![]() ![]() If the optimizer statistics indicate that 80% of employees are managers, then the optimizer may decide that a full table scan is most efficient. For a specific query in a given environment, the cost computation accounts for factors of query execution such as I/O, CPU, and communication.įor example, a query might request information about employees who are managers. The optimizer uses available statistics to calculate cost. The optimizer choose the plan with the lowest cost among all considered candidate plans. The optimizer attempts to generate the most optimal execution plan for a SQL statement. ![]()
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