How special character (Unicode) characters are stored

References to SQL database solutions for saving special characters

The difference between varchar and nvarchar, and text and ntext?

varchar and text cannot be stored "(? ´ 艸 '?)" This string, added in, eventually becomes "(? 艸 ')"

--The following quoted netizens Baidu know reply

varchar (n)
variable-length, non-Unicode character data with a length of n bytes. n must be a numeric value between 1 and 8,000. Storage size is the actual length of bytes of input data, not n bytes. 

nvarchar (n)
a variable-length Unicode character data that contains n characters. The value of n must be between 1 and 4,000. The storage size of bytes is twice times the number of characters entered. 

Two fields have field values, respectively: me and coffee .
The varchar field accounts for 2x2+6=10 bytes of storage, while the nvarchar field accounts for 8x2=16 bytes of storage space. 

If the field value is only English can choose varchar, and the field value exists more double-byte (Chinese, Korean , etc.) characters with nvarchar

above is a summary of the introduction, through the above introduction, you can know. 

varchar (4) You can enter 4 letters or two characters

nvarchar (4) can lose four characters, can also lose 4 letters, but a maximum of four

How special character (Unicode) characters are stored