Alter Dtabase Close

[Sonia]

Hi folks,
What is the use of 'ALTER DTABASE CLOSE' command
This command brings the instance from OPEN state to MOUNT state.

But from mount it is not possible to go back to open......i think it is a bug...........

Is this the only use or is there any other use?

Regards
sonia

[marist89]

Originally posted by Sonia

But from mount it is not possible to go back to open......i think it is a bug...........

How about ALTER DATABASE OPEN ?

Sometimes you may need to bring your database to mount mode for some maintenance. Instead of shutting it down and bringing it up in mount mode, you can use ALTER DATABASE CLOSE.

[vinit]

Once closed, the database is in mount state but cannot be opened from there on. You need to shut it down to open it, atleast on 817.
Here's the detail -

SVRMGR> startup ;
ORACLE instance started.
Total System Global Area 156633116 bytes
Fixed Size 75804 bytes
Variable Size 44003328 bytes
Database Buffers 112476160 bytes
Redo Buffers 77824 bytes
Database mounted.
Database opened.
SVRMGR> alter database close;
Statement processed.
SVRMGR> select status from v$instance;
STATUS
-------
MOUNTED
1 row selected.
SVRMGR> alter database open;
alter database open
*
ORA-01531: a database already open by the instance
SVRMGR> select status from v$instance;
STATUS
-------
MOUNTED
1 row selected.
SVRMGR> startup open;
ORA-01081: cannot start already-running ORACLE - shut it down first
SVRMGR> shutdown;
ORA-01109: database not open
Database dismounted.
ORACLE instance shut down.
SVRMGR> startup;
ORACLE instance started.


Here's the fun part..although it says database closed, when u say "alter database open" oracle says db is already open.

[jmodic]

Yep, this behavior has stil not been changed in 9i, at least not in 9.0.1.