//for listing 
SELECT a.id,a.title,a.create_time,a.edit_time,a.publish_time,a.status,a.index_photo,g.id as gid,g.name as gname,
c.id as cid, c.name as cname,au.id as auid,au.name as auname,u.id as pid,u.name as pname 
FROM (((article AS a LEFT JOIN article_group AS g ON a.article_group_id = g.id ) 
LEFT JOIN category AS c ON g.category_id = c.id) 
LEFT JOIN user as u ON a.poster_id=u.id) 
LEFT JOIN author as au ON a.author_id=au.id 

//for single get
SELECT a.id,a.issue_no,a.title,a.content,a.index_photo,a.remark,a.create_time,a.edit_time,a.publish_time,a.status,
a.edit_count,a.view_count,g.id as gid,g.name as gname,c.id as cid, c.name as cname,
au.id as auid,au.name as auname,u.id as pid,u.name as pname 
FROM (((article AS a LEFT JOIN article_group AS g ON a.article_group_id = g.id ) 
LEFT JOIN category AS c ON g.category_id = c.id) 
LEFT JOIN user as u ON a.poster_id=u.id) 
LEFT JOIN author as au ON a.author_id=au.id