Different Shut Down Commands

Oracle Database can be shut down with shut down oracle command. For this you may need to apply the different versions of this command in different situations.

Shutting Down with the NORMAL Clause

First you connect to the database server as SYSOPER or SYSDBA. How can you do this? Open you SQL *Plus. Then you will write sys as sysdba beside Enter user-name:  and you will give password and finally press Enter. As a result, you can be connected to the Oracle Database. 

This normal clause is optional since this is the default shutdown method if no clause is provided. Normal database shutdown proceeds with the following conditions:

i)No new connections are permitted after the statement is issued.

ii) Before the database is shut down, the database waits for all currently connected users to disconnect from the database.

iii) The next start up of the database will not require any instance recovery procedures. 

Shutting Down with the IMMEDIATE Clause

To shut down a database immediately, please use the SHUTDOWN command with the IMMEDIATE clause:

SQL>SHUTDOWN IMMEDIATE

The immediate shutdown has following conditions:

i)No new connections are allowed, nor are new transactions permitted to be started, after the statement is issued. 

ii) Any uncommitted transactions are rolled back. 

iii)Oracle database doesn't wait for users currently connected to the database to disconnect. The database implicitly rolls back active transactions and disconnects all connected users.

iv) The next startup of the database will not require any instance recovery procedures. 

Use immediate database shutdown only in the following situations: 

• To initiate an automated & unattended backup
• When a power shutdown is going to occur soon
• when the database or one of its applications is functioning unevenly and you can't contact users to ask them to log off or they are unable to log off. 

Shutting Down with the TRANSACTIONAL clause

When you want to execute a planned shutdown of an instance,  use the SHUTDOWN command with the TRANSNATIONAL clause while permitting active transactions to complete first.

SQL>SHUTDOWN TRANSACTIONAL 

Transactional database has the following conditions:

• No new connections are allowed, nor are new transactions allowed to be started, after the statement is issued. 
• After all transactions have completed, any client still connected to the instance is disconnected. 
• At this point, the instance shuts down just as it would when a SHUTDOWN IMMEDIATE statement is submitted. 
• The next startup of the database will not need any instance recovery procedures. 
• A transactional shutdown prevents clients from losing work, and at the same time, doesn't require all users to log off. 

Shutting Down with the ABORT Clause

You can also shut down your database using ABORT Clause by the following command: 

SQL>SHUTDOWN ABORT

An aborted database shutdown proceeds with the following conditions:

• No new connections are allowed, nor are new transactions allowed to be started, after the statement is issued. 
• Current client SQL statements being processed by Oracle Database are immediately terminated.
• Uncommitted transactions are not rolled back.
• Oracle database doesn't wait for users currently connected to the database to disconnect. The database implicitly disconnects all connected users. 
• The next startup of the database will need instance recovery procedures. 

You can shut down a database instantaneously by aborting the database instance. If it is possible, please perform this type of shutdown only in the following situations:

• The database or one of its applications is functioning irregularly and none of the other types of shutdown works.
• You need to shut down the database instantaneously( As for example, if you know a power down is going to occur in one minute).
• You experience problems while starting a database instance.