Oracle start-Up and shutdown

First, Sql*plus way:

use Sql*plus to connect toOracle

Sqlplus/nolog starts Sql*plus without connecting to the database

Connect/as SYSDBA is connected to Oracle as DBA

Startup is ready to start.

However, there are 3 types of Oracle Boot modes:

L startup Nomount (Nomount mode) Boot instance does not load the database.

L startup mount (Mount mode) Launch instance load database without opening database

L Startup (open mode) starts the instance load and opens the database, which is the command we used above

In Nomount mode, Oracle creates a variety of memory structures and service processes for instances and does not open any database files.

So:

1) Create a new database

2) Rebuilding the control file

All 2 of these operations must be done in this mode.

In Mount mode, Oracle mounts only the database but does not open the database, so says:

1) renaming the data file

2) Add, remove, and rename redo days files

3) perform a full database restore operation

4) Change the archive mode of the database

All 4 of these operations must be performed in this mode

Open mode (which is our startup without any parameters) starts normally.

Of course these 3 modes can be converted between:

Alter database mount (nomount mode)-〉alter database open (Mount mode)-〉 (open mode)

Of course there are other situations where the database can be set to unrestricted and restricted in our open mode

In a restricted state, only the DBA can access the database, so say:

1) perform data import and export

2) extract external data using Sql*loader

3) need to temporarily deny ordinary users access to the database

4) perform database porting or upgrade operations

All 4 of these operations must be performed in this state.

Use the startup restrict command to enter a restricted state when you open a database. use the ALTER system disable restricted session command to change the restricted state to an unrestricted state. Usealter system enable restricted session command to change unrestricted state to restricted state

Use the ALTER DATABASE open read only to bring the databases into a read-only state.
Use the ALTER DATABASE open read write to put the databases into read-write state.

Of course, in some cases it may not be possible to start the database successfully using the various startup methods mentioned above, this time use the Startup Force command to start the database forcibly. Of course no one wants to run into this situation:)

C. Closing a database
1) normal shutdown shutdown
2) immediately close shutdown immediate
3) Close transaction shutdown transactional
4) forcibly close shutdown abort, of course no one wants to run into this situation.

Oracle start-Up and shutdown