MySQL enmu枚举类型能用avg()否求平均值

Functions such as SUM() or AVG() that expect a numeric argument cast the argument to a number if necessary. For ENUM values, the index number is used in the calculation.

->For calculate the average or summation of list of ENUM column values(numbers) then we have to first convert its type to CHARACTER then to INTEGER otherwise that will calculated its result based on its index value.

For example:
SELECT
AVG(CAST(CAST(enum_col AS CHAR) AS UNSIGNED INTEGER)) AS enum_avg
FROM table_name;

I hope the above informations regarding ENUM will give you some brief idea.