Mysql子查询优化-如何减少/删除子查询

Question

经过多次处理后，我想知道是否可以进一步优化该查询？任何见解都将不胜感激。除了必须使用一堆不理想的子查询之外，我还必须使用其中一个子查询两次，因为“标签”引用不能在 where 子句中使用......(还没有弄清楚如何将其重写为连接来解决该问题)

SELECT `t1`.*, 
(SELECT GROUP_CONCAT(tag_id) FROM media_tag WHERE media_id=t1.id GROUP BY media_id ) as tags, 
(SELECT GROUP_CONCAT(award_id) FROM media_award WHERE media_id=t1.id GROUP BY media_id ) as awards, 
(SELECT GROUP_CONCAT(client_id) FROM media_client WHERE media_id=t1.id GROUP BY media_id ) as clients, 
(SELECT GROUP_CONCAT(collaborator_id) FROM media_collaborator t2 LEFT JOIN collaborator t3 ON t2.collaborator_id=t3.id WHERE media_id=t1.id AND t3.collaborator_type_id='1' GROUP BY media_id ) as agencies, 
(SELECT GROUP_CONCAT(collaborator_id) FROM media_collaborator t2 LEFT JOIN collaborator t3 ON t2.collaborator_id=t3.id WHERE media_id=t1.id AND t3.collaborator_type_id<>'1' GROUP BY media_id ) as collaborators, 
`t2`.`idx`, `t2`.`type` 
FROM (`media` t1) 
LEFT JOIN `sort` t2 ON `t1`.`id`=`t2`.`id` AND t2.type="media" 
WHERE 
    FIND_IN_SET('1',(SELECT GROUP_CONCAT(tag_id) FROM media_tag WHERE media_id=t1.id GROUP BY media_id )) 
    AND IF(t2.tag_id IS NOT NULL,t2.tag_id='1',1) 
GROUP BY `t1`.`id` 
ORDER BY `t1`.`date_mod` DESC, `title` ASC, `t2`.`idx` ASC, `date_mod` DESC, `title` ASC 

Answer 1

您应该尝试最小化每行的选择语句，您可以连接这些行并按一些标识符进行分组，如果您可以发布您的表结构并告诉我们您想从它们那里得到什么信息，那就更好了...