wangtong
发表于 2016-10-20 10:23:43
50:
View the Exhibit to examine the output for the CROSSCHECK BACKUP command.
Which statement is true about the output of the command?
A. The backup piece is expired as the new backup is available
B. The backup piece is expired because the operating-system file was not found
C. The backup piece is expired because the retention period for the backup has expired
D. The backup piece is expired because the backup set to which it belongs is not complete
50:
查看下表并检查CROSSCHECK BACKUP命令的输出结果。
哪些语句是正确的关于命令的输出
A. 备份片失效因为新的备份是可用的
B. 备份片失效因为操作系统上文件找不到
C. 备份片失效因为备份保留时间失效
D. 备份片失效因为它所属的备份集不完整
答案:B
CROSSCHECK BACKUP的作用是检查备份的可用性(物理上是否存在),并对失效的备份集打上expired标记
ACD都属于违背备份策略的备份集,需要使用obsolete操作。
参考官方文档:
http://docs.oracle.com/cd/E11882_01/backup.112/e10642/rcmmaint.htm#BRADV8171
wangtong
发表于 2016-10-24 10:22:01
51:
Your database instance is configured with automatic undo management and the UNDO_RETENTION parameter is set to 900 seconds. You executed the following command to enable retention guarantee:
SQL> ALTER TABLESPACE undotbs1 RETENTION GUARANTEE;
What affect would this command have on the database?
A. The extents in the undo tablespace retain data until the next full database backup
B. The extents containing committed undo in the undo tablespace are not overwritten for at least 15 minutes
C. The extents containing committed data in the undo tablespace are not overwritten until the instance is shut down
D. The extents containing committed undo in the undo tablepace are transferred to Flash Recovery Area before being overwritten
51:
你的数据库实例配置UNDO自动管理并且UNDO_RETENTION参数设置为900秒。执行下面的命令启用retention guarantee:
SQL> ALTER TABLESPACE undotbs1 RETENTION GUARANTEE;
这个命令在数据库中会有什么影响?
A. undo表空间中的extent会保留数据直到下次数据库完整备份
B. undo表空间中的包含已提交的undo的extent不会被覆盖在15分钟内
C. undo表空间中的包含已提交的data的extent不会被覆盖直到数据库实例关闭
D. undo表空间中包含已提交的undo的extent会被传输到Flash Recovery Area在被覆盖前
答案:B
因为undo表空间是自动管理的,所以执行上面的命令后,UNDO_RETENTION变成强依赖参数,即使拒绝执行SQL DML操作,也不会发生undo数据覆盖的情况。
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e40402/initparams265.htm#REFRN10225
wangtong
发表于 2016-10-24 10:22:18
52:
You configured the Flash Recovery Area for your database. The database instance has been started in ARCHIVELOG mode and the LOG_ARCHIVE_DEST_1 parameter is not set. What will be the implications on the archiving and the location of archive redo log files?
A. Archiving will be disabled because the destination for the redo log files is missing
B. The database instance will shut down and the error details will be logged in the alert log file
C. Archiving will be enabled and the destination for the archived redo log file will be set to the Flash Recovery Area implicitly
D. Archiving will be enabled and the location for the archive redo log file will be created in the default location $ORACLE_HOME/log
52:
为数据库配置Flash Recovery Area。数据库实例启动于ARCHIVELOG模式并且LOG_ARCHIVE_DEST_1参数没有设置。归档和归档日志的位置会受到什么影响?
A. 归档会被禁用因为归档目的地丢失
B. 数据库实例会关闭并将错误详细记录在alert之日中
C. 归档会启用且归档日志将会设置为Flash Recovery Area
D. 归档会启用且归档日志会默认创建在$ORACLE_HOME/log
答案:C
如果打开归档,并且没有指定归档路径的话,那么默认就是在闪回恢复区
wangtong
发表于 2016-10-24 10:22:36
53:
Which is the correct description of a pinned buffer in the database buffer cache?
A. The buffer is currently being accessed
B. The buffer is empty and has not been used
C. The contents of the buffer have changed and must be flushed to the disk by the DBWn process
D. The buffer is a candidate for immediate aging out and its contents are synchronized with the block contents on the disk
53:
哪些描述是正确的关于数据库buffer cache中的pinned buffer?
A. buffe目前正在被访问
B. buffer是空的,没有被使用
C. buffer的内容被修改且必须通过DBWn进程刷新到磁盘
D. buffer作为即将老化的候选并且内容和磁盘上的内容相同
答案:A
每个buffer都有一个访问方式:pinned 或者free(unpinned)。Buffer固定在cache中以至于内存不会老化当一个用户会话访问的时候。多个会话不能同时修改pinned buffer
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e40540/memory.htm#CNCPT1222
wangtong
发表于 2016-10-24 10:22:58
54:
In which situation would you use static database registration for a listener?
A. When multiple databases are to be registered with the listener
B. When DBAs need to connect remotely to start up the database instance
C. When users need to connect the database instance using the host naming method
D. When the database instance that is to be registered with the listener is configured in shared server mode
54:
在什么情况下你使用数据库静态注册监听?
A. 当多个数据库被注册使用监听
B. 当DBA需要远程启动数据库实例
C. 当用户需要连接数据库实例使用主机名方法
D. 当数据库实例被使用监听注册配置为共享服务模式
答案:B
静态注册可以远程管理数据库,比如数据库的起停,而动态注册必须数据库启动才可以
动态注册为ready从字面的意思理解为准备好,而静态注册为unknow也就是不知道数据库状态
参考官方文档:
http://docs.oracle.com/cd/E11882_01/network.112/e41945/listenercfg.htm#NETAG1154
wangtong
发表于 2016-10-24 10:23:18
55:
While observing the index statistics, you find that an index is highly fragmented, thereby resulting in poor database performance. Which option would you use to reduce fragmentation without affecting the users who are currently using the index?
A. Validate the index structure using the ANALYZE .... INDEX command
B. Rebuild the index using the ALTER INDEX ..... REBUILD ONLINE command
C. Change the block space utilization parameters using the ALTER INDEX command
D. Deallocate the unused space in the index using the ALTER INDEX ... DEALLOCATE UNUSED command
55:
观察索引统计信息,你发现一个索引高度分裂,从而导致数据库性能下降。哪种方法你可以用来减少分裂不影响正在使用索引的用户?
A. 分析索引结构使用ANALYZE……INDEX命令
B. 重建索引使用ALTER INDEX…..REBUILD ONLINE命令
C. 改变块空间利用率使用ALTER INDEX命令
D. 释放未使用的空间索引使用ALTER INDEX……DEALLOCATE UNUSED命令
答案:B
由于频繁的dml,索引就会产生碎片,它的效率会越来越慢,因此就需要重建,
可以使用online关键字在线重建索引,因为重建索引的时候会加锁,假如该关键字后,可以使加锁时间变的很短,从而减少对使用索引用户的影响
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e41084/statements_1010.htm#SQLRF00805
wangtong
发表于 2016-10-24 10:23:53
56:
See the Exhibit to observe the roles assigned to the SL_REP user. Which statement is true about the assignment of the SELECT_CATALOG_ROLE role to the SL_REP user?
A. The user must enable the role explicitly
B. The user can grant the role to other users
C. The user cannot user the role until the DBA enables it explicitly
D. The user can start using the role immediately without any changes
56:
观察下图SL_REP用户分配的角色。哪些语句是正确的关于分给SL_REP用户的SELECT_CATALOG_ROLE角色?
A. 用户必须显式的启用角色
B. 用户可以授予角色给其他的用户
C. 用户不能使用角色直到DBA显式的启用它
D. 用户可以立即使用角色不做任何改变
答案:A
select_catalog_role 是一种角色,题中默认为N,需要重新登录或者显式的set role 来生效,所以选A。
wangtong
发表于 2016-10-24 10:28:57
57:
To make audit information more productive, the DBA executes the following command before starting an audit operations:
SQL>ALTER SYSTEM SET AUDIT_TRAIL=DB,EXTENDED SCOPE=SPFILE;
Which statement is true regarding the audit record generated when auditing starts after restarting the database?
A. It contains only the plan for the SQL statement executed by the user
B. It contains the SQL text executed by the user and the bind variables used with it
C. It contains the plan and statistics associated with the SQL statement executed by the user
D. It contains the plan for the SQL statement executed by the user and the bind variables used with it
57:
为了使审计更生产化,DBA执行下面命令在开始审计操作之前:
SQL>ALTER SYSTEM SET AUDIT_TRAIL=DB,EXTENDED SCOPE=SPFILE;
哪些语句是正确的关于审计记录产生当启动审计在重启数据库后?
A. 只包含用户执行的SQL语句执行计划
B. 包含用户执行的SQL文本和它使用的绑定变量
C. 包含用户执行的执行计划和统计信息相关的SQL语句
D. 包含用户执行的SQL语句执行计划和使用的绑定变量
答案:B
AUDIT_TRAIL值含义如下:
DB:启用审计,信息记录在SYS.AUD$中
OS:启用审计,审计信息保存在操作系统,Oralce建议使用该配置
Db,extended:启用审计,并且记录对应的执行语句
Xml:启用审计,审计信息以xml形式保存在操作系统上
Xml,extended:启用审计,并且包括所有的执行语句
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e40402/initparams017.htm#REFRN10006
wangtong
发表于 2016-10-24 10:30:07
58:
You want to import schema objects of the HR user using Oracle Data Pump from the development database, DEVDB, to the production database, PRODDB. A database link devdb.us.oracle.com is created between PRODDB and DEVDB. You execute the following command on the PRODDB database server:
$ impdp system/manager directory = DB_DATA
dumpfile = schemas.dat
schemas = hr
flashback_time = "TO_TIMESTAMP('25-08-2007 14:35:00', 'DD-MM-YYYY HH24:MI:SS')"
The command fails displaying the following error:
ORA-39001: invalid argument value
ORA-39000: bad dump file specification
ORA-31640: unable to open dump file "/home/oracle/schema/schemas.dat" for read ORA-27037: unable to obtain file status
What would you do to overcome the error?
