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1.说一下RAC和单节点数据库的区别有哪些？你认为RAC最有用的功能是说什么？区别（1）RAC有2个以上的实例，单节点只有1个实例（2）RAC具有实例级别的高可用（3）实例与实例之间通过内联网络交换数据，单节点不可（4）...

在Oracle 10g中的等待事件有872个，11g中等待事件1116个。 我们可以通过v$event_name 视图来查看等待事件的相关信息一． 等待事件的相关知识1.1 等待事件主要可以分为两类，即空闲(IDLE)等待事件和非空闲(NON-IDLE)等待事件。1). 空闲等待事件指ORACLE正等待某种工作，在诊断和优化数据库的时候，不用过多注意...

656 The BACKUP_TAPE_IO_SLAVES parameter is set to FALSE for the database instance. Which statement istrue while performing a tape backup in an RMAN session?A. The tape I/O performed is asynchronousB. The tape buffer is allocated from the System GlobalArea (SGA)C. The tape buffer is...

686. You execute the following FLASHBACK TABLE command: Which two statements are correct?(Choose two.)A.The EMP table that was dropped by  mistake earlier is restored.B.The FLASHBACK TABLE statement is  executed as a single transaction.C.The FLASHBACK TABLE state...

698. In your production database, you:-Are using Recovery Manager (RMAN) with a recovery catalog to perform the backup operation at regular intervals-Set the control file autobackup to “on”-Are maintaining image copi es of the database filesYou have lost the server parameter...

分类： Linux原文地址：Redo丢失的4种情况及处理方法 作者：尛样儿一.说明：1.以下所说的当前日志指日志状态为CURRENT,ACTIVE,非当前日志指日志状态为INACTIVE2.不用考虑归档和非归档模式，2种模式下的Redo丢失情况一样。二.丢失Redo的4种情况：第一种情况：非当前日志，...

635.While Monitoring the space usage in your database that is in ARCHIVELOG mode you observed thatthe flash recovery area does not have enough free space to accommodate any more files and you do nothave necessary permissions to add more space to it.Identify the two events that can occur in the ...

586.Consider the following command:Backup database plus archivelog delete input;How many backup sets would be created by this command if the following were true:Control-file a NN uto backups were enabled.NN The size of backup sets was not restricted.NN One channel was allocated.A. 1B. 2C. 3...

ASMM (Auto Shared Memory Manangement) Oracle只需要设置一个SGA总大小，10g会根据系统负载变化调节各内存组件大小。开启ASMM, 需要设置sga_target 及 statistics_level=typical/all 即可(basic表示关闭asmm)。&n...

tuning advisor 是对输入的sql set的执行计划进行优化accsee advisor 是对sql set当前如果引入索引、分区的话，性能有多大的提升，给出建议。

394.Which of the following statements is true regarding the initialization parameter DIAGNOSTIC_DEST?A. The default value is the value of the environment variable $ORACLE_HOME;       if $ORACLE_HOME isn't set,then the default is set to $ORACLE_BASE.B. The defa...

db_file_name_convert和log_file_name_convert是用来转化数据，在线和standby日志文件的位置。主要用在物理standby数据库和rman数据库复制和TSPITR的操作。这里以standby database为例子，说明这俩个参数的应用。...

343.What is the impact of the following backup if it exceeds the duration allowance? (Choose all thatapply.)Backup as compressed backupset duration 2:00 partial minimize load database ;A. The entire backup will fail. It will not be usable for recovery.B. The entire backup will fail, bu...

从Oracle 10g以后数据库升级前我们都需要将实例关闭，并以startup upgrade的升级模式启动数据库。那么startup upgrade到底对instance做了什么事？在这样的模式下升级可以绕过那些错误呢？就常规判断可以猜测startup upgrade升级模式至少会限制以下几点:    关闭自动作业队列    关闭回...

ASM_POWER_LIMIT 参数　这个参数 ASM_POWER_LIMIT 参数控制 ASM 后台进程 ARBx 的数量。ARBx 进程用来进行 ASM 磁盘数据重新分布打散。ASM_POWER_LIMIT 取值 从 0 到 11(据说从 10gR2 开始可以设置为 0，设置为0是为...