Shutdown modes are progressively more accommodating of current activity in this order:
• ABORT: Performs the least amount of work before shutting down. Because this
requires recovery before startup, use this only when necessary. This is typically used
when no other form of shutdown works, when there are problems when starting the
instance, or when you need to shut down immediately because of an impending
situation, such as notice of a power outage within seconds.
• IMMEDIATE: Is the most typically used option. Uncommitted transactions are rolled
back.
• TRANSACTIONAL: Allows transactions to finish
• NORMAL: Waits for sessions to disconnect
If you consider the amount of time that it takes to perform the shutdown, you find that
ABORT is the fastest and NORMAL is the slowest.
SHUTDOWN Options
SHUTDOWN NORMAL
Normal is the default shutdown mode. A normal database shutdown proceeds with the
following conditions:
• No new connections can be made.
• The Oracle server waits for all users to disconnect before completing the shutdown.
• Database and redo buffers are written to disk.
• Background processes are terminated and the SGA is removed from memory.
• The Oracle server closes and dismounts the database before shutting down the
instance.
• The next startup does not require an instance recovery.
SHUTDOWN TRANSACTIONAL
A transactional shutdown prevents clients from losing data, including the results from their
current activity. A transactional database shutdown proceeds with the following
conditions:
• No client can start a new transaction on this particular instance.
• A client is disconnected when the client ends the transaction that is in progress.
• When all transactions have been completed, a shutdown occurs immediately.
• The next startup does not require an instance recovery.
SHUTDOWN IMMEDIATE
Immediate database shutdown proceeds with the following conditions:
• Current SQL statements being processed by the Oracle database are not completed.
• The Oracle server does not wait for the users who are currently connected to the
database to disconnect.
• The Oracle server rolls back active transactions and disconnects all connected users.
• The Oracle server closes and dismounts the database before shutting down the
instance.
• The next startup does not require an instance recovery.
• ABORT: Performs the least amount of work before shutting down. Because this
requires recovery before startup, use this only when necessary. This is typically used
when no other form of shutdown works, when there are problems when starting the
instance, or when you need to shut down immediately because of an impending
situation, such as notice of a power outage within seconds.
• IMMEDIATE: Is the most typically used option. Uncommitted transactions are rolled
back.
• TRANSACTIONAL: Allows transactions to finish
• NORMAL: Waits for sessions to disconnect
If you consider the amount of time that it takes to perform the shutdown, you find that
ABORT is the fastest and NORMAL is the slowest.
SHUTDOWN Options
SHUTDOWN NORMAL
Normal is the default shutdown mode. A normal database shutdown proceeds with the
following conditions:
• No new connections can be made.
• The Oracle server waits for all users to disconnect before completing the shutdown.
• Database and redo buffers are written to disk.
• Background processes are terminated and the SGA is removed from memory.
• The Oracle server closes and dismounts the database before shutting down the
instance.
• The next startup does not require an instance recovery.
SHUTDOWN TRANSACTIONAL
A transactional shutdown prevents clients from losing data, including the results from their
current activity. A transactional database shutdown proceeds with the following
conditions:
• No client can start a new transaction on this particular instance.
• A client is disconnected when the client ends the transaction that is in progress.
• When all transactions have been completed, a shutdown occurs immediately.
• The next startup does not require an instance recovery.
SHUTDOWN IMMEDIATE
Immediate database shutdown proceeds with the following conditions:
• Current SQL statements being processed by the Oracle database are not completed.
• The Oracle server does not wait for the users who are currently connected to the
database to disconnect.
• The Oracle server rolls back active transactions and disconnects all connected users.
• The Oracle server closes and dismounts the database before shutting down the
instance.
• The next startup does not require an instance recovery.
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