Identify two effects of the DB_FILE_MULTIBLOCK_READ_COUNT parameter on the optimizer. (Choose two.)
A. Decreasing the value of DB_FILE_MULTIBLOCK_READ_COUNT from the default increases the cost of index probes for DSS workloads.
B. A full table scan can become cheaper than index scans if the database instance has a high enough DB_FILE MULTIBLOCK_READ_COUNT for both OLTP and DSS workloads.
C. Increasing the value of DB_FILE_MULTIBLOCK_READ_COUNT within OS limits lowers the costing of an index probe that is done in conjunction with a nested loop for OLTP workloads.
D. In DSS workloads where full table scans may run in parallel and bypass the buffer cache, decreasing the value of DB_FILE_MULTIBLOCK_READ_COUNT from the default increases the cost of full table scans. E. Increasing the value of DB_FILE_MULTIBLOCK_READ_COUNT within OS limits lowers the cost of full table scans and can result in the optimizer choosing a full table scan over an index scan for both OLTP and DSS workloads.
Identify two effects of the DB_FILE_MULTIBLOCK_READ_COUNT parameter on the optimizer. (Choose two.)
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