V$NLS_VALID_VALUES lists all valid values for NLS parameters.
| Column | Datatype | Description | 
|---|---|---|
| PARAMETER | VARCHAR2(64) | Parameter name ( LANGUAGE|SORT|TERRITORY|CHARACTERSET) | 
| VALUE | VARCHAR2(64) | NLS parameter value | 
| ISDEPRECATED | VARCHAR2(5) | Indicates whether the parameter has been deprecated ( TRUE) or not (FALSE) |