What is the sorting rule of utf8mb4 in MySQL?

In MySQL, the UTF8MB4 collation is defined based on the Unicode character set. Unicode determines the sorting order for each character based on its Unicode code point, placing it accordingly in the sorting. The UTF8MB4 character set supports all characters in the Unicode character set, including emoji and some rare characters.

The sorting rules for the UTF8MB4 character set are determined based on a sorting algorithm in Unicode, considering factors such as accents, uppercase and lowercase letters, and diacritical marks. Specific sorting rules can be found in the official MySQL documentation at the following link: https://dev.mysql.com/doc/refman/8.0/en/charset-unicode-sets.html.