Summary of how Oracle databases are started and closed

oracle| Data | database
How Oracle databases are started and closed

First, several start-up ways:

1, Startup Nomount
Non-installation startup, this way to launch executable: Rebuild control file, rebuild database
Start instance, that is, start the SGA and background processes, which only require Init.ora files.
2, startup Mount DBName
Install startup, this way to start under executable: Database log archiving, database recovery, renaming some database files
such as: system table space or log file.
Execute "nomount" and then open the control file
3, Startup Open dbname
Execute "nomount" first, then "Mount", and then open all the database files, including the redo log file,
In this way, the data in the database can be accessed.
4, startup, equal to the following three orders
Startup Nomount
ALTER DATABASE Mount
ALTER DATABASE Open
5, startup restrict
Constraint start
This way the database can be started, but only users with certain privileges are allowed to access
When an unprivileged user accesses, the following prompts appear:
ERROR:
Ora-01035:oracle only allow users with restricted session permissions to use
6, Startup force
Forced start mode
When you cannot close the database, you can use startup force to complete the shutdown of the database
Close the database before performing the normal start database command
7, startup pfile= parameter filename
Startup method with initialization parameter file
Read the parameter file first, then start the database by setting in the parameter file
Example: Startup Pfile=e:\oracle\admin\oradb\pfile\init.ora
8, startup EXCLUSIVE

Two, several close way:

1. Shutdown normal
Shut down the database in the normal way.
2, Shutdown immediate
Close the database immediately.
Shutdown immediate is executed in SVRMGRL, the database is not immediately closed,
Instead of shutting down (terminating the session, releasing the session resource) after Oracle performs some cleanup work,
When you cannot close a database using shutdown, shutdown immediate can complete the operation of the database shutdown.
3, Shutdown abort
Close the database directly, the session that is accessing the database will be abruptly terminated,
If a large number of operations in the database are in progress, it will take a long time to restart the database after performing shutdown abort.