Oracle Database startup and shutdown methods, oracle Database

Oracle Database startup and shutdown methods, oracle Database

I. Oracle Database startup Methods

(1) startup nomount

Non-installation startup. In this mode, you can execute re-build the control file, re-build the database, and read the init. ora file, start the instance, that is, start the SGA and background processes. ora file.

(2) startup mount (dbname)

Install and start. In this mode, you can run the following commands: Database Log archiving, database media recovery, online or offline data files, data file locating, and redo log files.

Execute "nomount", open the control file, and confirm the location of the data file and the on-line log file. However, the data file and log file are not verified at this time.

(3) startup open (dbname)

Run "nomount" first, then "mount", and then open all database files including Redo log files. In this way, you can access data in the database.

(4) startup is equal to the following three commands:

Startup nomount

Alter database mount

Alter database open

(5) startup restrict

Constraint-based startup. This method can start the database, but only allow access by users with certain privileges. When a non-privileged user accesses the database, the following prompt appears:

ERROR: ORA-01035: ORACLE only allows users with restricted session Permissions

(6) startup force

Forced start mode. When the database cannot be closed, you can use startup force to close the database. First, close the database and then execute the commands to start the database normally.

(7) startup pfile = parameter file name

The startup method with the initialization parameter file. Read the parameter file first, and then start the database according to the settings in the parameter file.

Example: startuppfile = E: \ Oracle \ admin \ oradb \ pfile \ init. ora

(8) startupEXCLUSIVE

Exclusive and shared startup

Ii. Three Oracle shutdown Methods

(1) shutdown normal

Close the database normally

(2) shutdownimmediate

Immediately shut down the database and execute shutdownimmediate in SVRMGRL. The database is not closed immediately, but is closed only after Oracle executes some cleanup tasks (terminate the session and release the session resources ).

When shutdown cannot shut down the database, shutdownimmediate can be used to close the database.

(3) shutdown abort

Directly shut down the database, and the session accessing the database will be suddenly terminated. If a large number of operations are being performed in the database, it will take a long time to restart the database after the shutdown abort is executed.