WITH t1 AS ( SELECT c.content_id, c.fans_id, c.read_num, c.show_num, b.author_id FROM c LEFT JOIN b ON c.content_id = b.content_id ), t2 AS ( SELECT t1.author_id, t1.fans_id, t1.content_id, t1.read_num, t1.show_num, a.create_date FROM t1 LEFT JOIN a ON (t1.author_id,t1.fans_id) = (a.author_id,a.fans...