Oralce的STARTUP/SHUTDOWN参数
5、startup restrict约束方式启动这种方式能够启动数据库,但只允许具有一定特权的用户访问非特权用户访问时,会出现以下提示:E
1)STARTUP
STARTUP OPEN:STARTUP缺省的参数就是OPEN,打开数据库,允许数据库的访问。当前实例的控制文件中所描述的所有文件都已经打开。
STARTUP MOUNT:MOUNT数据库,仅仅给DBA进行管理操作,不允许数据库的用户访问。仅仅只是当前实例的控制文件被打开,数据文件未打开。
STARTUP NOMOUNT:仅仅通过初始化文件,分配出SGA区,启动数据库后台进程,没有打开控制文件和数据文件。不能任何访问数据库。
STARTUP PFILE= filename:以filename为初始化文件启动数据库,不是采用缺省初始化文件。
STARTUP FORCE:中止当前数据库的运行,并开始重新正常的启动数据库。
STARTUP RESTRICT:只允许具有RESTRICTED SESSION权限的用户(如sys用户)访问数据库。
STARTUP RECOVER:数据库启动,并开始介质恢复。
2)SHUTDOWN
SHUTDOWN NORMAL:缺省不带任何参数时表示是NORMAL。不允许新的连接、等待会话结束、等待事务结束、做一个检查点并关闭数据文件。启动时不需要实例恢复。
SHUTDOWN TRANSACTIONAL:不允许新的连接、不等待会话结束、等待事务结束、做一个检查点并关闭数据文件。启动时不需要实例恢复。
SHUTDOWN IMMEDIATE:不允许新的连接、不等待会话结束、不等待事务结束、做一个检查点并关闭数据文件。没有结束的事务是自动rollback的。启动时不需要实例恢复。 SHUTDOWN ABORT:不允许新的连接、不等待会话结束、不等待事务结束、不做检查点且没有关闭数据文件。启动时自动进行实例恢复。
有以下几种启动方式:
1、startup nomount
非安装启动,这种方式启动下可执行:重建控制文件、重建数据库
读取init.ora文件,启动instance,即启动SGA和后台进程,,这种启动只需要init.ora文件。
这种过程又称为:非安装启动
启动过程为:启动Oracle实例,不加载数据库,不打开数据库。在这个过程中只需要init.ora初始化参数文件,重建控制文件,即启动SGA和后台进程
在以下几种情况下需要用到这种模式:
A:数据库的控制文件全部损害
B:需要创建数据库的控制文件和创建一个新的数据库时。
2、startup mount dbname
安装启动,这种方式启动下可执行:
数据库日志归档、
数据库介质恢复、
使数据文件联机或脱机,
重新定位数据文件、重做日志文件。
执行“nomount”,然后打开控制文件,确认数据文件和联机日志文件的位置,
但此时不对数据文件和日志文件进行校验检查。
这种过程又被成为:安装启动
启动过程:打开控制文件,确认数据文件和联机日志文件的位置,但此时不对数据文件和日志文件进行一致性,正确性等校验检查。
在以下几种情况下需要用到这种模式:
A:数据库归档日志
B:数据库介质恢复
C:使数据文件联机或脱机
D:重新定位数据文件、重做日志文件

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