DATABASE ERROR:
SELECT p.id, p.thread_id, p.user_id, p.pubdate, p.editdate, p.edittimes, p.rating, p.attach_count, p.content_html, p.pinned,
                       u.nickname, u.login, u.is_deleted, u.logdate, u.status,
                       up.imageurl, up.signature_html, up.city, up.karma, g.access as group_access, g.is_admin 
                FROM cms_forum_posts p
                
                LEFT JOIN cms_users u ON u.id = p.user_id
                LEFT JOIN cms_user_profiles up ON up.user_id = u.id
                LEFT JOIN cms_user_groups g ON u.group_id = g.id
                WHERE 1=1
                 AND (p.thread_id = '56')

                
                ORDER BY p.pinned DESC, p.pubdate ASC 
LIMIT -15, 15
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '-15, 15' at line 14