Initialization Parameter File

The initialization parameter file is a text file that contains a list of parameters and a value for each parameter. The file should be written in the client's default character set. Specify values in the parameter file that reflect your installation.

The following are sample entries in a parameter file:

PROCESSES = 100
OPEN_LINKS = 12
GLOBAL_NAMES = true

The name of the parameter file varies depending on the operating system. For example, it can be in mixed case or lowercase, or it can have a logical name or a variation of the name INIT.ORA. Also supplied is an INITDW.ORA file, which contains suggested parameter settings for data warehouses and data marts. As the database administrator, you can choose a different filename for your parameter file.

Refer to your operating system-specific Oracle documentation for the default locations and filenames for these parameter files. The initialization parameter file is read by the client-side tool you use to start the server (such as SQL*Plus).

Sample parameter files are provided on the Oracle server distribution medium for each operating system. A sample file is sufficient for initial use, but you will probably want to modify the file to tune the database system for best performance. Any changes will take effect after you completely shut down the instance and then restart it.

Database administrators can use initialization parameters to

• Optimize performance by adjusting memory structures, such as the number of database buffers in memory

• Set some database-wide defaults, such as the amount of space initially allocated for a context area when it is created

• Set database limits, such as the maximum number of database users

• Specify names of files

Many initialization parameters can be fine-tuned to improve database performance. Other parameters should never be altered or should be altered only under the supervision of Oracle Support Services.