ALTER TABLE `vn`.`starredModule`
	ADD `position` INT NOT NULL AFTER `moduleFk`;

SET @count:=0;
UPDATE `vn`.`starredModule` sm
    JOIN (
        SELECT sm.id, IF(@workerFk = sm.workerFk, @count:=@count+1, @count:=1) AS position, @workerFk:=sm.workerFk
            FROM `vn`.`starredModule` sm ORDER BY workerFk, moduleFk ASC) AS smt ON smt.id = sm.id
    SET sm.position = smt.position;