Oracle数据库的四种状态

SHUTDOWN-->NOMOUNT-->MOUNT-->OPEN

SHUTDOWN-->NOMOUNT：Instance started

NOMOUNT-->MOUNT：Control file opened for this instance

MOUNT-->OPEN：ALL files opened as described by this control file for this instance

启动的过程：

[oracle@mylinux spba]$ sqlplus /nolog

SQL*Plus: Release 10.2.0.1.0 - Production on Wed Apr 15 21:15:04 2009

Copyright (c) 1982, 2005, Oracle.  All rights reserved.

SQL> conn / as sysdba
Connected to an idle instance.
SQL> startup nomount
ORACLE instance started.

Total System Global Area  285212672 bytes
Fixed Size                  1218992 bytes
Variable Size             109053520 bytes
Database Buffers          171966464 bytes
Redo Buffers                2973696 bytes
SQL> alter database mount;

Database altered.

SQL> alter database open;

Database altered.

SQL>