Chapter 11, Problem 11RQ

Explanation of Solution

Optimizer hint and its usage:

• Special instructions that are embedded inside the SQL (Structured Query Language) command test for the optimizer is called as optimizer hints.
• Optimizer performs well in choice of the best execution plan in most of the circumstances and there are some situations where the optimizer fails to choose the best execution plan.
• Based on the statistics that exists an optimizer makes decision.
• The statistics that are obtained by the optimizer can be old and that could be the reason for most of optimizer not chooses the best execution plan.
• There are situations where even though a good statistics are obtained, the choice made by the optimizer may not be worthy...