A. Add the user, SYSTEM, to the schemas option.
B. Add the network_link = devdb.us.oracle.com option.
C. Change the dumpfile option to schema.dat@devdb.us.oracle.com.
D. Replace the schemas option with the network_link = devdb.us.oracle.com
E. Replace the dumpfile option with the network_link = devdb.us.oracle.com
58:
你想导入HR用户使用数据泵从开发数据库DEVDB到生产数据库PRODDB。一个数据库连接devdb.us.oracle.com被创建在PRODDB和DEVDB之间。你执行下面命令在PRODDB数据库服务端:
$ impdp system/manager directory = DB_DATA
dumpfile = schemas.dat
schemas = hr
flashback_time = "TO_TIMESTAMP('25-08-2007 14:35:00', 'DD-MM-YYYY HH24:MI:SS')"
命令报错如下:
ORA-39001: invalid argument value
ORA-39000: bad dump file specification
ORA-31640: unable to open dump file "/home/oracle/schema/schemas.dat" for read ORA-27037: unable to obtain file status
你做什么来解决这个错误?
A. 增加用户SYSTEM在schema选项
B. 增加network_link=devdb.us.oracle.com 选项
C. 改变dumpfile选项为schema.dat@devdb.us.oracle.com
D. 代替schema选项为network_link = devdb.us.oracle.com
E. 代替dumpfile选项为network_link = devdb.us.oracle.com
答案:E
通过database link 导数据需要提供参数 network_link ,这时不会生成 dump file,所以不需要dumpfile 参数。
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e22490/dp_import.htm#SUTIL300
wangtong
发表于 2016-10-24 10:30:23
59:
Which two statements are true about the Automatic Database Diagnostic Monitor (ADDM)? (Choose two.)
A. The ADDM requires at least four AWR snapshots for analysis
B. The ADDM runs after each AWR snapshot is collected automatically by MMON
C. The results of the ADDM analysis are stored in the Automatic Workload Repository (AWR)
D. The ADDM analysis provides only diagnostics information but does not provide recommendations
E. The ADDM calls other advisors if required, but does not provide recommendations about the advisors
59:
哪两句是正确的关于自动数据库诊断监视器(ADDM)?(选择两个)
A. ADDM需要至少四个AWR快照用于分析
B. ADDM运行在MMON自动收集每个AWR快照之后
C. ADDM分析的结果存储在AWR
D. ADDM分析提供诊断信息不提供建议
E. ADDM调用其它advisors如果需要,但是不提供建议
答案:BC
ADDM
每个awr快照被记录后,addm就会自动运行,分析与最后两个快照对应的时段中的数据,addm会主动监视实例
多数情况下,addm会为检测到的问题提供解决方案,addm可以检测到一些常见问题如下
1.cpu瓶颈
2.oracle net 连接管理问题
3.锁的竞争
4.IO问题
5.一些数据库实例内存结构的大小不足
6.过载的sql语句
7.plsql和java运行时间过长
8.检查点负载过高及原因(如日志文件过小)
因此:BC正确
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e41573/diag.htm#PFGRF02602
wangtong
发表于 2016-10-24 10:30:40
60:
Which task would you perform before you run Oracle Universal Installer (OUI) in silent or suppressed mode for an installation?
A. Run the root.sh script.
B. Create the oraInst.loc file.
C. Create the tnsnames.ora file.
D. Run the oraInstRoot.sh script.
60:
哪些任务需要执行在你运行Oracle Universal Installer(OUI)在静默模式或suppressed模式安装之前?
A. 运行root.sh脚本
B. 创建oraInst.loc文件
C. 创建tnsname.ora文件
D. 运行oraInstRoot.sh脚本
答案:B
oraInst.loc是定义inventory路径的,必须咋运行OUI之前创建
root.sh和oraintRoot.sh都是安装的时候执行的
tnsnames.ora是配置网络连接远程的
参考官方文档:
http://docs.oracle.com/cd/E11882_01/gateways.112/e12076/responsefiles.htm#IVACU592
wangtong
发表于 2016-10-26 11:26:38
61:
You are working on an instance started using the SPFILE. You want to move the Flash Recovery Area of your database to a new location. You want the Flashback log files to be stored in the new location. Given below are the steps to accomplish the task in random order:
1) Shut down the instance.
2) Change the value of the DB_RECOVERY_FILE_DEST initialization parameter to a new value.
3) Execute the ALTER DATABASE FLASHBACK OFF command.
4) Start up the instance and mount the database.
5) Execute the ALTER DATABASE FLASHBACK ON command.
6) Open the database.
Select the correct order in which these tasks need to be performed.
A. 2, 1, 4, 3, 5, 6
B. 1, 4, 3, 2, 6, 5
C. 1, 4, 2, 6, 3, 5
D. 3, 2, 1, 4, 5, 6
61:
你正在一个使用spfile启动的数据库实例工作。你想移动Flash Recovery Area到一个新的位置。你想Flashback 日志存储在新的位置。下面是完成这项任务的随机排序步骤:
1) 关闭实例
2) 改变参数DB_RECOVERY_FILE_DEST的值为新的值
3) 执行ALTER DATABASE FLASHBACK OFF命令
4) 启动数据库实例并mount数据库
5) 执行ALTER DATABASE FLASHBACK ON命令
6) 打开数据库
选择正确的执行顺序
A. 2, 1, 4, 3, 5, 6
B. 1, 4, 3, 2, 6, 5
C. 1, 4, 2, 6, 3, 5
D. 3, 2, 1, 4, 5, 6
答案:A
本题是想考查更换Flash Recovery Area的位置
参考官方文档:
http://docs.oracle.com/cd/E11882_01/backup.112/e10642/rcmmaint.htm#BRADV89618
wangtong
发表于 2016-10-26 11:26:59
62:
You are in the middle of a transaction updating a very important table. The machine on which a database was running reboots because of power outage. This caused a database instance failure.
Which statement is true in this situation?
A. The online redo log files and archived redo log files are required to accomplish the recovery
B. The uncommitted transaction will be committed at the next startup of the database instance
C. The uncommitted transaction is rolled back automatically at the next opening of the database
D. The DBA has to perform the recovery on the database to recover the uncommitted transaction
62:
你处于一个正在更新一个非常重要的表的事务中。数据库正在运行的机器因为断电重启。这导致数据库实例故障。哪些语句是正确的在这种情况?
A. 完成恢复需要联机重做日志和归档日志
B. 下一次数据库实例启动的时候会提交未提交的事务
C. 下一次数据库打开会自动回滚未提交的事务
D. DBA执行数据库恢复去恢复未提交的事务
答案:C
完成恢复只需要联机重做日志,不需要归档日志,所以A错
下一次启动实例的时候会将位提交的事务回滚而不是提交,B错,C对
实例恢复由SMON自动执行,而不是DBA控制,D错
wangtong
发表于 2016-10-26 11:27:30
63:
View the Exhibit to examine the output produced by the following query at three different times since the database instance started and has experienced workloads of different capacities:
SQL> SELECT substr(component, 0, 10) COMP, current_size CS, user_specified_size US FROM v$memory_dynamic_components WHERE current_size!=0;
What do you infer from this?
A. The database instance is running with manual PGA management.
B. The database instance is running with manual shared memory management.
C. The database instance has the MEMORY_TARGET value set to a nonzero value.
D. All sessions are connected to the database instance in dedicated mode, and no RMAN or parallel query operations have been performed.
63:
查看下图检查存储过程输出结果,自从数据库实例启动并经历不同的工作负载在三个不同的时间:
SQL> SELECT substr(component, 0, 10) COMP, current_size CS, user_specified_size US
FROM v$memory_dynamic_components WHERE current_size!=0;
你能推断出什么?
A. 数据库实例正在运行,使用手动管理PGA
B. 数据库实例正在运行,使用手动管理共享内存
C. 数据库实例设置MEMORY_TARGET为非0值
D. 所有的会话连接数据库实例为专用模式,没有RMAN或者并行查询操作执行
答案:C
动态性能视图V$MEMORY_DYNAMIC_COMPONENTS显示所有动态优化的内存组件的当前大小,其中包括SGA 和实例PGA 的总大小。三次启动的SGA的各个组件大小都一样,是动态变化的,PGA也是动态变化的,所以此数据库是处于自动内存管理即AMM,也即是说MEMORY_TARGET设定为非零值
wangtong
发表于 2016-10-26 11:28:44
64:
Your database instance is started using the server parameter file (SPFILE). You executed a command to change the value of the LOG_BUFFER initialization parameter:
ALTER SYSTEM SET LOG_BUFFER=32M SCOPE=BOTH;
What would be the outcome of this command?
