In the case of a graphic strings, two bytes constitute a character and you use the number of double bytes to represent the length of the string.
对于图形字符串,两个字节组成一个字符,使用双字节数来表示字符串的长度。
2
Since a graphiccharacter is always 2 bytes long, the maximum graphic length that can be indexed is 510 graphic characters, and the column can be defined as VARGRAPHIC (510).