归档日志路径三个参数DB_RECOVERY_FILE_DEST和LOG_ARCHIVE_DEST和LOG_ARCHIVE_DEST_n
LOG_ARCHIVE_DEST:指定归档文件存放的路径,该路径只能是本地磁盘,默认为’’。LOG_ARCHIVE_DEST_n:默认值为’’。Oracle最多支持把日志文件归档到10个地方,n从1到10。归档地址可以为本地磁盘,或者...
Oracle中control_file_record_keep_time和MAXLOGHISTORY参数
Oracle基于RMAN的备份方式可以分为catalog和nocatalog两种方式进行备份管理。其中,catalog方式需要一个catalog目录数据库,这个数据库一般运行在另外一台服务器上,RMAN把对数据库的备份恢复记录保留在ca...
lsnrctl中,SET PASSWORD和CHANGE_PASSWORD命令
CHANGE_PASSWORD Use the CHANGE_PASSWORD command to establish anencrypted password or change an encrypted password set with the PASSWORDS_listener_name parameter in the listener.ora file....
Oracle Scheduler概述
一、Overview of the SchedulerOrganizations havetoo many tasks, and manually dealing with each one can be daunting. To help yousimplify these management tasks, as well as offering a rich set off...
EMPHASIS和RATIO policy比较
1、 EMPHASISEMPHASIS CPU分配方法确定在resource plan中对不同consumer groups中的会话的重视程度。CPU占用率的分配级别为从1 到8,级别1的优先级最高。百分比指定如何将CPU资源分配给每一级中的各个co...
Oracle pending area
Ifyou do not use Enterprise Manager to create the resource plan or resourceconsumer groups,you must first create a pending area.Thefirst thing you must do to create or modify plan schem...
Oracle simple resource plan
You can quickly create a simple resource plan that willbe adequate for many situations using the CREATE_SIMPLE_PLAN procedure. This procedure enables you to create consumergroups and alloc...
Oracle SYSTEM_PLAN
SYSTEM_PLAN资源计划是提供的默认计划之一。它包含适用于下列使用者组的指令:l SYS_GROUP:SYS和SYSTEM用户的初始使用者组。l OTHER_GROUPS:用于所有属于活动资源计划之外...
Oracle Automatic PGA Memory Management
理想情况下,工作区的大小足够大到能容纳其相关SQL运算符分配的输入数据和辅助内存结构,这一大小被称为工作区的最佳大小。工作区大小小于最佳大小时,响应时间就会增加,因为要对部分输入数据执行额外的传输操作...
Oracle DB_nK_SIZE_CACHE参数
TheOracle database supports multiple block sizes in the same database.The standardblock size is used for the SYSTEM tablespace.You specify the standard blocksize by setting the initializa...
Oracle ASM添加磁盘组POWER OPTION
Use thisclause to manually rebalance the disk group. Automatic Storage Managementredistributes datafiles evenly across all drives. This clause is rarelynecessary, because Automatic Storag...
ASM Disk Group Template
一、template定义、作用 Templates areused to set redundancy (mirroring) and striping attributes of files created inan ASM disk group. When a file is created, redundancy and stripin...
Oracle Index-organized table (IOT)概述
一、几种表类型 Type Description Ordinary(heap-organized) table Data is stored as an unordered collection (heap). Partitioned table...
oracle shrink
一、shrink segment两个好处 You use online segment shrink to reclaim fragmented free spacebelow the high water mark in an Oracle Database segment. The benefits ofsegment shrink are these:...
参数FAST_START_MTTR_TARGET的理解
一、FAST_START_MTTR_TARGET参数的作用和实现方法 参数FAST_START_MTTR_TARGET参数是一个加快实例恢复的参数,我们可以根据服务界别来定义一个合理的、可接受的值。该值得单位为秒。比如设定为60...
oracle db、dba和rdba
一、 DB(Data Block) 1、dumping data blocks SYS@ tsid > select 2 dbms_rowid.rowid_relative_fno(rowid) REL_FNO, 3 dbms_r...
Oracle ROWID概述
一、ROWID概念Aglobally unique address for a row in a database.ROWID 是一个类似于rownum的伪列,用于定位数据库中一条记录的一个相对唯一地址值。通常情况下,该值在该行数据插入到数据库表...
使用dbms_rowid包获得ROWID的详细信息
定义自定义函数get_rowid获得rowid的详细信息。 SYS@ tsid > create or replace functionget_rowid 2 (l_rowid in varchar2) 3 return varchar2 4 i...
使用oracle utl_raw作为dump的逆函数
对于dump出来的内容,通常不能直观的了解到想要的信息,可以通过utl_raw来实现。1、 转换数字(1)、整数SYS@ tsid> select dump(156983,16) from dual; DUMP(156983,16)--------...
RMSN 块介质恢复(BMR)--BLOCKRECOVER
RMAN的BLOCKRECOVER命令可以对corrupted块进行BlockMedia Recovery(BMR)块介质恢复。 BMR的优点:1、 BMR将介质恢复的最小可恢复单位从数据文件缩小到块。如果已知数据库中只有少量...