DB_UNIQUE_NAME

Property	Description
Parameter type	String
Syntax	DB_UNIQUE_NAME = database_unique_name
Default value	Database instances: the value of DB_NAME Automatic Storage Management instances: +ASM
Modifiable	No
Basic	Yes
Real Application Clusters	Multiple instances must have the same value.

DB_UNIQUE_NAME specifies a globally unique name for the database. Databases with the same DB_NAME within the same DB_DOMAIN (for example, copies of a database created for reporting or a physical standby) must have a unique DB_UNIQUE_NAME. Every database's DB_UNIQUE_NAME must be unique within the enterprise.

The value of DB_UNIQUE_NAME can be up to 30 characters and is case insensitive. The following characters are valid in a database name: alphanumeric characters, underscore (_), number sign (#), and dollar sign ($).

Note:

1. This parameter was introduced in 10g.

2. Query for the current value of the parameter

select name, value, isdefault, isses_modifiable, issys_modifiable,

isinstance_modifiable, isdeprecated, description

from v$parameter

where upper(name) = ‘DB_UNIQUE_NAME’;

NAME	VALUE	IS DEFAULT	ISSES_ MODIFIABLE	ISSYS_ MODIFIABLE	ISINSTANCE_ MODIFIABLE	IS DEPRECATED	DESCRIPTION
db_unique_name	mydb	TRUE	FALSE	FALSE	FALSE	FALSE	Database Unique Name

Oracle initializatoin parameters

DB_ULTRA_SAFE

Property	Description
Parameter type	String
Syntax	DB_ULTRA_SAFE = { OFF | DATA_ONLY | DATA_AND_INDEX }
Default value	OFF
Modifiable	No
Basic	No

DB_ULTRA_SAFE sets the default values for other parameters that control protection levels.

Values:

· OFF

When any of DB_BLOCK_CHECKING, DB_BLOCK_CHECKSUM, or DB_LOST_WRITE_PROTECT are explicitly set, no changes are made.

· DATA_ONLY

o DB_BLOCK_CHECKING will be set to MEDIUM.

o DB_LOST_WRITE_PROTECT will be set to TYPICAL.

o DB_BLOCK_CHECKSUM will be set to FULL.

· DATA_AND_INDEX

o DB_BLOCK_CHECKING will be set to FULL.

o DB_LOST_WRITE_PROTECT will be set to TYPICAL.

o DB_BLOCK_CHECKSUM will be set to FULL.

Note:

1. This parameter was introduced in 11g.

2. Query for the current value of the parameter

select name, value, isdefault, isses_modifiable, issys_modifiable,

isinstance_modifiable, isdeprecated, description

from v$parameter

where upper(name) = ‘DB_ULTRA_SAFE’;

Oracle initializatoin parameters

DB_SECUREFILE

Property	Description
Parameter type	String
Syntax	DB_SECUREFILE = { NEVER | PERMITTED | ALWAYS | IGNORE }
Default value	PERMITTED
Modifiable	ALTER SESSION, ALTER SYSTEM
Basic	No

DB_SECUREFILE specifies whether or not to treat LOB files as SecureFiles.

Values:

· NEVER

Any LOBs that are specified as SecureFiles are created as BasicFile LOBs. All SecureFile-specific storage options and features (for example, compress, encrypt, deduplicate) will cause an exception. The BasicFile LOB defaults will be used for storage options not specified.

· PERMITTED

LOBs are allowed to be created as SecureFiles.

· ALWAYS

All LOBs created in the system are created as SecureFile LOBs. If the LOB is not created in an Automatic Segment Space Managed tablespace, then an error will occur. Any BasicFile LOB storage options are ignored. The SecureFile defaults will be used for all storage options not specified.

· IGNORE

The SECUREFILE keyword and all SecureFile options are ignored.

If the COMPATIBLE initialization parameter is not set to 11.1 or higher, then LOBs are not treated as SecureFiles.

If there is a LOB column with two partitions (one that has a tablespace for which ASSM is enabled and one that has a tablespace for which ASSM is not enabled), then LOBs in the partition with the ASSM-enabled tablespace will be treated as SecureFiles and LOBs in the other partition will be treated as BasicFile LOBs.

Note:

1. This parameter was introduced in 11g.

2. Query for the current value of the parameter

select name, value, isdefault, isses_modifiable, issys_modifiable,

isinstance_modifiable, isdeprecated, description

from v$parameter

where upper(name) = ‘DB_SECUREFILE’;

Oracle initializatoin parameters

DB_RECYCLE_CACHE_SIZE

Property	Description
Parameter type	Big integer
Syntax	DB_RECYCLE_CACHE_SIZE = integer [K | M | G]
Default value	0 (DB_RECYCLE_CACHE_SIZE is not configured by default)
Modifiable	ALTER SYSTEM
Range of values	Minimum: 0 (values greater than zero are automatically modified to be either the user-specified size rounded up to the granule size or 4 MB * number of CPUs, whichever is greater) Maximum: operating system-dependent
Basic	No

DB_RECYCLE_CACHE_SIZE specifies the size of the RECYCLE buffer pool. The size of the buffers in the RECYCLE pool is the primary block size (the block size defined by the DB_BLOCK_SIZE initialization parameter).

Note:

1. This parameter was introduced in Oracle9i.

2. Query for the current value of the parameter

select name, value, isdefault, isses_modifiable, issys_modifiable,

isinstance_modifiable, isdeprecated, description

from v$parameter where upper(name) = ‘DB_RECYCLE_CACHE_SIZE’;

NAME	VALUE	IS DEFAULT	ISSES_ MODIFIABLE	ISSYS_ MODIFIABLE	ISINSTANCE_ MODIFIABLE	IS DEPRECATED	DESCRIPTION
db_recycle_cache_size	0	TRUE	FALSE	IMMEDIATE	TRUE	FALSE	Size of RECYCLE buffer pool for standard block size buffers

Oracle initializatoin parameters

DB_RECOVERY_FILE_DEST_SIZE

Property	Description
Parameter type	Big integer
Syntax	DB_RECOVERY_FILE_DEST_SIZE = integer [K | M | G]
Default value	There is no default value.
Modifiable	ALTER SYSTEM ... SID='*'
Basic	Yes
Real Application Clusters	You must set this parameter for every instance, and multiple instances must have the same value.

DB_RECOVERY_FILE_DEST_SIZE specifies (in bytes) the hard limit on the total space to be used by target database recovery files created in the flash recovery area.
Note that neither block 0 nor the OS block header of each Oracle file is included in this size. Allow an extra 10% for this data when computing the actual disk usage required for the flash recovery area.
Note:

1. This parameter was introduced in 10g.

2. Query for the current value of the parameter

select name, value, isdefault, isses_modifiable, issys_modifiable,

isinstance_modifiable, isdeprecated, description

from v$parameter

where upper(name) = ‘DB_RECOVERY_FILE_DEST_SIZE’;

NAME	VALUE	IS DEFAULT	ISSES_ MODIFIABLE	ISSYS_ MODIFIABLE	ISINSTANCE_ MODIFIABLE	IS DEPRECATED	DESCRIPTION
db_recovery_file_dest_size	0	TRUE	FALSE	IMMEDIATE	FALSE	FALSE	database recovery files size limit

Oracle initializatoin parameters

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