A. The command succeeds only if Automatic Memory Management is not enabled.
B. The command succeeds, but you need to restart the database for changes to take effect.
C. The command returns an error because the size of the redo log buffer cannot be changed dynamically.
D. The parameter value is changed and it comes into effect as soon as space becomes available in the System Global Area (SGA).
64:
你的数据库实例启动使用SPFILE。你执行一个命令改变LOG_BUFFER的值:
ALTER SYSTEM SET LOG_BUFFER=32M SCOPE=BOTH;
这个命令的输出结果是什么?
A. 命令执行成功只有自动内存管理没有启用的时候
B. 命令执行成功,但是你需要重启数据库来生效
C. 命令返回一个错误因为redo log buffer不能动态修改
D. 参数值被修改并且会立即生效只要SGA中有可用的空间
答案:C
LOG_BUFFER为静态参数,故只能使用SCOPE=spfile,重启后生效
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e25494/create.htm#ADMIN11119
wangtong
发表于 2016-10-26 11:29:24
65:
The database instance is currently using SPFILE. View the Exhibit and examine the error that you received while running the DB Structure Integrity check. Given below are the steps to recover from the error in random order:
1. Shut down the instance, if not already done.
2. Copy one of the remaining control files to a new location.
3. Change the value of the CONTROL_FILES initialization parameter to correspond to the new location of the control files.
4. Start up the database instance to the NOMOUNT stage.
5. Recover the database to the point of failure of the control file.
6. Open the database.
Identify the correct sequence of steps?
A. 1, 2, 4, 3, 5, 6
B. 2, 4, 3, 5, 6; 1 not required
C. 4, 5, 6, 2, 3; 1 not required
D. 5, 2, 3, 4; 1 and 6 not required
65:
数据库实例正在使用SPFILE。查看下表并检查运行DB结构完整性检查时发生的错误。下面给出随机步骤恢复错误:
1. 关闭实例,如果尚未完成
2. 拷贝一个冗余控制文件到新的位置
3. 改变CONTROL_FILES初始参数的值和新位置一致
4. 启动数据库实例到NOMOUNT阶段
5. 恢复数据库到控制文件的故障点
6. 打开数据库
鉴别正确的步骤顺序?
A. 1, 2, 4, 3, 5, 6
B. 2, 4, 3, 5, 6; 1 不需要
C. 4, 5, 6, 2, 3; 1不需要
D. 5, 2, 3, 4; 1 和 6不需要
答案:A
本题考查的是使用RMAN恢复控制文件
参考官方文档:
http://docs.oracle.com/cd/E11882_01/backup.112/e10642/rcmadvre.htm#BRADV154
wangtong
发表于 2016-10-26 12:45:17
本帖最后由 wangtong 于 2017-3-2 17:37 编辑
66:
You are working on a new Oracle Database 11g server, where only the software is installed and no database is created. You plan to create a database on this server using the Database Configuration Assistant (DBCA). Some of the requirements set for your database creation task are:
1. Configure the database to operate in shared server mode.
2. Disable automatic maintenance tasks such as optimizer statistics collection.
3. Configure a naming method to help the remote user connect to the database instance.
4. Use Automatic Storage Management (ASM) for storing the database files.
5. Configure daily database backup to flash recovery area.
6. Configure Enterprise Manager Database Control to manage the database.
Which of these requirements can be met while creating the database?
A. 4 and 6
B. 2, 3, 4, and 6
C. 1, 2, 4, 5, and 6
D. 1, 2, 3, 4, 5, and 6
66:
你正在一个新的Oracle 11g数据库工作,只安装了软件没有创建数据库。你计划使用DBCA创建一个数据库在这个服务器上。
一些数据库创建需要的设置任务是:
1. 配置数据库为共享服务器模式
2. 禁用自动维护任务例如优化器统计信息收集
3. 配置一个命名方法帮助远程用户连接数据库实例
4. 使用自动储存管理(ASM)存储数据文件
5. 配置日常数据库备份到FRA
6. 配置企业管理控制台管理数据库
哪些要求可以被满足当创建数据库的时候?
A. 4 和 6
B. 2, 3, 4, 和 6
C. 1, 2, 4, 5, 和 6
D. 1, 2, 3, 4, 5, 和 6
答案:C
DBCA创建数据库如下:
1.Database Configuration Assistant:Welcome
2.Database Configuration Assistant,Step 1 of 13:Operations 选择Create a Database
3.Database Configuration Assistant,Step 2 of 13:Database Templates 选择General Purpose or Transaction Processing
4.Database Configuration Assistant,Step 3 of 13:Database Identification 填写Global Database Name和SID
5.Database Configuration Assistant,Step 4 of 13:Management Options 选择Enterprise Manager和Automatic Maintenance Tasks
6.Database Configuration Assistant,Step 5 of 13:Database Credentials 填写密码
7.Database Configuration Assistant,Step 6 of 13:Network Configuration 选择监听器
8.Database Configuration Assistant,Step 7 of 13:Database File Locations 选择ASM
9.Database Configuration Assistant,Step 8 of 13:Recovery Configuration快速恢复区指定
10.Database Configuration Assistant,Step 9 of 13:Database Content 勾选Sample Schemas
11.Database Configuration Assistant,Step 10 of 13:Initialization Parameters 包括Memory,Sizing,Character Sets,Connection
wangtong
发表于 2016-10-26 12:45:41
67:
Examine the following output:
SQL> SELECT index_name,status FROM dba_indexes WHERE status='UNUSABLE';
INDEX_NAME STATUS
--------------- ---------------
EIND UNUSABLE
Which two statements about the above index are true? (Choose two.)
A. It is ignored by the query optimizer.
B. It is not used while the index is being rebuilt.
C. The index cannot be rebuilt, and has to be re-created.
D. The index is automatically rebuilt when used the next time.
67:
检查下面的输出:
SQL> SELECT index_name,status FROM dba_indexes WHERE status='UNUSABLE';
INDEX_NAME STATUS
--------------- ---------------
EIND UNUSABLE
哪两句关于索引的描述是正确的?(选择两个)
A. 它被查询优化器忽略
B. 它不用被使用当重建的时候
C. 索引不能被rebuilt必须重新create
D. 索引会自动rebuilt当下次使用的时候
答案:AB
当你创建一个索引为UNUSABLE状态,它会被查询优化器忽略并且不会被DML维护。一个UNUSABLE索引必须被rebuilt或删除后create,在它被使用之前。如果索引被分区,所有的分区索引会被标记为UNUSABLE。
在Oracle 数据库11g Release 2,当数据库创建一个unusable 索引的时候,不会创建索引段。
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e25494/indexes.htm#ADMIN13282
wangtong
发表于 2016-10-26 12:46:05
68:
In a system, large online transaction processing (OLTP) jobs run during the daytime that require a large database buffer cache. In the night, the system supports batch jobs that require a higher value to be set for the large pool. You must simultaneously configure the memory components to accommodate the peak requirement.
What would you do to automate this configuration for the memory components with change in mode of working?
A. Set the SGA_TARGET initialization parameter to zero.
B. Set the PRE_PAGE_SGA initialization parameter to TRUE.
C. Set the MEMORY_MAX_TARGET initialization parameter to zero.
D. Set the SGA_TARGET initialization parameter to a nonzero value.
68:
在一个大型联机事务处理(OLTP)系统在白天需要巨大的数据库buffer cache。在晚上,系统支持批量任务需要设置large pool为很大的值。你必须配置内存组件同时适应峰值要求。
你会怎么做来自动化配置内存组件适用模式变化的工作?
A. 设置SGA_TARGET初始值为0
B. 设置PRE_PAGE_SGA初始值为TRUE
C. 设置MEMORY_MAX_TARGET初始值为0
D. 设置SGA_TARGET初始值为非0值
答案:D
因为白天需要大的BUFFER CACHE,晚上需要大的LARGE POOL,所以可以启动ASMM管理。
启动ASMM,需要:
1.除了sga_target,sga_max_size,lock_sga,pre_page_sga需要静态调整外,其他都可以动态调整
2.启用方法是需要将sga_target 设置为非0,同时将statistics_level设置为typical或者all
3.如果使用了自动共享内存管理,下面这些缓存区就不需要在进行设置了,他们会自动设置为0
i.db_cache_size
ii.shared_pool_size
iii.large_pool_size
iv.java_pool_size
v.streams_pool
4.尽管使用了assm,还是可以设置缓存区大小的,设置后表示的是该缓存区的下限值,即orale任何时候该缓存区都应该不小于这个值,至少预留这么大的空间
wangtong
发表于 2016-10-26 12:46:29
69:
You have executed this command to change the size of the database buffer cache:
SQL> ALTER SYSTEM SET DB_CACHE_SIZE=2516582;
System altered.
To verify the change in size, you executed this command:
SQL> SHOW PARAMETER DB_CACHE_SIZE
NAME TYPE VALUE
-------------- ------------ ------------
db_cache_size big integer 4194304
Why is the value set to 4194304 and not to 2516582?
A. Because 4194304 is the granule size
B. Because 4194304 is the standard block size
C. Because 4194304 is the largest nonstandard block size defined in the database
D. Because 4194304 is the total size of data already available in the database buffer cache
69:
你执行下面命令去改变数据库buffer cache的值:
SQL> ALTER SYSTEM SET DB_CACHE_SIZE=2516582;
System altered.
