从Oracle 9i开始,Oracle缺省使用spfile启动数据库,spfile必须由pfile创建,新建的spfile将在下一次启动数据库时生效。pfile为初
从Oracle 9i开始,Oracle缺省使用spfile启动数据库,spfile必须由pfile创建,新建的spfile将在下一次启动数据库时生效。
pfile为初始化参数文件(Initialization Parameters Files),Oracle 9i之前,Oracle通过pfile储存初始化参数,该文件为文本文件,可手工修改。
spfile为服务器参数文件(Server Parameters Files),Oracle 9i之后引入,为数据文件,不可手工修改。
在Oracle9i之前,修改初始化参数需要通过手工修改pfile文件来完成,实例启动时才会从pfile中读取初始化参数,因此重启实例才会使修改参数生效。引入spfile后,可以直接通过命令来修改参数(alter system),对动态参数修改可以直接生效,并可同时设置该参数的scope,静态参数的scope必须是spfile,在重启后才会生效。
文件的目录分别为:
pfile:
/home/oracle/oracle/admin/TESTDB/pfile/init.ora.6112012111012
spfile:
/home/oracle/oracle/product/10.2.0/db_1/dbs/spfileTESTDB.ora
1.如果spfile被损坏了,,不存在,那么重启数据库就会报找不到spfile的错误
这时需要通过——!):
并且重启数据库
缺省条件下,spfile会被创建到系统缺省目录
备注:
1,通过spfile文件创建pfile文件
];
2,通过pfile文件创建spfile文件
];
3,通过spfile文件修改动态参数
parameter=Value scope=memory|spfile|both
memory:只改变当前实例运行,重启数据库后失效
spfile:只改变spfile设置,不改变当前实例设置,重启数据库后生效
both:同时改变spfile和实例设置,当前更改立即生效,重启后依然有效
4,Startup nomount的时候需要读去spfile或pfile两者共存,spfile优先

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