Sorting not working on user id

[nabtron]

I tried several custom queries to show, they do show but sorting doesn't work.

E.g. i tried:

$value = get_the_author_id($post_id);

(Yes I know I can show author id directly by built-in feature too), however this step is crucial (imho) in what I need to do. I'll be using this to get info from another table related to this user.

If I show any other data like meta data here or post id directly, it works.

Am I doing something wrong? or is it a bug?