为了验证大小的修改,执行下面命令:
SQL> SHOW PARAMETER DB_CACHE_SIZE
NAME TYPE VALUE
-------------- ------------ ------------
db_cache_size big integer 4194304
为什么值设置为4194304,而不是2516582?
A. 因为4194304是粒度大小
B. 因为4194304是标准块大小
C. 因为4194304是数据库定义中最大的非标准块大小
D. 因为4194304是数据库buffer cache已使用的数据总大小
答案:A
如果指定的大小不是粒度的整倍数,则约等于到整倍数,例如粒度为4M,指定DB_CACHE为10M,则实际上为12M
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e25494/memory.htm#BABGEGEH
wangtong
发表于 2016-10-26 12:46:47
70:
Identify two situations in which the block header grows in a data block. (Choose two.)
A. When row directories need more row entries
B. When there is row migration in the data block
C. When there is an increase in the PCTFREE value for the data block
D. When more transaction slots are required than are initially configured
70:
确定数据块块头增长的两种情况(选择两个)
A. 当行目录需要更多的行信息
B. 当数据块中发生行迁移
C. 当数据块中的PCTFREE的值增加
D. 当更多的事务槽需要比最初设置
答案:AD
块头:块头包含段类型(如表或索引)、数据块地址、表目录、行目录和事务处理插槽。每个插槽的大小约为23 字节,修改块中的行时会使用这些插槽。块头自上而下进行增长。
• 行数据:这是块中行的实际数据。行数据空间自下而上进行增长。
• 空闲空间:空闲空间位于块的中部,允许头和行数据空间在必要时进行增长。当插入新行或用更大的值更新现有行的列时,行数据会占用空闲空间。
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e40540/logical.htm#CNCPT004
wangtong
发表于 2016-10-27 16:48:26
71:
You are installing Oracle Database 11g on your server. During the installation Oracle Universal Installer (OUI) prompts you to enter the path of the inventory directory and also prompts you to specify an operating system group name. Which statement is true in this case?
A. The ORACLE_BASE parameter is not set.
B. The installation is being performed by the root user.
C. The operating system group that will be specified should have root user as its member.
D. The installation is being performed without the "Create Starter Database" option selected.
E. The operating system group that will be specified must have permission to write to the inventory directory.
71:
你正在安装Oracle 数据库 11g在你的服务器上。在安装期间,Oracle Universal Installer(OUI)提示你输入产品目录路径并提示你指定一个操作系统组名。哪些语句是正确的在这种情况下?
A. ORACLE_BASE参数没设置
B. 使用root用户执行安装
C. 被指定的操作系统组应该有root用户作为成员
D. 没有使用选项"Create Starter Database"执行安装
E. 被指定的操作系统组必须有权限写产品目录
答案:E
wangtong
发表于 2016-10-27 16:49:04
72:
View the Exhibit. You want to create a tablespace to contain objects with block size 16 KB. But while configuring the storage you find that the block size that you can provide is only 8 KB. Which configuration could have enabled the block selection of 16 KB?
A. Choosing the extent allocation type to uniform
B. Choosing the Segment Space Management option to manual
C. Setting autoextension on for the data file mentioned for the tablespace
D. Setting the DB_16K_CACHE_SIZE parameter for the database instance to a nonzero value
72:
查看下表。你想创建一个表空间包含16KB块大小的对象。但是当配置存储的时候你发现你只能提供×KB块大小。哪些配置可以让你选择使用16KB?
A. 选择extent分配类型为uniform
B. 选择段空间管理方式为手动
C. 设置表空间涉及的数据文件为自动扩展
D. 设置数据库实例参数DB_16K_CACHE_SIZE为非零值
答案:D
1.9i之后可以使用多种块大小,首先使用一个标准的数据块,然后最多可以定义4种其他的数据块,值为2的n次方,范围是2~32(这里也就5种)
2.使用其他块大小的时候,必须首先设置 db_nk_cache_size 的大小
SQL> show parameter k_cache_size
NAME TYPE VALUE
------------------ ----------- ------
db_16k_cache_size big integer 0
db_2k_cache_size big integer 0
db_32k_cache_size big integer 0
db_4k_cache_size big integer 0
db_8k_cache_size big integer 0
首先应该设置这里对应的值,这里需要注意的是与数据库块大小相同的不能设置
create tablespace cache_size datafile'cache_size_001.dbf' size 16M BLOCKSIZE 16K; --这里的16k必须先设置db_16k_cache_size
3.标准数据库大小用于系统表空间和临时表空间
4.数据块的内容和参数
i.块头
存储数据块的地址、表目录、行目录和事务槽,头部从上往下增长
ii.数据区
位于数据块的底部,当插入行的时候从下向上增长
iii.空闲区
位于中间,最初始是连续的,当删除和插入后导致碎片化,smon会进行合并空闲区的操作
5.手工数据块的管理
i.插入操作的时候,oracle将保留数据块15%的空闲空间,为将来的更新做准备
ii.当空闲区小于15%的时候,oracle将该数据从空闲队列(freelists)中去掉
iii.如果删除或修改造成了数据行的缩小,虽然大于了15%,但是使用的空间大于30,因此还是不能插入
iv.只有当小于30(pctused),该数据块才可以重新放入空闲队列中
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e25494/memory.htm#ADMIN11218
wangtong
发表于 2016-10-27 16:49:46
73:
You are installing Oracle Database 11g on a machine. When you run the installer, the Universal Installer (OUI) shows the message that says one of the product-specific prerequisite checks has failed:
Checking available swap space requirements ...
Expected result: 1512MB
Actual Result: 1018MB
Check complete.
The overall result of this check is: Failed <<<< Problem: The system does not have the required swap space.
What happens to the installation in this situation?
A. It can be continued.
B. It resizes the swap space automatically when you proceed further.
C. It can be continued, but the instance cannot be started without increasing the swap space.
D. It shows a message saying one or more prerequisite checks have failed and the installation cannot proceed.
73:
你正在机器上安装Oracle Database 11g。当你运行安装,Universal Installer (OUI)显示消息一项检查没有通过:
Checking available swap space requirements ...
Expected result: 1512MB
Actual Result: 1018MB
Check complete.
The overall result of this check is: Failed <<<< Problem: The system does not have the required swap space.
这种情况下安装发生了什么问题?
A. 可以继续安装
B. 进一步执行会自动调整SWAP空间大小
C. 可以继续,但是实例不能启动,如果不增加swap空间
D. 消息显示一个或多个先决条件检查失败,安装无法继续进行
答案:A
1512M是期望值,不是必须达到的值,一般主要达到150M,就可以安装,选择A
wangtong
发表于 2016-10-27 16:50:18
74:
Which two statements about the background process of the database writer are true? (Choose two.)
A. It is possible to have multiple database writers in an Oracle instance.
B. It writes dirty buffers, if any, to data files whenever a checkpoint occurs.
C. It writes dirty buffers, if any, to data files whenever a transaction commits.
D. It writes dirty buffers, if any, to data files before the log writer (LGWR) writes.
74:
哪两个语句是正确的关于数据库写的后台进程是正确的?(选择两个)
A. 可能有多个数据库写在一个数据库实例中
B. 如果发生检查点时,它会写脏缓冲区到数据文件
C. 如果发生事务提交,它会写脏缓冲区到数据文件
D. 在发生LGWR之前,它会写脏缓冲区到数据文件
答案:AB
虽然对于大多数系统来说,一个数据库写进程(DBW0) 已经足够,但如果系统需要频繁修改数据,则可以配置附加进程(DBW1到DBW9以及DBWa到DBWj)以改进写性能(A正确,可以有很多个dbwr进程)。
DBWR触发条件
1. 产生检查点
2. 脏数据缓冲区达到阀值 默认 10%
3.扫描整个data buffer没有空闲data buffer 中包含脏的和未脏的优先写脏数据列表 再写未脏块
4. timeout 超时,如果DBWR没事做 会被每三秒唤醒一次去巡检 写不写不一定
5. 表级别的truncate 或 drop 也会触发数据写
6. 修改表空间的 read only
7. 做表空间的offline (离线)
8. 热备份 begin backup 命令
LGWR 触发条件:
1.用户进程提交事务处理时
2.重做日志缓冲区的三分之一已满时
3.重做日志缓冲区达到1M的redo条目
4.在DBWn进程将经过修改的缓冲区写入磁盘(如果需要)之前
5.每隔3 秒
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e40540/process.htm#CNCPT9840
wangtong
发表于 2016-10-27 16:50:45
75:
The TRANS_SUMMARY table contains product-wise transaction details that get updated with every transaction in the system. Each row has cumulative transaction details of a single product and every product is identified by a product code, which is the primary key. As part of the archival process, the company wants to transfer the rows in the TRANS_SUMMARY table to the TRANS_SUMMARY_DUP table at the end of every quarter of the year. Along with existing products, the company deals with many new products during every quarter. Which method is best suited for this quarterly data transfer?
A. Using the MERGE command
B. Using the SQL*Loader utility
C. Using the correlated UPDATE command
D. Using the INSERT command to perform bulk operation
75:
TRANS_SUMMARY表包含生产方面的事务细节如系统中的每笔交易。每一行累积记录单个产品的交易细节并且每个产品使用产品码也就是主键来鉴别。作为归档的一部分过程,公司想在每年的季度末转移TRANS_SUMMARY表的行到TRANS_SUMMARY_DUP表。随同现有的产品,公司在每季度期间交易很多新产品。哪种方法是最适合这个季度数据传输的?
