$result = db_query("SELECT id, exp, name FROM {resubmt_users_skills} LEFT JOIN {resubmt_skill_ids} USING (id) WHERE resubmt_users_skills.uid = :uid", array(':uid' => $user.uid))->fetchAssoc();
That should work just fine and doesn't require the overhead of dynamic queries. I'm not too sure about the fetchAssoc() because I don't bother with array results any more.