oracle-oc-043试题分类汇总.docxVIP

性能调优 1.You observe that a database performance has degraded over a period of time. While investigating the reason, you find the size of the database buffer cache is not large enough to cache all the needed data blocks. Which advisory component wold you refer to, in order to determine that required size of the database buffer cache? A. Memory Advisor B. Segment Advisor C. SQL Tuning Advisor D. SQL Access Advisor E. Automatic Database Diagnostic Monitor(ADDM) A 发现数据库运行一段时间后性能下降了，调查发现原因是因为buffer cache不能装下所有需要的数据块，用个工具确定数据库所需要的buffer cache的大小。 2.Exhibit --显示所有日志在同一个目录下 In your production database, the total waits and the time waited for log file parallel write are significantly high. While investigating the reason, you find that there are three redo log groups with two members in each group, and all redo log members are places on a single physical disk. What action would you take to minimize the waits? A. Start the log writer slave processes B. Increase the number of redo log files C. Increase the size of the redo log buffer D. Place the redo log files on the different disks. E. Increase the number of log writer processes. Answer:D 等待并行写日志的时间明显很高。调查发现三个日志文件组，每组由两个成员，都在同一个物理磁盘上。通过什么方法解决问题？--主要是不懂题目意思会出错。 24. You are designing an application for Certkiller .com and you have been asked to design a database table to facilitate monthly bill gen eration. The bill would include details of customer calls, listed in chronological order. Which method would you follow to achieve this ob jective without increasing the overhead of sorting the rows? A. create a hash cluster to store the data B. create an index cluster to store the data C. create a partitioned table to store the data D. create a sorted hash cluster to store the data E. create a heap table with rowid to store the data Answer: D 27. In which scenarios would you rebuild an index? (Choose all that a pply.) A. when you need to disable the index usage B. when you n