B
Oracle8i Database Specifications for Windows NT

Oracle8i Enterprise Edition uses initialization parameters to enable various features of the database every time an instance is started.

Specific topics discussed are:

• Initialization Parameter File (INIT.ORA) Overview
• Initialization Parameters
• Calculating Database Limits

Initialization Parameter File (INIT.ORA) Overview

An initialization parameter file is an ASCII text file containing parameters. By changing the parameters and values in an initialization file, you can specify, for example:

• the amount of memory the database uses
• whether to archive filled online redo logs
• which control files currently exist for the database

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

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

Additional Information: See Oracle8i Reference for a complete list and descriptions of all initialization parameters.

Location of the Initialization Parameter File

By default, Oracle8i Enterprise Edition uses the initialization parameter files located in ORACLE_BASE\ADMIN\DB_NAME\PFILE, unless you specify a different initialization file with the PFILE option at database startup.

Editing the Initialization Parameter File

To customize Oracle8i database functions, you may need to edit the initialization parameter files. Use any ASCII text editor to modify the file.

Sample File

A sample file called INITSMPL.ORA is located in the ORACLE_HOME \DATABASE directory.

Note: If you create a database manually using the BUILD_DB.SQL script, you need to create an INIT.ORA file or copy an existing INIT.ORA file and modify the contents. If you use Oracle Database Configuration Assistant to create a database, the INIT.ORA file is automatically created for you.

If you want to use the sample INITSMPL.ORA file as part of database creation:

1. Rename the file INIT.ORA.

2. Edit this file to reflect the correct location of your database files and the name of your database.

If you installed a starter database, the initialization parameter file INIT.ORA used by the starter database is located in ORACLE_BASE\ADMIN\DB_NAME\PFILE. You can use either INITSMPL.ORA or the starter database INIT.ORA as a basis for creating a new Oracle8 database initialization parameter file.

The annotated, sample initialization parameter file contains alternative values for the initialization parameters. These values and the annotations are preceded by comment signs (#), which prevent them from being processed. To activate a particular parameter, remove the preceding # sign. When you no longer want to use a particular parameter, edit the initialization parameter file to add a comment sign.

For example, several initialization parameters are specified with three different values to create small, medium, or large System Global Areas (SGAs), respectively. The parameter that creates a small SGA is active in the following example:

  db_block_buffers = 200                 # SMALL 

# db_block_buffers = 550                   # MEDIUM 

# db_block_buffers = 3200                  # LARGE

To create a medium-sized SGA, comment out the small parameter definition and activate the medium parameter definition. Edit the initialization parameter file as follows:

# db_block_buffers = 200                 # SMALL 

  db_block_buffers = 550                   # MEDIUM 

# db_block_buffers = 3200                  # LARGE

Initialization Parameters

Oracle8i Reference includes descriptions of all initialization parameters and instructions for setting and displaying their values. The following table describes initialization parameters and default values for Oracle8i Enterprise Edition for Windows NT.

Initialization Parameter Name	Default Value	Range of Values
AUDIT_TRAIL	NONE	NONE (FALSE),  DB (TRUE), OS
BACKGROUND_DUMP_DEST	%ORACLE_BASE%\ADMIN\DB_NAME\BDUMP	Any valid directory
COMPATIBLE	8.1.5.0.0	Default release to current release
COMMIT_POINT_STRENGTH	1	0 - 255
CONTROL_FILES	%ORACLE_BASE%\ORADATA\DB_NAME\CONTROL01.CTL or \CONTROL02.CTL	Any valid path and filename
DB_BLOCK_BUFFERS	1000	1000 to 4 GB
DB_BLOCK_SIZE	2048	2048 - 163841
DB_FILES	1024	65,536 files2
DB_FILE_MULTIBLOCK_ READ_ COUNT3	8	1 - 324
DB_NAME	ORCLx	Any valid database name limited to a maximum of eight characters.
DISTRIBUTED_TRANSACTIONS	5 * TRANSACTIONS	0 - 75 TRANSACTIONS
DML_LOCKS	300	20- unlimited
JOB_QUEUE_INTERVAL	60	1 - 3600
JOB_QUEUE_PROCESSES	2	0 - 36
LOG_ARCHIVE_DEST	%ORACLE_BASE%\ORADATA\DB_NAME\ARCHIVE	Any valid directory
LOG_ARCHIVE_FORMAT	"%%DB_NAME%%T%TS%S.ARC"	A valid filename format
LOG_ARCHIVE_START	None	TRUE or FALSE
LOG_CHECKPOINT_ INTERVAL	10,000	2 - Unlimited
LOG_CHECKPOINT_ TIMEOUT	0	0 - Unlimited
LOG_FILES	255	2 - 255
LOG_BUFFER	32768	163840
MAX_DUMP_FILE_SIZE	10240	0 to 5 MB
MTS_DISPATCHERS	Unspecified5	User specific
MTS_MAX_DISPATCHERS	5	User specific
MTS_MAX_SERVERS	20	User specific
MTS_SERVERS	0	User specific
NLS_LANGUAGE	AMERICAN	Any valid language
NLS_SORT	(Language dependent)	(Language dependent)
NLS_TERRITORY	AMERICA	Any valid territory
OPEN_CURSORS	50	1 - Unlimited
OPEN_LINKS	4	0 - 255
OS_AUTHENT_PREFIX	OPS$	Any character string
PROCESSES	59	6 - Unlimited
REMOTE_LOGIN_ PASSWORDFILE	NONE	SHARED, EXCLUSIVE, NONE
SHARED_POOL_SIZE	15,728,640	300 KB - Unlimited
SORT_AREA_SIZE	65536	0 - Unlimited
TEXT_ENABLE	TRUE	TRUE or FALSE
TIMED_STATISTICS	FALSE	TRUE or FALSE
TRANSACTIONS_PER_ROLLBACK_SEGMENT	5	1 - 255
USER_DUMP_DEST	%ORACLE_BASE%\ADMIN\DB_NAME\UDUMP	Any valid directory

