MySQL: How to calculate a place in a rating? Where is the mistake?

Question

MySQL

SET @rank=0;
SELECT @rank:[email protected]+1 AS rank, p.user_id, SUM(ch.integer) as sum
FROM profile p
LEFT JOIN chronometry ch ON ch.user_id = p.user_id
GROUP BY p.user_id
ORDER BY sum DESC;

It turns out wrong . I

suspect that numbering and sorting occur in different realities ))

Answer 1

SET @rank=0;
SELECT @rank:[email protected]+1 AS rank, s.*
FROM (
        SELECT p.user_id, SUM(ch.integer) as sum
        FROM profile p
        LEFT JOIN chronometry ch ON ch.user_id = p.user_id
        GROUP BY p.user_id
        ORDER BY sum DESC
    ) s