Used to determine whether the parameter is in National charset.
property National: Boolean default False;
Use the National property to determine or set whether a parameter is in National character set. When National is True, the parameter is in National character set, otherwise the parameter is in default characterset.
The parameter datatype must be one of the following: ftString, ftFixedChar, ftWideString, ftMemo or ftFixedWideChar.
Supported with Oracle 8 and higher, not supported in Direct mode.