启动实例：

$ ls $ORACLE_HOME/dbs/spfileorcl.ora

Strings  ORACLE_HOME/dbs/spfileorcl.ora

SQL> shutdown immediate

SQL> startup nomount

SQL> select status from v$instance;

SQL> select * from v$sgainfo;

SQL> select * from hr.employees;

SQL> conn hr/hr

SQL> startup mount或alter database mount;

SQL> show parameter control_files

SQL> select status from v$instance;检查实例状态

SQL> select * from v$controlfile;动态性能视图

SQL> select name from v$datafile;

SQL> select * from hr.employees;

SQL> conn hr/hr

SQL> startup或alter database open;

SQL> select status from v$instance;

SQL> select * from hr.employees;

SQL> conn hr/hr

数据库启动步骤