Error "1038 Out of sort memory, consider increasing sort buffer size

问题

In symfony2, doctrine2, I have a query which triggers an error :

Error "1038 Out of sort memory, consider increasing server sort buffer size

The query :

$queryBuilder = $this
    ->createQueryBuilder('object')
    ->leftJoin('object.objectCategory', 'c')
    ->leftJoin('object.medias', 'm')
    ->leftJoin('object.recipients', 'r')
    ->leftJoin('object.answers', 'a')
    ->leftJoin('object.tags', 't')
    ->leftJoin('object.user', 'u')
    ->leftJoin('object.votes', 'v')
    ->leftJoin('object.comments', 'comments')
    ->leftJoin('v.user', 'vuser')
    ->addSelect('c, t, v, u')
    ->groupBy('object, c, t, v, u')
    ->where('object.isVisible = :isVisible')
    ->orderBy('object.createdAt', 'DESC')
    ->setParameter('isVisible', true)
    ->addSelect('SUM(v.value) AS HIDDEN vote_value')
    ->orderBy('vote_value', 'DESC')
    ;

If I omit the group by, it runs just fine. If I add select and group by less elements, it runs fine also but then I have more subqueries launched in my twig templates.

How can I either optimize this query to not have the error OR get rid of the error by allocating more memory (ideally just for this query) ?

回答1:

You probably need to increase the buffer size of mysql in the /etc/mysql/my.cnf , set

sort_buffer_size to 256K

来源：https://stackoverflow.com/questions/29575835/error-1038-out-of-sort-memory-consider-increasing-sort-buffer-size