mysql - on 子句 MySQL 中的未知列

Question

我想访问 MySQL 子查询中的一个字段，但我收到了一个未知列 'var_customer_id' in 'on clause' 错误。这是我的代码:

SELECT *,
        CONCAT(customer_phone_1, ', ', customer_phone_2) AS customer_phone,
        CONCAT(customer_fax_1, ', ', customer_fax_2) AS customer_fax,
        CONCAT(customer_email_1, ', ', customer_email_2) AS customer_email,
        tbl_customer.customer_id AS var_customer_id,                
        (
            SELECT
                GROUP_CONCAT(tbl_service.service_name SEPARATOR ', ')
            FROM
                kuesioner_bbia.tbl_customer_service
                INNER JOIN kuesioner_bbia.tbl_service 
                ON (tbl_customer_service.service_id = tbl_service.service_id )
                AND tbl_customer_service.customer_id=var_customer_id                    
            GROUP BY tbl_customer_service.customer_id                   
            )               

        FROM tbl_customer
        ORDER BY customer_id ASC

那么怎么解决呢？对不起我的英语。

Answer 1

错误在这里:

ON (tbl_customer_service.service_id = tbl_service.service_id )
                AND tbl_customer_service.customer_id=var_customer_id   

可以是以下任意一种(注:我把var_customer_id换成了tbl_customer.customer_id):

ON (tbl_customer_service.service_id = tbl_service.service_id )
WHERE tbl_customer_service.customer_id = tbl_customer.customer_id

或(重新定位右括号):

ON (tbl_customer_service.service_id = tbl_service.service_id 
AND tbl_customer_service.customer_id = tbl_customer.customer_id)