1 The Range of Values for DB_BLOCK_SIZE on a 7.3.x database is 512 to 8192. 2 See Section , "Calculating Database Limits" for more information. 3 The DB_FILE_MULTIBLOCK_READ_COUNT is used to determine the number of blocks that are read in one batch. For example, if DB_BLOCK_SIZE is equal to 8 KB and DB_FILE_MULTIBLOCK_READ_COUNT is equal to 16, then the amount of I/O data that is read at once is (8 * 16) 128 KB. Ensure that the I/O data size you define does not exceed the MAX_IO_SIZE limit of 1 MB for release 8.1.5. MAX_IO_SIZE is not a configurable parameter. Note that if the values you set for DB_BLOCK_SIZE and DB_FILE_MULTIBLOCK_READ_COUNT exceed 1 MB, you do not receive an error message, but the I/O data size value defaults to 1 MB. See the chapter "Initialization Parameters" in Oracle8i Reference for more information on DB_FILE_MULTIBLOCK_READ_COUNT and MAX_IO_SIZE. 4 Depends on value for DB_BLOCK_SIZE parameter. 5 To use MTS, manually set this parameter to the following value: "(PRO=TCP)".

Initialization Parameters Without Windows NT-Specific Values

Oracle8i Reference describes the default values for many initialization parameters as being operating system-specific. Parameters with Windows NT-operating system specific settings are described in the previous section. However, not all the parameters that Oracle8i Reference describes as having operating system-specific values affect Windows NT. In these cases, Windows NT uses either the default value set in the Oracle8i kernel or does not use the parameter. This table describes these initialization parameters:

Parameter	Description
COMPATIBLE_NO_RECOVERY	Uses default value set in Oracle8i kernel (no Windows NT-specific value).
CPU_COUNT	Oracle8i automatically sets value to number of CPUs available for your Oracle instance.
HI_SHARED_MEMORY_ADDRESS	Not applicable to Windows NT.
SHARED_MEMORY_ADDRESS	Not applicable to Windows NT.
LARGE_POOL_SIZE	Uses maximum value of at least 2 GB.
LOG_BUFFER	Starter database uses value set in Oracle8i kernel (no Windows NT-specific value). The Custom option of the Oracle Database Assistant enables you to customize the value for this parameter.
ORACLE_TRACE_COLLECTION_PATH	Uses default value set in Oracle8i kernel (no Windows NT-specific value)
ORACLE_TRACE_FACILITY_NAME	Uses default value set in Oracle8i kernel (no Windows NT-specific value)
ORACLE_TRACE_FACILITY_PATH	Uses default value set in Oracle8i kernel (no Windows NT-specific value)
SPIN_COUNT	Uses default value set in Oracle8i kernel (no Windows NT-specific value)

Displaying Initialization Parameter Values

Windows NT-specific parameter values can be viewed by using an ASCII editor to open the ORACLE_BASE\ADMIN\DB_NAME\PFILE\INIT.ORA file. To display all parameter values (whether set in the INIT.ORA file or the Oracle8i kernel), enter the following command at the SQL*Plus command prompt:

SQL? SHOW PARAMETER PARAMETER_NAME

where PARAMETER_NAME is the name of a specific initialization parameter.

The value for this parameter, whether defined in the ORACLE_BASE\ADMIN\DB_NAME\PFILE\INIT.ORA file or the Oracle8i kernel, displays on-screen.

Database Initialization Parameters

Check the following initialization parameters when creating a new database. They cannot be modified after you have created the database. See Chapter 8, "Creating a Database" for details on creating a new database, including the part of the procedure when you modify these parameters.

Parameter	Description
CHARACTER SET1	Specifies the database National Language Support (NLS) character set to use. This parameter can be set only when you create the database.
DB_BLOCK_SIZE	Specifies the size in bytes of Oracle database blocks.
DB_NAME	Specifies the name of the database to be created. The database name is a string of eight characters or less. You cannot change the name of a database.

1 Not an initialization parameter, but rather a clause in the CREATE DATABASE statement. See Chapter 8, "Creating a Database" for an example of using this clause.

Calculating Database Limits

Use the size guidelines in the following table to calculate Oracle8i database limits using the equations given in Oracle8i Administrator's Guide.

Type	Size
Maximum block size	16,384 bytes or 16 kilobytes (KB)
Maximum blocks per file	4,194,304 blocks (4 million blocks)
Maximum possible file size with 16 K sized blocks	64 Gigabytes (GB) (4,194,304 * 16,384) = 64 gigabytes (GB)
Maximum number of files per database (depends on block size):
2 K sized blocks	20,000 files
4 K sized blocks	40,000 files
8 K sized blocks	65,536 files
16 K sized blocks	65,536 files
Maximum file size for a FAT file	4 GB
Maximum file size in NTFS	16 Exabytes (EB)
Maximum database size	65,536 * 64 GB equals approximately 4 Petabytes (PB)
Shadow Process Memory:
Release 8.1.3	265 K
Release 8.0.5	233 K
Release 8.0.4	254 K

Calculating Index Size

Use the size guidelines in the following table to calculate the space required by an index using the equations given in Oracle8i Administrator's Guide.

Type	Size
Fixed header size	113 bytes
Variable transaction header	24*INITRANS value for the index
Entry header	5 bytes

---