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Jun 07, 2016 pm 03:17 PM

oracleparameterdocumentCommunityEnter

欢迎进入Oracle社区论坛，与200万技术人员互动交流 >>进入参数文件的相关问题。一、查看数据库中参数值的方法 1、查看initsid.ora文件。不提供所有参数；参数可能已经更改，文件中的参数值不是最新值(新值可能在spfile中，而initsid.ora文件中没有更新)。

欢迎进入Oracle社区论坛，与200万技术人员互动交流 >>进入

参数文件的相关问题。

一、查看数据库中参数值的方法

1、查看initsid.ora文件。

　　不提供所有参数；参数可能已经更改，文件中的参数值不是最新值(新值可能在spfile中，而initsid.ora文件中没有更新)。

2、查询视图V$PARAMETER。

　　可利用它来确定参数的默认值是否修改过，以及是否可以用alter system和alter session命令修改。

　　应该特别注意ISMODIFIED、ISDEFAULT、ISADJUSTED、ISSYS＿MODIFIABLE、ISSES＿MODIFIABLE列中的值。

3、使用SQL*Plus的show parameter。

二、设置参数的方法

1、修改initsid.ora文件。

　　可以修改所有的参数，必须关闭并重启实例才能生效。

2、使用alter system、alter system deferred和alter session命令。

　　不能修改所有参数，修改后可立即生效，并可保存到spfile或init文件中。

三、缺省情况下，Oracle9i启动时读取参数文件的顺序

　　重新启动数据库，使用startup命令，Oralce将会按照以下顺序在缺省目录中搜索参数文件：

　a. spfile$.ora

　　　　　缺省目录 UNIX: $/dbs/

　　　　　NT: $/database

　b. spfile.ora

　　　　　缺省目录 UNIX: $/dbs/

　　　　　NT: $/database

　c. init$.ora

　　　　　缺省目录 UNIX: $/dbs/

　　　　　NT: $/database

　　　　　or $/admin/db_name/pfile/

oracle参数文件

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