Character data types that are either fixed-length (nchar) or variable-length (nvarchar) Unicode data and use the UNICODE UCS-2 character set.
When n is not specified in a data definition or variable declaration statement, the default length is 1. When n is not specified with the CAST function, the default length is 30.
Use nchar when the data entries in a column are expected to be consistently close to the same size.
Use nvarchar when the data entries in a column are expected to vary considerably in size.
SET ANSI_PADDING OFF does not apply to nchar or nvarchar. SET ANSI_PADDING is always ON for nchar and nvarchar.