1. 后台进程 dbwr 数据库写进程。lgwr 日志写进程。ckpt 检查点写进程。smon 系统监控进程。 pmon进程监控进程。 arch归档进程。 reco 恢复进程。 lckn 封锁进程。 2.DBA命令执行方式 sqldba mode=line 或 sqldba lmode=y 然后 SQLDBA 输入行命令 3.oracle
1. 后台进程
dbwr 数据库写进程。lgwr 日志写进程。ckpt 检查点写进程。smon 系统监控进程。 pmon进程监控进程。
arch归档进程。 reco 恢复进程。 lckn 封锁进程。
2.DBA命令执行方式
sqldba mode=line 或 sqldba lmode=y 然后 SQLDBA> 输入行命令
3.oracle 特殊用户:
(1)internal: 只能在服务器端使用的超级用户,它具有DBA的所有特权。4.
(2)system(manager):显示管理信息的视图,和oracle工具所使用的所以视图。
(3)sys(change_on_install) 只能在服务器端使用的超级用户。
4.启动数据库
(1)启动参数和约束条件
Exclusive/Parallel:专用/并行数据库模式。
Database Name:要启动的数据库名,默认值为ORACLE_SID变量的值。
Parameter File:在启动实例时,访问的参数文件名,默认文件为initSID.ora。Force:在启动实例前,强行关闭当前实例。
Restrict to DBAs:数据库启动后,只有DBA特权的用户才能访问数据库。
Recover:在启动实例时,用日志文件做数据库恢复(2)用行命令启动数据库:
sqldba mode=line
sqldab>connect internal
sqldba>startup
5.关闭方式
(1)Normal 处理完用户提交的所有事务,等带用户退出连接后,关闭数据库、卸载数据库、关闭实例。在下次启动实例时,不做实例恢复操作。
(2)Immediate/ Abort Instance结束正在处理的SQL语句、回滚未提交事务、不等待用户退出正常连接。在下次启动实例时,做实例恢复操作rmal处理完用户提交的
所有事务,等待用户退出连接后,关闭数据库、卸载数据库、关闭实例。在下次启动实例时,不做实例恢复操作。
(3)用命令行关闭数据库 sqldba mode=line sqldba>connect internal sqldba>shutdown
6.用户管理:
(1)添加用户:
CREATE USER 用户名 INDENTIFIED BY 口令
EXTERNALLY
DEFAULT TABLESPACE 表空间名
TEMPORARY TABLESPACE 表空间名
QUOTA 整数 K/M ON 表空间名
UNLIMITED
PROFILE 环境文件名例:
CREATE USER sidney INDENTIFIED BY carton
DEFAULT TABLESPACE cases_ts
TEMPORARY TABLESPACE temp_ts
QUOTA 5M ON cases_ts
QUOTA 5M ON temp_ts
PROFILE engineer
建立按操作系统帐号george可存取的用户。
CREATE USER OPS$georage
INDENTIFIED EXTERNALLY
DEFAULT TABLESPACE accs_ts
TEMPORARY TABLESPACE temp_ts
QUOTA UNLIMITED ON accs_ts
QUOTA UNLIMITED ON temp_ts(2)删除用户:
DROP USER 用户名 CASCADE
(3)与用户管理有关的数据字典视图
?USER_USERS
? ALL_USERS
? DBA_USERS
? USER_TS_QUOTAS
6.环境文件管理
?Sessions/User:限制一个用户的并发会话个数。
?CPU Time/Session :限制一次会话的CPU时间,单位:百分之一秒。
?CPU Time/Call:限制一次调用(一次语法分析、执行或获得)的CPU时间,单位:百分之一秒。
?Connect Time:限制一会话总的使用时间,单位:分。
?Logical Reads/Session:限制在一次会话中读的数据块的数目,包括从内存或磁盘读的块数。
?Logical Reads/Call:限制处理一个SQL语句(语法分析、执行和获取)一次调用所读的数据块的数目。
?Private SGA/Session:限制一次会话在SGA的共享池可分配的专用空间的数目,单位:bytes/Kbytes/Mbytes。
? Composite Limit:一次会话总的资源开销,以服务单位表示该参数的值。
删除环境文件
DROP PROFILE环境文件名CASCADE

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