如何在MySQL中找到非ASCII字符？

SELECT column_name FROM table_name WHERE HEX(column_name) REGEXP '^(..)*[8-9A-F][0-9A-F]$';

SELECT column_name FROM table_name WHERE CHAR_LENGTH(column_name) <> LENGTH(column_name);

SELECT column_name FROM table_name WHERE column_name REGEXP '[^\x00-\x7F]';