B
Initialization Parameters

Oracle8 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 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 INITSID.ORA, where SID is the name of the database instance. For example, the initialization parameter file for the first starter database on your computer is named INITORCL.ORA. For each subsequent starter database installed on the same computer, the last letter of ORCL is replaced by a number and automatically incremented (that is for an initialization parameter file for a second starter database, the SID is ORC1, for a third starter database, the SID is ORC2, and so on.

A single instance might also have several initialization parameter files, each having some differences that affect system performance.

Additional Information:

See Chapter 1, "Initialization Parameters" in Oracle8 Reference for a complete list and descriptions of all initialization parameters.

Location

By default, Oracle8 Enterprise Edition uses the initialization parameter files located in ORACLE_HOME\DATABASE, unless you specify a different initialization file with the PFILE option at database startup.

Editing

To customize Oracle8 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 INITORCL.80 is located in the ORACLE_HOME\DATABASE directory. If you want to use this file as part of database creation:

Rename the file INITSID.ORA where SID is the system identifier of the database instance you want to create.

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 INITSID.ORA used by the starter database is also located in ORACLE_HOME\DATABASE. You can use either INITORCL.80 or INITSID.ORA as a model 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

Oracle8 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 Oracle8 Enterprise Edition for Windows NT.

Initialization Parameter Name Default Value Range of Values

AUDIT_TRAIL

TRUE

NONE (FALSE),
DB (TRUE), OS

BACKGROUND_DUMP_ DEST

%RDBMSnn%\TRACE\

Any valid directory

COMPATIBLE

8.0.0.0.0

Default release to current release

COMMIT_POINT_ STRENGTH

1

0 - 255

CONTROL_FILES

%ORACLE_HOME%\DATABASE\ CTL1%ORACLE_SID%.ORA

Any valid path and filename

DB_BLOCK_BUFFERS

200

200 to 3200

DB_BLOCK_SIZE

2048

512 - 16384

DB_FILES

1022

0 - 1022

DB_FILE_MULTIBLOCK_ READ_ COUNT¹

8

1 - 31²

DB_FILE_SIMULTANEOUS_ WRITES

4

1 - 24

DB_NAME

ORACLE

Any valid database name limited to a maximum of eight characters.

DISTRIBUTED_TRANSACTIONS

25 * TRANSACTIONS

0 - TRANSACTIONS

DML_LOCKS

4 * transactions

20 to unlimited

LOG_ARCHIVE_BUFFER_ SIZE

127

1 - 127

LOG_ARCHIVE_BUFFERS

4

1 - 8

LOG_ARCHIVE_DEST

%RDBMSnn%\

Any valid directory

LOG_ARCHIVE_FORMAT
%%ORACLE_SID%%%S.%T
A valid filename format

LOG_ARCHIVE_START

None

TRUE or FALSE

LOG_CHECKPOINT_ INTERVAL

8000

2 - Unlimited

LOG_FILES

255

2 - 255

LOG_SMALL_ENTRY_MAX_ SIZE

800

0 - Unlimited

MAX_DUMP_FILE_SIZE

10240

0 to 4,000,000

MTS_LISTENER_ADDRESS³

"(ADDRESS=(PROTOCOL=tcp)(PORT=1521)(HOST=IP Address))"

User specific

MTS_MAX_DISPATCHERS

3

User specific

MTS_MAX_SERVERS

3

User specific

MTS_SERVERS

3

User specific

MTS_SERVICE

SID

SID

NLS_LANGUAGE

AMERICAN

Any valid language

NLS_SORT

(Language dependent)

(Language dependent)