A. 使用MERGE命令
B. 使用SQL*Load功能
C. 使用相关的UPDATE命令
D. 使用INSERT命令执行批量操作
答案:A
使用MERGE命令可在一个命令中执行UPDATE 和INSERT 。可将一个源中的数据合并到另一个源,因而可选择插入新行和更新特定列(如果行已经存在)。
这道题的意思是将TRANS_SUMMARY里的数据合并到TRANS_SUMMARY_DUP表里,如果TRANS_SUMMARY_DUP有存在的产品,则保留,如果是新产品,则插入。
wangtong
发表于 2016-10-27 16:51:30
76:
Which two statements are true regarding a PL/SQL package body? (Choose two.)
A. It cannot be created without a package specification.
B. It cannot invoke subprograms defined in other packages.
C. It can contain only the subprograms defined in the package specification.
D. It can be changed and recompiled without making the package specification invalid.
76:
哪两句关于PL/SQL包主体的描述是正确的?
A. 可以被创建不指定包
B. 不能调用其他包的子程序
C. 只能包含指定的包中定于的子程序
D. 没有标记指定的包为无效的时候可以被修改和重新编译
答案:AD
程序包体:
• 与程序包说明是分开的。因此,可以更改并重新编译程序包体代码,此时不会将与程序包说明相关的其它对象标记为无效。
• 包含程序包说明中定义的子程序的代码。这是负责完成工作的部分。程序包说明表明了如何调用程序包中的子程序;程序包体是代码段。
• 只有在编译了程序包说明之后才能编译程序包体。可以在没有程序包体的情况下创建程序包说明,但不能在没有程序包说明的情况下创建程序包体。
• 通过包装可隐藏代码明细。包装是一个可打乱PL/SQL 源代码的独立程序,所以可不暴露源代码的情况下传送PL/SQL 应用程序。
A,没有包装说明它不能创建。正确。只有在编译了程序包说明之后才能编译程序包体。可以在没有程序包体的情况下创建程序包说明,但不能在没有程序包说明的情况下创建程序包体。
B,它不能调用其他包中定义的子程序。错误,可以调用。
C,它只能包含包说明中定义的子程序。错误,可以调用不在包装包说明的子程序。
D,它可以改变和重新编译,而不使包装规格无效。正确。与程序包说明是分开的。因此,可以更改并重新编译程序包体代码,此时不会将与程序包说明相关的其它对象标记为无效。
wangtong
发表于 2016-10-27 16:51:45
77:
In your database instance, the user sessions are connected to the database server from the remote machines. You want to achieve the following for these users:
1. The user account must be locked after four unsuccessful login attempts.
2. The user must be prompted to change the password at regular intervals.
3. The user may not have more than three simultaneous sessions.
4. The user session must automatically be logged off if more than 10 minutes elapsed time used.
How would you accomplish the above?
A. By assigning profiles for the users
B. By implementing Fine-Grained Auditing (FGA)
C. By granting a secure application role to the users
D. By implementing the Database Resource Manager plan
77:
在你的数据库实例中,用户会话从远程机器连接数据库服务器。你想这些用户达到下面:
1. 用户帐户必须锁定在四次尝试登录失败之后
2. 用户必须被提示定期更改密码
3. 用户不能有超过三个并发会话
4. 用户必须自动注销如果超过10分钟运行时间
你将如何完成上述所示?
A. 通过指定用户profile
B. 通过实行Fine-Grained Auditing (FGA)
C. 通过授予一个安全的应用角色给用户
D. 通过实行Database Resource Manager plan
答案:A
可以通过配置profile来达到限制上面的目标
SQL> select * from dba_profiles where profile='DEFAULT';
PROFILE RESOURCE_NAME RESOURCE LIMIT
------------------------------ -------------------------------- -------- ----------------------------------------
DEFAULT COMPOSITE_LIMIT KERNEL UNLIMITED
DEFAULT SESSIONS_PER_USER KERNEL UNLIMITED
DEFAULT CPU_PER_SESSION KERNEL UNLIMITED
DEFAULT CPU_PER_CALL KERNEL UNLIMITED
DEFAULT LOGICAL_READS_PER_SESSION KERNEL UNLIMITED
DEFAULT LOGICAL_READS_PER_CALL KERNEL UNLIMITED
DEFAULT IDLE_TIME KERNEL UNLIMITED
DEFAULT CONNECT_TIME KERNEL UNLIMITED
DEFAULT PRIVATE_SGA KERNEL UNLIMITED
DEFAULT FAILED_LOGIN_ATTEMPTS PASSWORD 10
DEFAULT PASSWORD_LIFE_TIME PASSWORD 180
DEFAULT PASSWORD_REUSE_TIME PASSWORD UNLIMITED
DEFAULT PASSWORD_REUSE_MAX PASSWORD UNLIMITED
DEFAULT PASSWORD_VERIFY_FUNCTION PASSWORD NULL
DEFAULT PASSWORD_LOCK_TIME PASSWORD 1
DEFAULT PASSWORD_GRACE_TIME PASSWORD 7
16 rows selected.
wangtong
发表于 2016-10-27 16:52:03
78:
Observe the information in the columns:
1. The SGA
2. The cursor state
3. User-session data
4. The stack space
a. Text and parsed forms of all SQL statements
b. Run-time memory values for the SQL statement, such as rows retrieved
c. Security and resource usage information
d. Local variables for the process
Which option has the correct match between the memory areas and their contents?
A. 1-c, 2-b, 3-d, 4-a
B. 1-b, 2-c, 3-d, 4-a
C. 1-a, 2-b, 3-c, 4-d
D. 1-a, 2-b, 3-d, 4-c
78:
观察列中的信息:
1. SGA
2. 游标状态
3. 用户会话数据
4. Stack space
a. 所有SQL语句的文本和解析形式
b. SQL语句的运行时间内存值,例如行检索
c. 安全性和资源使用信息
d. 程序的本地变量
哪个选项是正确的关于内存区域和他们的解释?
A. 1-c, 2-b, 3-d, 4-a
B. 1-b, 2-c, 3-d, 4-a
C. 1-a, 2-b, 3-c, 4-d
D. 1-a, 2-b, 3-d, 4-c
答案:C
本题主要是考察一些概念问题
wangtong
发表于 2016-10-27 16:52:29
79:
You are using Enterprise Manager to schedule backups for your database. Which type of script would be generated by the backup scheduler?
A. XML script
B. PL/SQL script
C. Operating system script
D. Recovery Manager (RMAN) script
79:
你正在使用Enterprise Manager调度备份你的数据库。哪种类型的脚本会产生通过备份调度?
A. XML脚本
B. PL/SQL脚本
C. 操作系统脚本
D. RMAN脚本
答案:D
如果你启用自动备份,Oracle Enterprise Manager调度一个日常备份job使用RMAN备份所有的数据文件到FRA上。
参考官方文档:
http://docs.oracle.com/cd/E11882_01/install.112/e47689/install_overview.htm#LADBI1073
wangtong
发表于 2016-10-27 16:52:56
80:
Note the following functionalities of various background processes:
1. Record the checkpoint information in data file headers.
2. Perform recovery at instance startup.
3. Cleanup unused temporary segments.
4. Free the resources used by a user process when it fails.
5. Dynamically register database services with listeners.
6. Monitor sessions for idle session timeout.
Which option has the correct functionalities listed for a background process?
A. Archiver Process (ARCn): 1, 2, 5
B. System Monitor Process (SMON): 1, 4, 5
C. Process Monitor Process (PMON): 4, 5, 6
D. Database Writer Process (DBWn): 1, 3, 4
80:
注意下面各种各样的后台进程的功能:
1. 记录检查点信息在数据文件头
2. 执行实例恢复在启动的时候
3. 清楚没使用的临时段
4. 用户进程故障时释放用户使用的资源
5. 使用监听动态注册数据库服务
6. 为空闲会话超时监视会话
哪个选项是正确的列出的后台进程和它的功能?
A. Archiver Process (ARCn): 1, 2, 5
B. System Monitor Process (SMON): 1, 4, 5
C. Process Monitor Process (PMON): 4, 5, 6
D. Database Writer Process (DBWn): 1, 3, 4
答案:C
一、SMON:系统监控进程
1.主要是已经提交的数据但是还没有进行写入数据文件给断电了,重启的时候,smon就会进行恢复
a.执行前滚,将已经写入重做日志文件但是还没有写入到数据文件中的数据(使用scn号码来识别提交记录的)
b.打开数据库
c.回滚没有提交的事务
2.还可以进行磁盘空间维护工作
a.回收或者合并数据文件中相连的空闲区
b.释放临时段
二、PMON:进程监督进程
1.当某个进程崩溃,PMON将负责进行如下的清理工作
a.回滚用户当前事务
b.释放用户所加的所有表一级和行一级的锁
c.释放用户所有的其他资源等
三、ARCn:归档日志进程
1.当一组重做日志文件写满后,会写另外一组,当最后一组写满后会在写第一组,叫做日志切换
2.如果没有开归档,那么覆盖后就无法进行恢复了
3.如果开了归档,那么就会使用arch进程进行写入归档日志文件中,oracle会确保在一组重做日志的归档操作完成之前不会重新使用该组日志
四、DBWn:数据库写进程
1.11g之前只可以有0~9,10个进程,11g之后可以有36个,0~9和a~z,通过 db_writer_processes 来设置个数的,如果启动的时候没有说明个数
那么是由cpu的个数来决定的该参数的
2.当以下情况发生时,DBWR会将高速缓冲区中的数据写入到数据文件中
a.当脏缓冲区的数量超过了所设定的限额
b.所设定的时间间隔已到
c.有进程需要高速缓冲区,但是没有空闲的高速缓冲区空间时候
d.校验(检查点)发生时
e.某个表被删除或者截断(truncate,drop)
f.某个表空间被设置为只读
g.表空间进行联机备份时
h.表空间被设置为脱机时
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e40540/process.htm#CNCPT9840
wangtong
发表于 2016-10-28 16:42:28
81:
Which statement is true about a whole consistent database backup on a database running in ARCHIVELOG mode?
