1. Platform Guide
  2. Oracle Database Specifications for Windows
  3. Overview of Initialization Parameter File

15.1 Overview of Initialization Parameter File

An initialization parameter file is an ASCII text file containing parameters.

By changing parameters and values in an initialization parameter file, you can specify, for example:

  • Amount of memory Oracle Database uses

  • Whether to archive filled online redo logs

  • Which control files currently exist

Every database instance has a corresponding initialization parameter file and an ORACLE_SID registry parameter that points to the system identifier for the instance.

The initialization parameter file name takes the form init.ora. A single instance might have several initialization parameter files, each having some differences that affect system performance.

Note:

Your init.ora file for initialization parameters is set by Oracle Universal Installer during database installation. These parameter settings may vary depending on your hardware configuration.

Topics:

See Also:

Oracle Database Reference for descriptions of all initialization parameters and instructions for setting and displaying their values

15.1.1 About the Location of the Initialization Parameter File

Describes the location of the initialization parameter file.

If you do not specify a different initialization file with the option PFILE at database startup, then by default Oracle Database uses initialization parameter files located in 

ORACLE_HOME\Database\init.ora

Note:

If you create a database manually using an SQL script, then you are required to create an initialization parameter file or copy an existing initialization parameter file and modify the contents. If you use Database Configuration Assistant to create a database, then the initialization parameter file is automatically created for you.

15.1.2 About Editing The Initialization Parameter File

To customize Oracle Database functions, you may be required to edit the initialization parameter file.

Use only an ASCII text editor to modify the file.

15.1.3 About Oracle Database Configuration Assistant Renaming init.ora

When you create a database using Oracle Database Configuration Assistant (Oracle DBCA), a Server Parameter File (SPFILE) is created from the initialization parameter file, and the initialization parameter file is renamed.

Oracle does not recognize the renamed file as an initialization parameter file, and it is not used after the instance is started.

If you want to modify an instance created with Oracle DBCA after it starts, you must use theALTER SYSTEM statement. You cannot change the Server Parameter File itself, because it is a binary file that cannot be browsed or edited using a text editor. The location of the newly-created Server Parameter File is ORACLE_HOME\database. The Server Parameter File file name is spfileSID.ora.

See Also:

Oracle Database Administrator's Guide