How SQL Server stores special characters, superscripts, subscripts

Test to verify that special symbols can be stored in the database:

Among them, like some ordinary unit symbols such as "°′〃﹩$﹠&￡￥‰%℃¤￠℉" can be normal input no problem, but the extremely number "?" Above it is not possible, input after the display? ；

There are no problems with digital sign entry, including ancient Greek numeric characters and circle characters, such as "Ⅰⅱⅲⅳⅴⅵⅶⅷⅸⅹ①②③④⑤⑥⑦⑧⑨⑩⒈⒉⒊⒋ ⒌⒍⒎⒏⒐⒑⒒⒓⒔⒕⒖⒗⒘⒙⒚⒛⑴⑵⑶⑷⑸⑹⑺⑻⑼⑽⑾⑿⒀⒁⒂⒃⒄⒅⒆⒇㈠㈡㈢㈣㈤㈥㈦㈧㈨㈩ⅰⅱⅲⅳⅴⅵⅶⅷⅸⅹⅺⅻ ";

However, the entry of the digital unit superscript symbol, is not possible, where superscript "O 1 2 3" input directly display numbers, other superscript and subscript "?????? "Display after entry?" Cannot read, and this semicolon number unit "??????????" Display after entry? Cannot read

FIX: When you change the data type to nvarchar, and insert or change data, before the quotation marks + "N", you can insert special symbol characters, for example:

Change: UPDATE a SET a.name2=n ' B? ' From Test a WHERE zid=14

Insert: INSERT INTO Test (name,name2) VALUES (n ' o 1 2 3???????????? ', n '????????? ℅.

Name is a varchar type, name2 is the nvarchar type

How SQL Server stores special characters, superscripts, subscripts