A. The backup will consist of used data blocks only.
B. The database must be shut down to accomplish the backup.
C. The backup can be accomplished without shutting down the database.
D. The backup will contain all database files that have never been backed up.
81:
哪些语句是正确的关于运行在ARCHIVELOG模式下的一致性数据库备份?
A. 只备份使用过的数据块
B. 数据库必须shutdown来完成备份
C. 备份可以在不shutdown数据库的情况下完成
D. 备份将包含所有的未备份过的数据文件
答案:B
一致性备份必须在数据库正常关闭的情况下进行,这个时候redo,数据文件和控制文件的scn都是一致的
参考官方文档:
http://docs.oracle.com/cd/E11882_01/backup.112/e10642/rcmcncpt.htm#BRADV99964
wangtong
发表于 2016-10-28 16:43:11
82:
Which statement is true about the UNDO_RETENTION parameter when retention guarantee is not enabled?
A. It is the time period after which the undo data becomes obsolete.
B. It is the time period after which the committed undo data would be transferred to a temporary tablespace.
C. It is the minimum time period up to which the committed undo data would be retained if free undo space is available.
D. It is the time period after which the undo data is transferred to the Flash Recovery Area to provide read consistency.
82:
哪句是正确的关于UNDO_RETENTION参数在retention guarantee没启用的时候?
A. 它是undo数据变得失效之后的时间
B. 它是提交的undo数据被传输到临时表空间之后的时间
C. 它是undo空间可用的情况下保留提交的undo数据的最小时间
D. 它是undo数据传输到快速闪回区用来提高读一致性所需的时间
答案:C
当 retention guarantee 没有设置时,即undo数据 不强制保留UNDO_RETENTION 所设置的时间内,如果是undo表空间是自动增长,即在足够的空闲空间下,则可能会保留到UNDO_RETENTION 所设置的时间。如果undo表空间是固定的,则UNDO_RETENTION 可能会被忽略,undo数据可能被覆盖。
wangtong
发表于 2016-10-28 16:43:30
83:
You have a large amount of historical data in a flat file. Some analysts in your organization need to query this data in the file. The file is too large to load the data in it into your current database. Which is the most effective method to access this data in your database?
A. Use the database link.
B. Use the SQL*Loader utility.
C. Use the Oracle Data Pump utility.
D. Create an external table and leave the data in the flat file.
83:
你有大量的历史数据在平面文件中。在你的公司中一些分析师需要查询这个文件中的数据。文件太大对你目前的数据库来说。哪种方法是最有效的去访问数据?
A. 使用database link
B. 使用SQL*Load功能
C. 使用Oracle Data Pump功能
D. 创建一个外部表并保留数据在平面文件中
答案:D
因为题目中提到文件过大,不能导入到数据库中,故排除BC,又因为数据存在平面文件中,不是数据库文件,故A也不可行。答案选择D,使用外部表来访问
外部表,参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e22490/et_concepts.htm#SUTIL011
wangtong
发表于 2016-10-28 16:43:49
84:
Which statements are true regarding the creation of an incident package file by using the EM Workbench Support? (Choose all that apply.)
A. You can add SQL test cases to the incident package.
B. You can add or remove the trace files to the package.
C. You cannot create an incremental incident package when the physical files are purged from the ADR.
D. You can create the incremental incident package ZIP file for new or modified diagnostic information for the incident package already created.
84:
哪些语句是正确的关于使用EM Workbench Support创建一个事件包文件?(选择所有正确的)
A. 你可以在事件包添加SQL测试用例
B. 你可以在事件包添加或移除追踪文件
C. 你不能创建一个增量事件包当物理文件从ADR删除
D. 你可以创建增量事件包压缩文件为新的或修改事件包已经创建的诊断信息。
答案:ABD
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e25494/diag.htm#CHDFBEAE
wangtong
发表于 2016-10-28 16:44:15
85:
You are managing an Oracle Database 11g database. You want to ensure the recovery of the database to the point of failure. Which configuration will you do to accomplish the task?
A. Multiplex all database files.
B. Configure the Flash Recovery Area.
C. Configure the database instance for ARCHIVELOG mode.
D. Configure the FAST_START_MTTR_TARGET initialization parameter.
85:
你正在管理一个Oracle Database 11g数据库。你想确保数据库的时间点恢复。哪些配置你需要做来完成这个任务?
A. 多路复用所有的数据文件
B. 配置Flash Recovery Area
C. 配置数据库实例为ARCHIVELOG模式
D. 配置FAST_START_MTTR_TARGET参数
答案:C
指定时间点恢复,需要归档日志,所以必须处于归档模式,才能进行恢复,答案选择C
wangtong
发表于 2016-10-28 16:45:03
86:
View the Exhibit and examine the user information.
The user has been granted CONNECT and RESOURCE roles and no individual system privileges. The SL_REP user executes this command to create a table:
SQL> CREATE TABLE orders (
oid number(6), odate date,
ccode number(4), oamt number(10,2)
) TABLESPACE purchase_space;
The PURCHASE_SPACE tablespace already exists in the database.
Which statement describes the effect of the command?
A. The command executes successfully and creates the table in the USERS tablespace.
B. The command executes successfully and creates the table in the PURCHASE_SPACE tablespace.
C. The command produces an error because the user does not have the privilege to createthe table.
D. The command produces an error because the user does not have quota in the PURCHASE_SPACE tablespace.
86:
查看下表检查用户信息
用户被授予CONNECT和RESOURCE角色并且没有单独的系统权限。SL_REP用户执行这个命令去创建一个表:
SQL> CREATE TABLE orders (
oid number(6), odate date,
ccode number(4), oamt number(10,2)
) TABLESPACE purchase_space;
哪个语句是正确描述这个命令的影响?
A. 命令执行成功并且创建表在USERS表空间
B. 命令执行成功并且创建表在PURCHASE_SPACE表空间
C. 命令执行报错因为用户没有权限创建表
D. 命令执行报错因为用户在PURCHASE_SPACE表空间没有配额
答案:B
RESOURCE角色包含Create Table系统权限,所以可以创建表,创建语句中指定了表空间,故B正确
参考官方文档:
http://docs.oracle.com/cd/E11882_01/network.112/e36292/authorization.htm#DBSEG99936
wangtong
发表于 2016-10-28 16:47:49
87:
A constraint in a table is defined with the INITIALLY IMMEDIATE clause. You executed the ALTER TABLE command with the ENABLE VALIDATE option to enable the constraint that was disabled. What are the two effects of this command? (Choose two.)
A. It fails if any existing row violates the constraint.
B. It does not validate the existing data in the table.
C. It enables the constraint to be enforced at the end of each transaction.
D. It prevents insert, update, and delete operations on the table while the constraint is in the process of being enabled.
87:
一个表上的约束使用INITIALLY IMMEDIATE子句定义。你执行ALTER TABLE命令使用ENABLE VALIDATE选项去启用被禁用的约束。这个命令的两个影响是什么?(选择两个)
A. 将会失败如果任何现有行违反约束
B. 它不会验证表中已经存在的数据
C. 它会启用约束强制执行在每个事务的末期
D. 阻止在表上的插入、更新和删除操作当约束被启用的时候
答案:AD
INITIALLY IMMEDIATE表示初始化立即执行,在每条语句执行结束时检验约束
ENABLE VALIDATE表示原有的和新加的数据都必须遵循约束条件
A正确,B错误,ENABLE VALIDATE会验证已经存在的数据是否违反约束
C错,INITIALLY DEFERRED才是事务提交之后检查约束
D正确,ENABLE VALIDATE会阻止插入、更新和删除操作来保证数据一致性
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e41084/clauses002.htm
wangtong
发表于 2016-10-28 16:48:52
88:
The session of user SCOTT receives the following error after executing an UPDATE command on the EMP table:
ERROR at line 1:
ORA-00060: deadlock detected while waiting for resource
On investigation, you find that a session opened by user JIM has a transaction that caused the deadlock.
Which two statements are true regarding the session of SCOTT in this scenario? (Choose two.)
