#1221 - Incorrect usage of UPDATE and ORDER BY

Question

To bypass a problem I posted in a other thread. I tried an sql statement like this:

UPDATE user u JOIN (SELECT @i := 0) r
SET user_rank_planets = (@i := (@i          


        

Answer 1

The @1000111's answer doesn't work. I don't know the reason but MySQL just ignored the ORDER BY in the subquery and updated with the default order (by the Primary_key). A silly solution is wrapping the subquery inside another subquery to create a temporary table.

UPDATE user u 
INNER JOIN 
(
    SELECT * FROM (
        SELECT *, (@i := (@i + 1)) AS row_number
        FROM user u 
        CROSS JOIN (SELECT @i := 0) r
        WHERE user_active=1
        ORDER BY user_planets DESC
    ) AS t1
) AS t
ON u. = t.
SET u.user_rank_planets = t.row_number