kaywang 发表于 2015-11-8 17:27:13

OCP-1Z0-053-V12.02-298题


298.While tuning a SQL statement, the SQL Tuning Advisor finds an existing SQL profile for the statement
that has stale statistics available.
What would the optimizer do in this situation?
A. It updates the existing SQL profiles with current statistics.
B. It makes the statistics information available to GATHER_STATS_JOB.
C. It initiates the statistics collection process by running GATHER_STATS_JOB.
D. It logs a warning message in the alert log so that the DBA can perform statistics collection manually.
Answer: B
答案解析:
Actions represent the jobs that are performed by a module. For example, the DBMS_SCHEDULER modulecan run the GATHER_STATS_JOB action to gather statistics on all database objects. If a single action is using the majority of the wait time, then you should investigate it.

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