MIN returns the smallest value of a column.
MAX returns the biggest value of a column.
-- return the lowest total_price from orders of user with id of 10
SELECT MIN(total_price) FROM orders WHERE user_id = 10;
-- +------+
-- | min |
-- |------|
-- | 1132 |
-- +------+
-- return the highest total_price from the orders of user with id of 10
SELECT MAX(total_price) FROM orders WHERE user_id = 10;
-- +------+
-- | max |
-- |------|
-- | 1998 |
-- +------+
