JOIN和GROUP_CONCAT

Question

努力让这个查询工作：

$query_search = "SELECT questionnaires_index.id, questionnaires_index.ea_num, questionnaires_index.address, questionnaires_index.status, questionnaires_index.json_stored users.username FROM questionnaires_index INNER JOIN users ON questionnaires_index.interviewer_id = users.id WHERE questionnaires_index.interviewer_id IN (SELECT GROUP_CONCAT(id) FROM users WHERE supervisor = (SELECT id FROM users WHERE username = '".$username."'))"; 

收到此错误：

Error in query: . 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 '.username FROM questionnaires_index INNER JOIN users ON users.id = questionnaire' at line 1

查询是工作，直到我说的users.username到结果与设定JOIN语句。请任何帮助。

Answer 1

你已经错过了一个逗号

$ query_search =“SELECT questionnaires_index.id，questionnaires_index.ea_num，questionnaires_index.address，questionnaires_index.status，questionnaires_index.json_stored，users.username FROM questionnaires_index INNER JOIN用户ON questionnaires_index.interviewer_id = users.id WHERE questionnaires_index.interviewer_id IN（SELECT GROUP_CONCAT（id）FROM users WHERE supervisor =（SELECT id FROM users WHERE username ='“。$ username。”'））“;

Answer 2

您似乎忘了在questionnaires_index.json_stored和users.username之间输入逗号。

$query_search = "SELECT questionnaires_index.id, questionnaires_index.ea_num, questionnaires_index.address, questionnaires_index.status, questionnaires_index.json_stored ,users.username FROM questionnaires_index INNER JOIN users ON questionnaires_index.interviewer_id = users.id WHERE questionnaires_index.interviewer_id IN (SELECT GROUP_CONCAT(id) FROM users WHERE supervisor = (SELECT id FROM users WHERE username = '".$username."'))