A. The session is terminated after receiving the error and JIM can continue with his transaction.
B. SCOTT should perform a COMMIT or ROLLBACK to allow JIM to continue with his transaction.
C. The session is rolled back after receiving the error and JIM can continue with his transaction.
D. SCOTT has to reexecute the last command in the transaction after he commits the transaction.
88:
用户SCOTT收到下面错误在EMP表上执行一个UPDATE命令之后:
ERROR at line 1:
ORA-00060: deadlock detected while waiting for resource
经调查,你发现用户JIM打开的会话有一个事务导致死锁
哪两句是正确的关于这个场景下的SCOTT?(选择两个)
A. 会话中止在收到报错之后并且JIM可以继续它的事务
B. SCOTT需要执行一个COMMIT或者ROLLBACK去允许JIM继续它的事务
C. 会话回滚在收到报错之后并且JIM可以继续它的事务
D. SCOTT不得不重新执行事务的最后一个命令在它提交它的事务之后
答案:BD
死锁是锁定冲突的特殊示例。两个或多个会话等待由对方锁定的数据时,就会发生死锁。因为每个会话都在等待另一个会话释放锁定,所以任何一个会话都不能完成事务处理,也不能解决冲突。Oracle 数据库会自动检测死锁并终止语句,同时显示错误消息。更正这种错误的适当做法是执行提交或回退,这样做会在一个会话中释放任何其它锁定,以便其它会话可继续完成其事务处理。scott必须提交或回退,才能更正检测到的死锁误。如果执行提交,则必须重新提交第二次更新才能完成事务处理。如果执行回退,则必须同时重新提交这两个语句才能完成事务处理。
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e40540/consist.htm#CNCPT1336
wangtong
发表于 2016-10-28 16:49:17
89:
Examine the following statement that is used to modify the primary key constraint on the SALES table:
SQL> ALTER TABLE SALES MODIFY CONSTRAINT pk DISABLE VALIDATE;
Which three statements are true regarding the above command? (Choose three.)
A. The constraint remains valid.
B. The index on the constraint is dropped.
C. It allows the loading of data into the table using SQL *Loader.
D. New data conforms to the constraint, but existing data is not checked.
E. It allows the data manipulation on the table using INSERT/UPDATE/DELETE SQL statements.
89:
检查下面用于修改SALES表主键约束的语句:
SQL> ALTER TABLE SALES MODIFY CONSTRAINT pk DISABLE VALIDATE;
哪三句是正确的关于上面的命令?(选择三个)
A. 约束仍然有效
B. 约束上的索引被删除
C. 允许使用SQL*Load加载数据到表中
D. 新的数据符合约束,已经存在的数据不会被检查
E. 允许在表上对数据使用INSERT/UPDATE/DELETE SQL语句
答案:ABC
DISABLE 和ENABLE 是针对新增的数据是否符合约束,NOVALIDATE 和VALIDATE是针对已经存在的数据是否符合约束。
DISABLE NOVALIDATE:不检查新数据和现有数据,因此这些数据可能不符合约束条件。当数据来自验证过的源,而且表是只读表时,通常会使用此状态。因此,不会将新数据输入表中。在已清理了数据的数据仓库环境中使用NOVALIDATE。此时不需要进行验证,因而可以节省很多时间。
DISABLE VALIDATE:如果约束条件处于此状态,则不允许对有约束条件的列进行任何修改。因为如果在验证现有数据后,又允许将未经检查的数据输入表中,就会出现不一致的情况。通常,在必须验证现有数据但不进行修改时,以及不需要索引来提高性能时,可使用此状态。
ENABLE NOVALIDATE:新数据符合约束条件,但现有数据处于未知状态。通常在确信表中只存在纯净数据和符合规则的数据的情况下使用该状态,此时不需要进行验证。但是,不允许将违反规则的新数据输入到系统中。
ENABLE VALIDATE:新数据与现有数据均符合约束条件。这是约束条件的典型状态和默认状态。
A正确,因为DISABLE VALIDATE对现有的数据仍然有约束
B正确,因为DISABLE VALIDATE状态会删除索引
C正确,因为DISABLE VALIDATE对新增加的数据没有约束
D错误,因为DISABLE VALIDATE是对现有的数据有约束,新增的没有
E错误,因为DISABLE VALIDATE不允许对有约束条件的列进行任何修改
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e41084/clauses002.htm#i1002038
wangtong
发表于 2016-10-28 16:49:57
90:
You execute the following command to change the status of the SALES tablespace:
SQL> ALTER TABLESPACE sales OFFLINE;
Which statements describe the effect of the command? (Choose all that apply.)
A. The tablespace would require recovery to go back online.
B. A checkpoint is taken on all data files that are associated with the SALES tablespace.
C. The sessions that subsequently try to access the objects in the SALES tablespace receive an error.
D. The new status of the SALES tablespace is recorded in the control file when the database instance is closed.
90:
你执行下面的命令改变SALES表空间的状态:
SQL> ALTER TABLESPACE sales OFFLINE;
哪些语句描述了命令的影响?(选择所有合适的)
A. 表空间需要恢复才能回到online状态
B. 检查点会记录在SALES表空间关联的所有数据文件
C. 会话随后访问SALES表空间的对象会收到一个错误
D. 当数据库实例关闭,SALES表空间的新状态被记录在控制文件中
答案:BC
表空间offline选项:
Normal(正常):如果表空间中的任何数据文件不存在任何错误状态,可通过正常方式使表空间脱机.表空间脱机时,会对表空间中的所有数据文件设置检查点,可以确保将所有数据写入磁盘.
Temporary(临时):如果表空间中的一个或多个文件存在错误状态,也可以使表空间暂时脱机.尚未脱机的数据文件脱机时,会对这些数据文件设置检查点.如果没有任何文件脱机,但是使用了临时子句,使表空间重新联机时便不需要执行介质恢复.但是,如果因写错误而导致表空间的一个或多个文件脱机,而且设置了表空间临时脱机,那么表空间需要执行恢复后才能重新联机.
Immediate(立即)表空间可以立即脱机,Oracle 数据库不需要对任何数据文件设置检查点.如果指定了"Immediate",则必须先对表空间执行介质恢复 recover tablespace ,才能使表空间联机.如果数据库在 NOARCHIVELOG 模式下运行,则无法立即使表空间脱机.
因为是正常的offline表空间,所以不需恢复,即可online,A错
正常的offline表空间,会对所有数据文件设置检查点,B对
不能访问offline的表空间,C对
表空间offline时会立即记录在控制文件,而不是关闭的时候才记录,D错
wangtong
发表于 2016-10-31 17:51:16
91:
You are working on a database that must be functioning 24 hours a day, 7 days a week. The database is configured in ARCHIVELOG mode.
Which two options do you have for performing user-managed backups? (Choose two.)
A. You can perform consistent backups only.
B. You can perform a complete database backup without shutting down the database instance.
C. You can back up data files only when all data files have the same SCN recorded in the control file.
D. You can back up only those data files whose headers are frozen by using ALTER TABLESPACE BEGIN BACKUP or ALTER DATABASE BEGIN BACKUP commands.
91:
你工作在一个7×24小时工作的数据库。数据库配置为ARCHIVELOG模式。
哪两个种是你可以执行用户管理的备份?(选择两个)
A. 你只可以执行一致性备份
B. 你可以执行一个完整的数据库备份在数据库实例不关闭的情况下
C. 你可以备份数据文件只有在在控制文件中所有数据文件拥有相同的SCN记录时
D. 你可以备份只有那些文件头使用ALTER TABLESPACE BEGIN BACKUP或者ALTER DATABASE BEGIN BACKUP命令冻结的数据文件
答案:BD
归档模式:可以进行一致性备份(冷备)和非一致性备份(热备)。
非归档模式:一致性备份(冷备)
一致性备份(冷备份):在数据库正常关闭情况下做备份,数据库处于一致性状态。
(可以用于归档和非归档),所有SCN号一致。缺点:数据库需要关闭。
非一致性备份(热备份):数据库在open状态下备份(用于归档模式),
使用alter database/tablespace xxx begin backup开始备份,此时会冻结数据文件文件头。
wangtong
发表于 2016-10-31 17:51:36
92:
You have set Tablespace Full Metrics Threshold values for the USERS tablespace as follows:
Warning (%): 90
Critical (%): 95
Which background process is responsible for issuing alerts when the threshold is crossed?
A. System monitor (SMON)
B. Process monitor (PMON)
C. Memory manager process (MMAN)
D. Manageability Monitor process (MMON)
92:
你设置USERS表空间的Tablespace Full Metrics Threshold值为下面:
Warning (%): 90
Critical (%): 95
哪个后台进程负责阈值超出时发出警报?
A. System monitor (SMON)
B. Process monitor (PMON)
C. Memory manager process (MMAN)
D. Manageability Monitor process (MMON)
答案:D
可管理性监视器进程(MMON),可执行各种与可管理性相关的后台任务,例如:
• 每当给定的度量超过其阈值时发出预警
• 通过衍生附加进程(MMON 从属进程)获取快照
• 捕获近期已做修改的SQL 对象的统计值
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e40540/process.htm#BABJAIBD
wangtong
发表于 2016-10-31 17:51:54
93:
User SCOTT executes the following command on the EMP table but has not issued COMMIT, ROLLBACK, or any data definition language (DDL) command:
SQL> SELECT ename FROM emp
2 WHERE job='CLERK' FOR UPDATE OF empno;
SCOTT has opened another session to work with the database instance. Which three operations would wait when issued in SCOTT's second session? (Choose three.)