NLS_TERRITORY

AMERICA

Any valid territory

OPEN_CURSORS

50

1 - Unlimited

OS_AUTHENT_PREFIX

OPS$

Any character string

PROCESSES

25

3 - Unlimited

REMOTE_LOGIN_ PASSWORDFILE

SHARED

SHARED, EXCLUSIVE, NONE

SNAPSHOT_REFRESH_PROCESSES

0

0 to 10

SEQUENCE_CACHE_ENTRIES

10

10 to 32000

SHARED_POOL_SIZE

6,500,000

300 KB - Unlimited

SORT_AREA_SIZE

65536

0 - Unlimited

SORT_READ_FAC

20

0 - Unlimited

SORT_SPACEMAP_SIZES

512

0 - Unlimited

TEXT_ENABLE

TRUE

TRUE or FALSE

TEMPORARY_TABLE_ LOCKS

SESSIONS

0 - Unlimited

TIMED_STATISTICS

None

TRUE or FALSE

TRANSACTIONS_PER_ ROLLBACK_ SEGMENT

30

1 - 255

USER_DUMP_DEST

%RDBMSnn%\TRACE

Any valid directory

¹ MAX_IO_SIZE is not an initialization parameter. It is used to calculate the maximum size of input/output (I/O) data. For example, to achieve an I/O data size of 128 KB:
For a given DB_BLOCK_SIZE (for example, 8 KB) set DB_FILE_MULTIBLOCK_READ_COUNT to 16. Multiply both values (8 * 16) to achieve a user-defined I/O data size of 128 KB. Note that the value for DB_BLOCK_SIZE is set in the INITSID.ORA file. Ensure that the user-defined I/O data size does not exceed the MAX_IO_SIZE limit of 1 MB for release 8.0.4. However, 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.
² Depends on value for DB_BLOCK_SIZE parameter.
³ The parameters prefixed with MTS are for enabling your database to support a multi-threaded server configuration. See the section "The Multithreaded Server" in Chapter 7, "Process Structure" in Oracle8 Server Concepts for specific information on this feature.

Initialization Parameter Name	Default Value	Range of Values
AUDIT_TRAIL	TRUE	NONE (FALSE), DB (TRUE), OS
BACKGROUND_DUMP_ DEST	%RDBMSnn%\TRACE\	Any valid directory
COMPATIBLE	8.0.0.0.0	Default release to current release
COMMIT_POINT_ STRENGTH	1	0 - 255
CONTROL_FILES	%ORACLE_HOME%\DATABASE\ CTL1%ORACLE_SID%.ORA	Any valid path and filename
DB_BLOCK_BUFFERS	200	200 to 3200
DB_BLOCK_SIZE	2048	512 - 16384
DB_FILES	1022	0 - 1022
DB_FILE_MULTIBLOCK_ READ_ COUNT¹	8	1 - 31²
DB_FILE_SIMULTANEOUS_ WRITES	4	1 - 24
DB_NAME	ORACLE	Any valid database name limited to a maximum of eight characters.
DISTRIBUTED_TRANSACTIONS	25 * TRANSACTIONS	0 - TRANSACTIONS
DML_LOCKS	4 * transactions	20 to unlimited
LOG_ARCHIVE_BUFFER_ SIZE	127	1 - 127
LOG_ARCHIVE_BUFFERS	4	1 - 8
LOG_ARCHIVE_DEST	%RDBMSnn%\	Any valid directory
LOG_ARCHIVE_FORMAT	%%ORACLE_SID%%%S.%T	A valid filename format
LOG_ARCHIVE_START	None	TRUE or FALSE
LOG_CHECKPOINT_ INTERVAL	8000	2 - Unlimited
LOG_FILES	255	2 - 255
LOG_SMALL_ENTRY_MAX_ SIZE	800	0 - Unlimited
MAX_DUMP_FILE_SIZE	10240	0 to 4,000,000
MTS_LISTENER_ADDRESS³	"(ADDRESS=(PROTOCOL=tcp)(PORT=1521)(HOST=IP Address))"	User specific
MTS_MAX_DISPATCHERS	3	User specific
MTS_MAX_SERVERS	3	User specific
MTS_SERVERS	3	User specific
MTS_SERVICE	SID	SID
NLS_LANGUAGE	AMERICAN	Any valid language
NLS_SORT	(Language dependent)	(Language dependent)
NLS_TERRITORY	AMERICA	Any valid territory
OPEN_CURSORS	50	1 - Unlimited
OS_AUTHENT_PREFIX	OPS$	Any character string
PROCESSES	25	3 - Unlimited
REMOTE_LOGIN_ PASSWORDFILE	SHARED	SHARED, EXCLUSIVE, NONE
SNAPSHOT_REFRESH_PROCESSES	0	0 to 10
SEQUENCE_CACHE_ENTRIES	10	10 to 32000
SHARED_POOL_SIZE	6,500,000	300 KB - Unlimited
SORT_AREA_SIZE	65536	0 - Unlimited
SORT_READ_FAC	20	0 - Unlimited
SORT_SPACEMAP_SIZES	512	0 - Unlimited
TEXT_ENABLE	TRUE	TRUE or FALSE
TEMPORARY_TABLE_ LOCKS	SESSIONS	0 - Unlimited
TIMED_STATISTICS	None	TRUE or FALSE
TRANSACTIONS_PER_ ROLLBACK_ SEGMENT	30	1 - 255
USER_DUMP_DEST	%RDBMSnn%\TRACE	Any valid directory

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 9, "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 9, "Creating a Database" for an example of using this clause.

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.

B Initialization Parameters