Mysql加入请求

Question

我需要获取重复数据的空字段

例如一个客户可以有两个或两个以上的联系人，那么查询返回(只是简写qyery resul):

CUSTOMER_NAME| CONTACT_PERSON|等..

  dell         |    Ighor      |etc..
  dell         |    Dima       |etc..

但我需要:CUSTOMER_NAME| CONTACT_PERSON|等...

             dell         |    Ighor      |etc..
             NULL         |    Dima       |etc..


SELECT
             `contact`.*,
                 `branch_has_equipment`.*,
             `branch_has_contact`.*,
                         `equipment`.*,
                         `customer_has_branch`.*,
                         `branch`.*,
                         `customer`.*,
              `ip`.*

                 FROM `customer`
                 INNER JOIN `customer_has_branch`
                         ON `customer`.`customer_id` = `customer_has_branch`.`customer_id`
                 INNER JOIN `branch`
                         ON `customer_has_branch`.`branch_id` = `branch`.`branch_id`
                 INNER JOIN `branch_has_equipment`
                         ON `branch`.`branch_id` = `branch_has_equipment`.`branch_id`
                 INNER JOIN `equipment`
                         ON `branch_has_equipment`.`equipment_id` = `equipment`.`equipment_id`
                 INNER JOIN `branch_has_contact`
                         ON `branch`.`branch_id` = `branch_has_contact`.`branch_id`
                 INNER JOIN `contact`
                         ON `branch_has_contact`.`contact_id` = `contact`.`contact_id`

                INNER JOIN `equipment_has_ip`
                        ON `equipment`.`equipment_id` = `equipment_has_ip`.`equipment_id`
                INNER JOIN `ip`
                        ON `equipment_has_ip`.`equipment_id` = `ip`.`ip_id`  

                 WHERE `customer`.`inservice` = 'Yes'
                         ORDER BY `customer`.`customer_name`

另外还有表格^

客户

客户编号顾客姓名在职服务类型评论

分支机构

分支编号城市地址

设备

设备编号品牌模型连接参数连接类型序列号ID释放

联系方式

联系人编号姓名姓phone_mobilephone_workphone_other位置

customer_has_branch_id客户ID分支编号

Answer 1

因为我不知道这些表中的任何一个是如何相互关联的，我唯一的答案是使用 OUTER JOIN，这将保留 NULL 结果。