result sets, the value of tFetchSize() significantly impacts performance. The setFetchSize() method can be used to control the number of rows that are retrieved for each request when forward-only result sets are returned. When returning forward-only result sets, the rows are retrieved from the server in blocks. If set to cursor, a server-side cursor is requested.Typically, the Direct method performs better than the Cursor method. If another query is submitted (using a different statement on the same connection, for example), the driver caches the response to the first query before submitting the second query.
Using this method, the driver must process the entire response to a query before another query is submitted. A server-side database cursor is not created if the requested result set type is a forward-only result set.Typically, responses are not cached by the driver. If set to direct (the default), the database server sends the complete result set in a single response to the driver when responding to a query.
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