One of the most common jobs of the database administrator is to startup or shutdown the Oracle database. To start an instance, the database must read the initialization parameters or SPFILE. When you issue the SQL*Plus STARTUP command, the database attempts to read the initialization parameters from an SPFILE in a platform-specific default location. If it finds no SPFILE, it searches for a text initialization parameter file.
In the platform-specific default location, Oracle Database locates your initialization parameter file by examining filenames in the following order:
- spfileSID.ora
- spfile.ora
- initSID.ora
You start the Oracle database with the startup command. You must first be logged into an account that has sysdba or sysoper privileges. DBA connecting to the database and starting the instance:
[oracle10@localhost ~]$ export_SID=dbn
[oracle10@localhost ~]$ aqlplus "/as sysdba"
SQL*Plus: Release 10.2.0.1.0 - Production on Wed Nov 9 14:18:33 2011
Copyright (c) 1982, 2005, Oracle. All rights reserved
Connected to an idle instance
SQL> startup
ORACLE instance started.
Total System Global Area 314572800 bytes
Fixed Size 1219160 bytes
Variable Size 96470440 bytes
Database Buffers 213909504 bytes
Redo Buffers 2973696 bytes
Database mounted.
Database opened.
SQL>
We set the ORACLE_SID to the name of the database and we log into SQL*Plus using the “sys as sysdba” login. This gives us the privileges we need to be able to startup the database. Finally, after we enter our password, we issue the startup command to startup the database. Oracle displays its progress as it opens the database, and then returns us to the SQL*Plus prompt once the startup has been completed. When Oracle is trying to open your database, it goes through three distinct stages.These stages are
0 comments:
Post a Comment