在子查询中添加条件，如下所示

Question

子查询返回超过1行？闷闷不乐？

＆＃13;

SELECT `t_files`.*, `t_users`.`username`, 
(SELECT CONCAT(b.first_name, " ", b.last_name)
	FROM t_files AS a
	JOIN t_users as b 
          ON b.id = a.user_id 
) as upload_by 
FROM `t_files` 
LEFT JOIN `t_files_permission` 
   ON `t_files_permission`.`id_files` = `t_files`.`file_id` 
LEFT JOIN `t_users` 
   ON `t_users`.`id` = `t_files_permission`.`id_users`
WHERE `t_files`.`company_id` = '1' 
  AND `t_files_permission`.`id_users` = '59' 
  AND `is_deleted` =0

＆＃13;

Answer 1

在子查询中添加条件，如下所示

SELECT t_files。*，t_users。username，（SELECT CONCAT（b.first_name，＆＃34;＆＃34;，b.last_name） FROM t_files AS a JOIN t_users AS b ON b.id = a.user_id

在哪里a.id_users` =＆＃39; 59＆＃39;

）作为upload_by 来自t_files LEFT JOIN t_files_permission点击t_files_permission。id_files = t_files。file_id LEFT JOIN t_users点击t_users。id = t_files_permission。id_users 在t_files。company_id =＆＃39; 1＆＃39;和t_files_permission。id_users =＆＃39; 59＆＃39; AND is_deleted = 0

Answer 2

试试这种方式

SELECT `t_files`.*, `t_users`.`username`, 
(select CONCAT(b.first_name, " ", b.last_name)
    from t_files as a
     join t_users as b on b.id = a.user_id 
     where t.files.id=a.id) as upload_by 
FROM `t_files` as 
LEFT JOIN `t_files_permission` ON `t_files_permission`.`id_files` = `t_files`.`file_id` 
LEFT JOIN `t_users` ON `t_users`.`id` = `t_files_permission`.`id_users`
WHERE `t_files`.`company_id` = '1' AND `t_files_permission`.`id_users` = '59' AND `is_deleted` =0

我认为你不需要子查询。您可以使用联接来解决问题。

子查询返回超过1行？

2 个答案:

在子查询中添加条件，如下所示