Startup and Shutdown stages
Before starting the instance we need to set instance name to be opened at os prompt
$export ORACLE_SID=<sid>
Before starting the instance we need to set instance name to be opened at os prompt
$export ORACLE_SID=<sid>
Sid = instance name
SQL> startup
ORACLE instance started.
Total System Global Area 251658240 bytes
Fixed Size 788368 bytes
Variable Size 145750128 bytes
Database Buffers 104857600 bytes
Redo Buffers 262144 bytes
Database mounted.
Database opened.
When Oracle is trying to open your database, it goes through three distinct stages, and each of these is listed in the startup output listed previously. These stages are:
The Startup (nomount) Stage
During the nomount stage, Oracle first opens and reads the initialization parameter file (init.ora) to see how the database is configured
* Startup (nomount)
There are some types of Oracle recovery operations that require the database to be in nomount stage.
SQL> startup nomount
The Mount Stage
When the startup command enters the mount stage, it opens and reads the control fil
SQL> startup mount
If you have already started the database instance with the startup nomount command, you might change it from the nomount to mount startup stage using the alter database command:
SQL> alter database mount;
The Open Oracle startup Stage
To open the database, you can just use the startup command as seen in this example
SQL> startup
If the database is mounted, you can open it with the alter database open command as seen in this example:
SQL> alter database open;
Shutting Down a Database
To shut down a database and instance, you must first connect as SYSOPER or SYSDBA.
· Shutting Down with the NORMAL Clause
· Shutting Down with the IMMEDIATE Clause
· Shutting Down with the TRANSACTIONAL Clause
· Shutting Down with the ABORT Clause
Shutting Down with the NORMAL Clause
To shut down a database in normal situations, use the SHUTDOWN command with the NORMAL clause:
SQL> startup
ORACLE instance started.
Total System Global Area 251658240 bytes
Fixed Size 788368 bytes
Variable Size 145750128 bytes
Database Buffers 104857600 bytes
Redo Buffers 262144 bytes
Database mounted.
Database opened.
When Oracle is trying to open your database, it goes through three distinct stages, and each of these is listed in the startup output listed previously. These stages are:
The Startup (nomount) Stage
During the nomount stage, Oracle first opens and reads the initialization parameter file (init.ora) to see how the database is configured
* Startup (nomount)
There are some types of Oracle recovery operations that require the database to be in nomount stage.
SQL> startup nomount
The Mount Stage
When the startup command enters the mount stage, it opens and reads the control fil
SQL> startup mount
If you have already started the database instance with the startup nomount command, you might change it from the nomount to mount startup stage using the alter database command:
SQL> alter database mount;
The Open Oracle startup Stage
To open the database, you can just use the startup command as seen in this example
SQL> startup
If the database is mounted, you can open it with the alter database open command as seen in this example:
SQL> alter database open;
Shutting Down a Database
To shut down a database and instance, you must first connect as SYSOPER or SYSDBA.
· Shutting Down with the NORMAL Clause
· Shutting Down with the IMMEDIATE Clause
· Shutting Down with the TRANSACTIONAL Clause
· Shutting Down with the ABORT Clause
Shutting Down with the NORMAL Clause
To shut down a database in normal situations, use the SHUTDOWN command with the NORMAL clause:
SHUTDOWN NORMAL
The NORMAL clause is optional, because this is the default shutdown method if no clause is provided.
Normal database shutdown proceeds with the following conditions:
· No new connections are allowed after the statement is issued.
· Before the database is shut down, the database waits for all currently connected users to disconnect from the database.
The next startup of the database will not require any instance recovery procedures.
Shutting Down with the IMMEDIATE Clause
Immediate 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.
· Any uncommitted transactions are rolled back. (If long uncommitted transactions exist, this method of shutdown might not complete quickly, despite its name.)
· Oracle Database does not wait for users currently connected to the database to disconnect. The database implicitly rolls back active transactions and disconnects all connected users.
The next startup of the database will not require any instance recovery procedures.
Shutting Down with the TRANSACTIONAL Clause
When you want to perform a planned shutdown of an instance while allowing active transactions to complete first, use the SHUTDOWN command with the TRANSACTIONAL clause:
The NORMAL clause is optional, because this is the default shutdown method if no clause is provided.
Normal database shutdown proceeds with the following conditions:
· No new connections are allowed after the statement is issued.
· Before the database is shut down, the database waits for all currently connected users to disconnect from the database.
The next startup of the database will not require any instance recovery procedures.
Shutting Down with the IMMEDIATE Clause
Immediate 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.
· Any uncommitted transactions are rolled back. (If long uncommitted transactions exist, this method of shutdown might not complete quickly, despite its name.)
· Oracle Database does not wait for users currently connected to the database to disconnect. The database implicitly rolls back active transactions and disconnects all connected users.
The next startup of the database will not require any instance recovery procedures.
Shutting Down with the TRANSACTIONAL Clause
When you want to perform a planned shutdown of an instance while allowing active transactions to complete first, use the SHUTDOWN command with the TRANSACTIONAL clause:
SHUTDOWN TRANSACTIONAL
Transactional 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.
· 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 require any instance recovery procedures.
Shutting Down with the ABORT Clause
You can shut down a database instantaneously by aborting the database instance.
When you must do a database shutdown by aborting transactions and user connections, issue the SHUTDOWN command with the ABORT clause:
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 does not wait for users currently connected to the database to disconnect. The database implicitly disconnects all connected users
Transactional 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.
· 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 require any instance recovery procedures.
Shutting Down with the ABORT Clause
You can shut down a database instantaneously by aborting the database instance.
When you must do a database shutdown by aborting transactions and user connections, issue the SHUTDOWN command with the ABORT clause:
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 does not wait for users currently connected to the database to disconnect. The database implicitly disconnects all connected users
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