20151203 ocp 052 卷3 55-70

56.after performing a clean shut down of the database instance for maintenance.you mount the database and then execute a command to 

open the database;

sql>alter database open;

which two statements are true?

a.the online redo log files and online data files are opened

b.all the online data files headers are checked for consistency 

打开数据库过程包括执行以下任务

打开数据文件

联机重做日志文件

如果尝试打开数据库任一数据文件或者重做日志文件不存在，则oracle服务器返回错误

在最后这个阶段，oracle服务器会验证是否可以打开所有数据文件和联机重做日志文件，还会检查

数据库的一致性。如有必要，系统监视器后台进程将启动实例恢复

61.which two statements are true regarding the oracle data pump export and import operations?

b.you can rename tables during an import operation

在执行导入操作期间重命名表

c.you can overwrite existing dump files during an export operation

在导出操作期间覆盖现有转储文件

64.your database is functional with a prak load for the last one hour .you want to perserve

performance statistics collected during this period to be used for comparison when you analyse the performance 

of the database in the future what action would you tabke toi achive this task?

b.create a baseline on a pire of snapshots spanning the peak-load period

创建一个基线，一对在峰值负载期间快照

66.you have statistics collected for some selected tables.you requirement is that the statistics 

for the tables and all dependent indexes must not be overwritten by further statistics collection until a 

certain point of time .how would youy achive thsi?

a.lock statistics for the tables;

67.which two kinds of failures make the data recovery advisor (DRA) generate 

a manual checklist?

b.failure because a data file is renamed accidently

d.failure due to loss of connectivity-for example .an unplugged disk cable

需要人工干预的故障：例如未插入磁盘电缆的连接故障

可通过撤销以前的错误快速修复的故障：例如，如果错误的重命名了数据文件，则与从备份启动rman还原相比，将该文件重命名回

以前的名称可以更快的修复