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Oracle 参数文件介绍

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Jun 07, 2016 pm 04:44 PM

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Oracle数据库启动以后，通过select * from v$parameter这个语句可以查看到Oracle数据库使用的所有参数。对于Oracle的参数文件，分

Oracle数据库启动以后，通过select * from v$parameter这个语句可以查看到Oracle数据库使用的所有参数。

对于Oracle的参数文件，分为spfile 二进制文件和pfile 文本文件，现在的数据库一般都是使用spfile二进制文件作为启动Oracle的参数文件。对于spfile和pfile之间的区别：

1 spfile是二进制文件（可以通过 string spfileorcl.ora进行二进制的文件查看），不可以使用文本编辑器修改，只能在sqlplus中使用命令动态修改参数。对于pfile是文本文件，可以直接使用文本编辑器进行修改，，重启数据库后生效

2 spfile必须存储在服务端，一般是在$Oracle_HOME/dbs目录下面，对于pfile则是可以存储在客户端，可以通过客户端的pfile启动数据库

3 spfile 和pfile之间可以动态转化在sql命令下（不管是否已近启动数据库实例）

通过pfile创建spfile create pfile=’/u01/app/Oracle/dbs/spfileorcl.ora’ from pfile=’/u01/app/Oracle/dbs/initorcl.ora’(或者使用 create spfile from pfile)

4 如果启动数据库start 不指定参数文件（如果sid是orcl），则会在$Oracle_HOME/dbs 目录下依次寻找参数文件 spfileorcl.ora>initorcl.ora

5 我们可以指定参数文件来启动数据库(这里只能通过pfile文件，不能是spfile文件)

startup pfile='/u01/app/Oracle/dbs/init.ora'（使用pfile文件）

6 对于参数文件中没有指定的参数，均是采取相关参数的默认值

Oracle 表的创建及相关参数

从参数取值看Oracle OMF特性

Oracle 10g的隐含参数_complex_view_merging引发的性能问题

Oracle 11g RAC 中几个重要参数的解释

Oracle开启归档模式及其相关参数

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