1 状态查询
2 实验过程
SQL> startup nomount;
Total System Global Area 125829120 bytes
Fixed Size 1247684 bytes
Variable Size 92276284 bytes
Database Buffers 25165824 bytes
Redo Buffers 7139328 bytes
SQL> select status from v$instance;
STATUS
------------
STARTED
SQL> select open_mode from v$database;
select open_mode from v$database
*
ERROR at line 1:
ORA-01507: database not mounted
SQL> alter database mount;
Database altered.
SQL> select status from v$instance;
STATUS
------------
MOUNTED
SQL> select open_mode from v$database;
OPEN_MODE
----------
MOUNTED
SQL> alter database open;
Database altered.
SQL> select status from v$instance;
STATUS
------------
OPEN
SQL> select open_mode from v$database;
OPEN_MODE
----------
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