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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

This parameter sets the password for user SYS. If you issue the ALTER USERstatement to change the password for SYS after connecting to the database, both thepassword stored in the data dictionary and the password stored in the password fileare updated. This parameter is mandatory.Note: You cannot change the password for SYS ifREMOTE_LOGIN_PASSWORDFILE is set to SHARED. An errormessage is issued if you attempt to do so.orapwd参数之 : PASSWORD1. 指定sys用户的密码 , 该参数是必须的.2. 如果使

This parameter sets the name of the password file being created. You must specify thefull path name for the file. The contents of this file are encrypted, and the file cannot beread directly. This parameter is mandatory.The types of filenames allowed for the password file are operating system specific.Some operating systems require the password file to adhere to a specific format and belocated in a specific directory. Other operating systems allow the use of environmentvariables to specify the n

When you invoke this password file creation utility without supplying anyparameters, you receive a message indicating the proper use of the command asshown in the following sample output:> orapwdUsage: orapwd file=<fname> password=<password> entries=<users> force=<y/n>wherefile - name of password file (mand),password - password for SYS (mand),entries - maximum number of distinct DBAs and OPERs (opt),force - whether to overwrite existing file (opt)There are no spaces ar

Administrative users can be connected and authenticated to a local or remote databaseby using the SQL*Plus CONNECT command. They must connect using their usernameand password and the AS SYSDBA or AS SYSOPER clause. For example, user oe hasbeen granted the SYSDBA privilege, so oe can connect as follows:CONNECT oe/oe AS SYSDBAHowever, user oe has not been granted the SYSOPER privilege, so the followingcommand will fail:CONNECT oe/oe AS SYSOPERNote: Operating system authentication takes precedence

This section describes how to authenticate an administrative user using password fileauthentication.Preparing to Use Password File Authentication To enable authentication of an administrative user using password file authentication you must do the following: 1. If not already created, create the password file using the ORAPWD utility: ORAPWD FILE=filename PASSWORD=password ENTRIES=max_users 2. Set the REMOTE_LOGIN_PASSWORDFILE initialization parameter to EXCLUSIVE. (This

OSDBA and OSOPERTwo special operating system groups control database administrator connectionswhen using operating system authentication. These groups are generically referred toas OSDBA and OSOPER. The groups are created and assigned specific names as partof the database installation process. The specific names vary depending upon youroperating system and are listed in the following table:The default names assumed by the Oracle Universal Installer can be overridden. Howyou create the OSDBA and