NLS_LENGTH_SEMANTICS

Property	Description
Parameter type	String
Syntax	NLS_LENGTH_SEMANTICS = string Example: NLS_LENGTH_SEMANTICS = 'CHAR'
Default value	BYTE
Modifiable	ALTER SESSION
Range of values	BYTE | CHAR

NLS_LENGTH_SEMANTICS enables you to create CHAR and VARCHAR2 columns using either byte or character length semantics. Existing columns are not affected.

NCHAR, NVARCHAR2, CLOB, and NCLOB columns are always character-based. You may be required to use byte semantics in order to maintain compatibility with existing applications.

NLS_LENGTH_SEMANTICS does not apply to tables in the SYS schema.

Note:

1. 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) = ‘NLS_LENGTH_SEMANTICS’;

NAME	VALUE	IS DEFAULT	ISSES_ MODIFIABLE	ISSYS_ MODIFIABLE	ISINSTANCE_ MODIFIABLE	IS DEPRECATED	DESCRIPTION
nls_length_semantics	BYTE	TRUE	TRUE	IMMEDIATE	TRUE	FALSE	create columns using byte or char semantics by default

Oracle initializatoin parameters