Oracle OCP 1Z0 053 Q201(DBMS_SPM.EVOLVE_SQL_PLAN_BASELINE)

201.Examine the following PL/SQL block:
SET SERVEROUTPUT ON 
SET LONG 10000 
DECLARE 
  report clob;
BEGIN report := DBMS_SPM.EVOLVE_SQL_PLAN_BASELINE();
  DBMS_OUTPUT.PUT_LINE(report);
END;
Which statement describes the effect of the execution of the above PL/SQL block?
A. The plan baselines are verified with the SQL profiles.
B. All fixed plan baselines are converted into nonfixed plan baselines.
C. All the nonaccepted SQL profiles are accepted into the plan baseline.
D. The nonaccepted plans in the SQL Management Base are verified with the existing plan baselines.
Answer: D

The PL/SQL function DBMS_SPM.EVOLVE_SQL_PLAN_BASELINE tries to evolve new plans that have been added by the optimizer to the plan history of existing plan baselines.
If the function can verify that the new plan performs better than a plan chosen from the corresponding SQL plan baseline, then the database adds the new plan as an accepted plan.

SQL> SET SERVEROUTPUT ON 
SQL> SET LONG 10000 
SQL> DECLARE 
  2    report clob;
  3  BEGIN report := DBMS_SPM.EVOLVE_SQL_PLAN_BASELINE();
  4    DBMS_OUTPUT.PUT_LINE(report);
  5  END;
  6  /


-------------------------------------------------------------------------------


                        Evolve SQL Plan Baseline
Report
-------------------------------------------------------------------------
------


Inputs:
-------
  SQL_HANDLE = 
  PLAN_NAME  = 
  TIME_LIMIT =
DBMS_SPM.AUTO_LIMIT
  VERIFY     = YES
  COMMIT     =
YES


---------------------------------------------------------------------------
----
                                 Report
Summary
------------------------------------------------------------------------
-------
There were no SQL plan baselines that required processing.




PL/SQL procedure successfully completed.

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