OCP-1Z0-053-V12.02-493题

493.Which three statements about performance analysis by SQL Performance Analyzer are true?

(Choose three.)

A. It detects changes in SQL execution plans.

B. It produces results that can be used to create the SQL plan baseline.

C. The importance of SQL statements is based on the size of the objects accessed.

D. It generates recommendations to run SQL Tuning Advisor to tune regressed SQLs.

E. It shows only the overall impact on workload and not the net SQL impact on workload.

Answer: ABD


答案解析:

参考:http://docs.oracle.com/cd/E11882_01/server.112/e41481/spa_intro.htm#RATUG174


SQL Performance Analyzer compares the performance of SQL statements before and after the change and produces a report identifying any changes in execution plans or performance of the SQL statements.


Fixing Regressed SQL Statements

If the performance analysis performed by SQL Performance Analyzer reveals regressed SQL statements, then you can make changes to remedy the problem. For example, you can fix regressed SQL by running SQL Tuning Advisor or using SQL plan baselines. You can then repeat the process of executing the SQL statements and comparing its performance to the first execution. Repeat these steps until you are satisfied with the outcome of the analysis



原文地址:https://www.cnblogs.com/hzcya1995/p/13316429.html