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Oracle recommends that you create a server parameter file. The server parameter fileenables you to change initialization parameters with database commands and persistthe changes across a shutdown and startup. You create the server parameter file fromyour edited text initialization file. The following script creates a server parameter file from the text initializationparameter file and writes it to the default location. The script can be executed before orafter instance startup, but after you con

You must be authenticated and granted appropriate system privileges in order tocreate a database. You can use the password file or operating system authenticationmethod.第二步 : 建立数据库管理员的认证方式[@more@]

An instance is made up of the system global area (SGA) and the background processesof an Oracle Database. Decide on a unique Oracle system identifier (SID) for yourinstance and set the ORACLE_SID environment variable accordingly. This identifier isused to distinguish this instance from other Oracle Database instances that you maycreate later and run concurrently on your system.The following example for UNIX operating systems sets the SID for the instance thatyou will connect to in Step 4: Connec

When an Oracle instance starts, it reads an initialization parameter file. This file canbe a read-only text file, which must be modified with a text editor, or a read/write binaryfile, which can be modified dynamically by the database (for tuning) or with SQLcommands that you submit. The binary file, which is preferred, is called a serverparameter file. In this step, you create a text initialization parameter file. In a laterstep, you can optionally create a server parameter file from the text f

This section presents the steps involved when you create a database manually. Thesesteps should be followed in the order presented. The prerequisites described in thepreceding section must already have been completed. That is, you have established theenvironment for creating your Oracle Database, including most operating systemdependent environmental variables, as part of the Oracle software installation process.Step 1: Decide on Your Instance Identifier (SID)Step 2: Establish the Database Admin

Oracle export and import utilities enable you to move existing data in Oracle formatbetween one Oracle Database and another. For example, export files can archivedatabase data or move data among different databases that run on the same ordifferent operating systems.数据工具 : Export/Import可在不同的操作系统之间以Oracle的格式 , 将已有的数据进行导入导出[@more@]

SQL*Loader is used both by database administrators and by other users of OracleDatabase. It loads data from standard operating system files (such as, files in text or Cdata format) into database tables.数据工具 : SQL*Loader将标准的操作系统文件导入至数据库表中[@more@]

Oracle Database provides advisors to help you optimize a number of subsystems inthe database. An advisory framework ensures consistency in the way in whichadvisors are invoked and results are reported. The advisors are use primarily by thedatabase to optimize its own performance. However, they can also be invoked byadministrators to get more insight into the functioning of a particular subcomponent.自动管理特性 : 咨询专家优化数据库的不同子系统[@more@]

Some problems cannot be resolved automatically and require the databaseadministrator's attention. For these problems, such as space shortage, Oracle Databaseprovides server-generated alerts to notify you when then problem arises. The alertsalso provide recommendations on how to resolve the problem.自动管理特性 : 服务生成的警告日志对于某些需要DBA手工处理的任务 , 如磁盘空间问题 , Oracle将生成警告日志提醒注意该问题,并且给出解决该问题的建议方案[@more@]

Oracle Database uses the information stored in AWR to identify the need to performroutine maintenance tasks, such as optimizer statistics refresh and rebuilding indexes.Then the database uses the Scheduler to run such tasks in a predefined maintenancewindow.自动管理特性 : 自动维护任务利用AWR中的信息来执行例行任务 , 如调整统计刷新,重建索引[@more@]

Automatic Workload Repository (AWR) is a built-in repository in every OracleDatabase. At regular intervals, the database makes a snapshot of all its vital statisticsand workload information and stores them in AWR. By default, the snapshots aremade every 60 minutes, but you can change this frequency. The snapshots are stored inthe AWR for a period of time (seven days by default) after which they areautomatically purged.自动管理特性 : 自动负载库每60分中 , 数据库对重要的统计数据以负载信息进行快照 ,

Oracle Database has a self-management infrastructure that allows the database tolearn about itself and use this information to adapt to workload variations and toautomatically remedy any potential problem. This section discusses the automaticmanageability features of Oracle Database.自动管理特性利用自动管理框架获得的信息来实例各种信息 , 并用来负载均衡 ,自动修缮各种潜在的问题[@more@]

Oracle Database is a sophisticated self-managing database that automaticallymonitors, adapts, and repairs itself. It automates routine DBA tasks and reduces thecomplexity of space, memory, and resource administration. Several advisors areprovided to help you analyze specific objects. The advisors report on a variety ofaspects of the object and describe recommended actions. Oracle Database proactivelysends alerts when a problem is anticipated or when any of the user-selected metrics.In addition t

Use the V$PWFILE_USERS view to see the users who have been granted SYSDBA orSYSOPER system privileges for a database. The columns displayed by this view are asfollows:USERNAME : This column contains the name of the user that is recognized by thepassword file.SYSDBA : If the value of this column is TRUE, then the user can log on withSYSDBA system privileges.SYSOPER : If the value of this column is TRUE, then the user can log on withSYSOPER system privileges.查看密码文件对象通过视图 V$PWFILE_USERS

If your server is using an EXCLUSIVE password file, use the GRANT statement to grantthe SYSDBA or SYSOPER system privilege to a user, as shown in the followingexample:GRANT SYSDBA TO oe;Use the REVOKE statement to revoke the SYSDBA or SYSOPER system privilege from auser, as shown in the following example:REVOKE SYSDBA FROM oe;Because SYSDBA and SYSOPER are the most powerful database privileges, the WITHADMIN OPTION is not used in the GRANT statement. That is, the grantee cannot in turngrant the

Use the following procedure to create a password and add new users to it:1. Follow the instructions for creating a password file as explained in "UsingORAPWD"2. Set the REMOTE_LOGIN_PASSWORDFILE initialization parameter to EXCLUSIVE.(This is the default.)3. Connect with SYSDBA privileges as shown in the following example:CONNECT SYS/password AS SYSDBA4. Start up the instance and create the database if necessary, or mount and open anexisting database.5. Create users as necessary. Grant

When you grant SYSDBA or SYSOPER privileges to a user, that user's name andprivilege information are added to the password file. If the server does not have anEXCLUSIVE password file (that is, if the initialization parameterREMOTE_LOGIN_PASSWORDFILE is NONE or SHARED, or the password file is missing),Oracle Database issues an error if you attempt to grant these privileges.A user's name remains in the password file only as long as that user has at least one ofthese two privileges. If you revoke b

In addition to creating the password file, you must also set the initialization parameterREMOTE_LOGIN_PASSWORDFILE to the appropriate value. The values recognized are:■ NONE: Setting this parameter to NONE causes Oracle Database to behave as if thepassword file does not exist. That is, no privileged connections are allowed overnonsecure connections.■ EXCLUSIVE: (The default) An EXCLUSIVE password file can be used with onlyone instance of one database. Only an EXCLUSIVE file can be modified. Us

This parameter, if set to Y, enables you to overwrite an existing password file. An erroris returned if a password file of the same name already exists and this parameter isomitted or set to N.orapwd参数之 : FORCE该参数设置为Y , 将覆盖已经存在的密码文件当该参数设置为N , 如果创建的密码文件与现有文件名称相同将返回一个错误[@more@]

This parameter specifies the number of entries that you require the password file toaccept. This number corresponds to the number of distinct users allowed to connect tothe database as SYSDBA or SYSOPER. The actual number of allowable entries can behigher than the number of users, because the ORAPWD utility continues to assignpassword entries until an operating system block is filled. For example, if youroperating system block size is 512 bytes, it holds four password entries. The number ofpassw