20151202 ocp 卷3 30-55
24.which statement is true about loading data using the conventional path of sql*loader
c.no exclusive locks are acquired when the conventional path loads are performed
常规路径加载通过执行sql insert 语句，将表填充到oracle db中。直接路径加载通过格式化oracle
数据库并将其直接写入数据文件，消除了大部分oracle db开销。直接加载不与其他用户争用数据库资源，因此其加载速度通常与磁盘速度相差无几。常规路径加载使用
sql处理和数据库commit操作来保存数据。插入记录组后要执行commit操作。每次加载可能涉及多个事务处理
34.view the exhibit to examine the output of the DBA_OUTSTANDING_ALERT view.
after 30 minutes.you executed the follolowing command:
sql>select reason,metric_value from dba_outstanding_alerts;
REASON METRIC_VALUE
------------------------------ ------------
Tablespace [TEST] is [28 perce 28.125
nt] full
what would be the reason for the elimination of the other rows in the output?c.the threshold alerts conditions are cleard and the alerts are transferred to dba_alert_history
大多数服务器生成的预警是通过对数据库度量设置警告阈值和严重阈值来配置的。可为120多个度量定义阈值，这些度量包括：
每秒的物理读取次数
每秒的用户提交次数
sql服务响应时间
除了表空间的空间占用率与数据库相关外，其他度量都与实例相关。阈值预警又称为‘高状态预警’
清空预警条件后，会自动清空这些预警。有状态预警显示在dbas_outstanding_alerts中，清空后会转到dbaalert_history
服务器生成的其他预警对应于特定的数据库时间。如ora时间，快照太久错误
这些都不是基于阈值的预警，又称无状态预警。无状态预警会直接转到历史记录表。只在oracle control环境中，清空无状态预警才有意义
因为database control 会在自身的资料档案库中存储无状态预警
37.why does performance degrade when many update,insert or delete statemts are issued on a
table that has an associated bitmap index?
c.the smallest index is rebuilt automatically after dml operation
40.while observing the endex statistics ,you find that an index is highly fragment,thereby resulting in poor
database performance,which option would you user to reduce the fragementation without affecting the users who ae currently
using the index?
b.rebult the index using the alter index..rebult online command
通过重建不可用索引来重算指针，可使不可用索引变为有效，重建不可用索引会在新位置重新创建索引，然后会删除不可用缩阴。如使用以下语句来重建索引
alter index hr.emp_empid pk rebult online
使用rebuld online字句，用户可以在重建时继续更新索引表
44.in a new installation of oracle database 11g,you perform these activities;
1.organize software and data on different subdirectories to avoid poor performance
组织软件和数据在不同的子目录，以避免性能较差
2.user consistent naming convertions for database files
使用一致的常规命名数据库文件
3.separate administrator information pertaining to the database in differnt directories
which option corresponds to the type of activities you perfoemed?
c.optimal flesible architecture
最优灵活体系结构 简称ofa
ofa其实就是一种oracle的一种规范，其意义就是用一种统一的给文件和文件夹的规则，和文件存放目录的规则做一个约定。这样，我们不管是安装多个版本的oracle database
也好，因为没uluguifan，这样软件不会冲突，方便管理，文件也方便查找。通过遵循Ofa的知道，使得整个系统可以更加灵活
46.you configured the flash recovery area (FRA) for your database.the database instance is running in archivrelog mode.the default location for the archived redo log files is the falsh recovery area
which two files are removed automatically of the space is required in the fra as per the retention policy?
a.flashback log files
b.backups that have become obsolete
51.view the exahibir and examine the privilewges granted to the sl_rep user.
the emp table is owned by the scott user.the sl_rep user executes the following command:
sql>grant selection on scott.emp to hr
which statemnts describes the outcome of the command?
the command executes successfully
54.in which situation may be the undo_retention parameter be ignored ,even if it is set
to a value?
c.when the undo tablesopace is of a fixed size and retention gurantee is not enabled
有固定的还原表空间，且没有设置retention guarantee强制保留，undo_retention就会被忽略
如果设置了 retention gurantee 即是是固定大小的表空间，也不会忽略Undo_retention,但有可能
出现事务失败