A. LOCK TABLE emp IN SHARE MODE;
B. LOCK TABLE emp IN EXCLUSIVE MODE;
C. UPDATE emp SET sal=sal*1.2 WHERE job='MANAGER'
D. INSERT INTO emp(empno,ename) VALUES (1289,'Harry');
E. SELECT ename FROM emp WHERE job='CLERK' FOR UPDATE OF empno;
93:
用户SCOTT执行下面命令在EMP表上但是没有COMMIT,ROLLBACK或者任何DDL命令:
SQL> SELECT ename FROM emp
2 WHERE job='CLERK' FOR UPDATE OF empno;
SCOTT打开了另一个会话与数据库实例。哪三种操作会等待当在SCOTT的第二个会话执行的时候?(选择三个)
A. LOCK TABLE emp IN SHARE MODE;
B. LOCK TABLE emp IN EXCLUSIVE MODE;
C. UPDATE emp SET sal=sal*1.2 WHERE job='MANAGER'
D. INSERT INTO emp(empno,ename) VALUES (1289,'Harry');
E. SELECT ename FROM emp WHERE job='CLERK' FOR UPDATE OF empno;
答案:ABE
这个select ... for update 是在TX加上了S锁,在TM上增加了SX锁,
因此不能在TX上增加X锁,不能在TM上增加S、SSX、X锁
A:正确,这个相当于TMS锁
B:正确,这个是TM的X锁
C:这里只是TM的SX锁
D:和C一样
E:正确,这里是SX锁,锁的是不同的记录
wangtong
发表于 2016-10-31 17:52:42
94:
Which three statements are true about logical structures of the Oracle database? (Choose three.)
A. Each segment contains one or more extents.
B. Multiple tablespaces can share a single data file.
C. A data block is the smallest unit of input/output (I/O) in data files.
D. It is possible to have tablespaces of different block sizes in a database.
E. Each data block in the database always corresponds to one operating system block.
94:
哪三个语句是正确的关于Oracle数据库的逻辑结构?(选择三个)
A. 每个段包含一个或多个区
B. 多个表空间可以共用一个数据文件
C. 数据块是数据文件最小的I/O单元
D. 一个数据库中可能有不同的块大小的表空间
E. 数据库中的每个数据块总是和操作系统块保持一致
答案:ACD
A段是由一个或多个去组成的,故正确
B一个数据文件只能属于一个表空间,一个表空间可以有多个数据文件,错误
C Oracle Data Block是最小的I/O单位,正确
D 可以指定非标准快大小的表空间
E 数据库里的块大小可以和操作系统一致,也可以是其的整倍数,错误
wangtong
发表于 2016-10-31 17:53:17
95:
You are managing an Oracle Database 11g database. You configured the database to run in ARCHIVELOG mode.
Which two statements are true in this scenario? (Choose two.)
A. You must shut down the database instance to perform the backups.
B. You must configure the Flash Recovery Area (FRA) for the database.
C. You can perform complete database backups without closing the database.
D. All the previous closed database backups including control files become invalid after you configure the database to ARCHIVELOG mode.
95:
你正在管理一个Oracle Database 11g数据库。你配置数据库为ARCHIVELOG模式。哪两句是正确的在这个场景?(选择两个)
A. 你必须关闭数据库才能执行备份
B. 你必须为数据库配置Flash Recovery Area
C. 你可以执行完整的数据库备份没有关闭数据库的情况下
D. 在你设置数据库为ARCHIVELOG模式之后,所有之前的相关数据库备份包括控制文件变得无效
答案:CD
A.在归档模式下,可以进行数据库非一致性备份,即热备份。不需要关闭数据库来备份。
B.在归档模式下,不用必须指定快速恢复区,归档日志可以重新自己指定本地位置或远程位置来归档。
C.在归档模式下,可以进行完成的数据库备份,而不需要数据库关闭。
D.在非归档转为归档模式后,或者重新配置成归档模式,之前所有的备份,包括控制文件,都已经变为无效的,因为日志信息的序列号是重头开始的。
wangtong
发表于 2016-10-31 17:53:43
View the Exhibit to examine the output of the DBA_OUTSTANDING_ALERTS view. After 30 minutes, you executed the following command:
SQL> SELECT reason,metric_value FROM dba_outstanding_alerts;
REASON METRIC_VALUE
----------------------------------------------- ----------------
Tablespace is full 28.125
What could be the reason for the elimination of the other rows in the output?
A. An Automatic Workload Repository snapshot has been taken recently.
B. The non-threshold-based alerts are transferred to DBA_ALERT_HISTORY.
C. The threshold alerts conditions are cleared and the alerts are transferred to BA_ALERT_HISTORY.
D. The threshold alerts related to database metrics are permanently stored in DBA_ALERT_HISTORY but not the threshold alerts related to instance metrics.
96:
查看下图检查DBA_OUTSTANDING_ALERTS视图的输出。30分钟之后,你执行下面的命令:
SQL> SELECT reason,metric_value FROM dba_outstanding_alerts;
REASON METRIC_VALUE
----------------------------------------------- ----------------
Tablespace is full 28.125
可能是什么原因消除输出中的行?
A. 采取最近一个自动负载知识库快照
B. 非基于阈值的alert被转移到DBA_ALERT_HISTORY
C. 基于阈值的alert条件被清除并且alert转移到DBA_ALERT_HISTORY
D. 基于阈值的alert数据库相关的指标被永久的存储在DBA_ALERT_HISTORY而不是基于阈值的alert实例相关的指标
答案:C
服务器生成预警分为两种类型:阈值预警和非阈值预警。
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度量与数据库相关外,其它度量都与实例相关。阈值预警又称为“有状态预警”,清空预警条件后,会自动清空这些预警。有状态预警显示在
DBA_OUTSTANDING_ALERTS中,清空后会转到DBA_ALERT_HISTORY。
服务器生成的其它预警对应于特定的数据库事件,如ORA-*错误、“快照太旧”错误、“恢复区空闲空间过少”和“可恢复会话被挂起”等。这些都不是基于阈值的预警,又称
为“无状态预警”。无状态预警会直接转到历史记录表。只在Database 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。
wangtong
发表于 2016-10-31 17:55:28
97:
You have two database servers SEMP and SACCT. The database in the SEMP server maintains the employee information and the database in the SACCT server maintains the accounts payable information. The employees submit the expense reports to the accounts payable department. A user of the accounts payable database wants to extract the employee information from the database in the SEMP server for cross verification.
Which schema object enables the user to access the information from the remote database?
A. Cluster
B. Database link
C. Mapping table
D. Materialized view
97:
你有两个数据库服务器SEMP和SACCT。SEMP服务器上的数据库维护员工的信息,SACCT服务器上的数据库维护账户应付款信息。员工提交账户应付款部门的费用报告。一个账户应付款数据库的用户想提取员工信息从SEMP服务器上数据库进行交叉验证
哪个方案对象启用可以使用户访问远程数据库的信息?
A. Cluster
B. Database link
C. Mapping table
D. Materialized view
答案:B
使用DB Link可以实现数据库的远程连接,关于DB Link的介绍,
参考官方文档:
http://docs.oracle.com/cd/E11882_01/server.112/e25494/ds_concepts.htm#ADMIN12084
wangtong
发表于 2016-10-31 17:57:26
98:
In a new installation of Oracle Database 11g, you perform these activities:
1. Organize software and data on different subdirectories to avoid poor performance.
2. Use consistent naming conventions for database files.
3. Separate administrative information pertaining to the database in different directories.
Which option corresponds to the type of activities you performed?
A. Oracle Managed Files
B. Oracle Grid Architecture
C. Optimal Flexible Architecture
D. Oracle database architecture
E. Automatic Storage Management
98:
在一个新安装的Oracle Database 11g数据库,你执行下面活动:
1. 组织软件和数据在不同的子目录,避免性能不佳
2. 使用统一的命名惯例为数据库文件
3. 分开管理权限信息在不同目录
哪个选项对应的你指定的活动?
A. Oracle Managed Files
B. Oracle Grid Architecture
C. Optimal Flexible Architecture
D. Oracle database architecture
E. Automatic Storage Management
答案:C
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,因为目录规范,命名规范,这样软件不会冲突,方便管理,文件也方便查找。通过遵循OFA的指导,使得整个系统可以更加灵活
参考官方文档:
http://docs.oracle.com/cd/E11882_01/install.112/e47689/appendix_ofa.htm#LADBI1377
wangtong
发表于 2016-10-31 17:58:45
99:
You configured the Flash Recovery Area (FRA) for your database. The database instance is running in ARCHIVELOG mode. The default location for the archived redo log files is the Flash Recovery Area.
Which two files are removed automatically if the space is required in the FRA as per the retention policy? (Choose two.)
A. Flashback log files
B. Backups that have become obsolete
C. User managed backups of the data files and control files
D. Archived redo log files that have multiple copies in a different archive location and not backed up
99:
你为你的数据库配置Flash Recovery Area(FRA)。数据库实例处于ARCHIVELOG模式。默认的归档日志路径是Flash Recovery Area
哪两个文件自动删除如果FRA按照保留策略需要空间?
A. 闪回日志文件
B. Obsolete的备份
C. 用户管理的数据文件和控制文件备份
D. 没有备份的归档日志文件有多路复用的备份在不同的归档路径
答案:AB
快速恢复区的空间管理由备份保留策略控制。保留策略确定文件何时过时,即何时这些文
件对达到数据恢复目标已不再有用。Oracle DB 通过删除不再需要的文件自动管理该存储。
参考官方文档:
http://docs.oracle.com/cd/E11882_01/backup.112/e10642/rcmcncpt.htm#BRADV89505