OCP-1Z0-053-V12.02-46题

46.What happens when you run the SQL Tuning Advisor with limited scope?
A. Access path analysis is not performed for SQL statements.
B. SQL structure analysis is not performed for SQL statements.
C. SQL Profile recommendations are not generated for SQL statements.
D. Staleness and absence of statistics are not checked for the objects in the SQL Tuning Advisor.
Answer: B
答案解析：
参考：/article/1628968.html

参考：http://docs.oracle.com/cd/E11882_01/server.112/e41573/sql_tune.htm#PFGRF94853

选择优化任务的适当范围很重要。如果选择“Limited（有限制）”选项，SQL 优化指导会根据统计信息检查结果、访问路径分析结果和SQL 结构分析结果来生成建议。“Limited（有限制）”选项不会产生SQL 概要文件建议。如果选择“Comprehensive（综合）”选项，SQL 优化指导不仅会生成“Limited（有限制）”选项生成的所有建议，在SQL
概要分析模式下还会调用优化程序来构建SQL 概要文件。使用“Comprehensive（综合）”选项时，还可以指定优化任务的时间限制，该时间限制的默认值是30 分钟。

在有限范围使用SQL Tuning Advisor 会发生什么？

SQL Tuning Advisor provides options to manage the scope and duration of a tuning task. You can set the scope of a tuning task either of the following:

Limited

In this case, SQL Tuning Advisor produces recommendations based on statistical checks, access path analysis, and SQL structure analysis. SQL profile recommendations are not generated.

Comprehensive

In this case, SQL Tuning Advisor carries out all the analysis it performs under limited scope plus SQL Profiling. With the comprehensive option you can also specify a time limit for the tuning task, which by default is 30 minutes.

根据官方文档，此题应该选C，而不是B.