You need to migrate database from oracle Database 10g to 11g. You want the SQL workload to start the 10g plans in the 11g database instance and evolve better plans. Examine the following steps: 1…

Question

Options

• A1, 2, 3, 4, 5, 6, 7,
• B4, 8, 10
• C1, 2, 3, 4, 8, 10
• D1, 2, 3, 6, 9, 5
• E1, 2, 3, 5, 9, 10

• B
  9% (2)
• C
  83% (19)
• D
  4% (1)
• E
  4% (1)

Explanation

By setting the parameter OPTIMIZER_FEATURES_ENABLE to the 10g version used before the upgrade, you should be able to revert back to the same execution plans you had prior to the OPTIMIZER_CAPTURE_SQL_PLAN_BASELINES In Oracle Database 11g a new feature called SQL Plan Management (SPM) has been introduced to guarantees any plan changes that do occur lead to better performance. When OPTIMIZER_CAPTURE_SQL_PLAN_BASELINES is set to TRUE (default FALSE) Oracle will automatically capture a SQL plan baseline for every repeatable SQL statement on the system. The execution plan found at parse time will be added to the SQL plan baseline as an accepted OPTIMIZER_USE_SQL_PLAN_BASELINES enables or disables the use of SQL plan baselines stored in SQL Management Base. When enabled, the optimizer looks for a SQL plan baseline for the SQL statement being compiled. If one is found in SQL Management Base, then the optimizer will cost each of the baseline plans and pick one with the lowest cost.

No community discussion yet for this question.