Question

我必须创建一个视图来显示数据库中订单的概述。概述不需要订单商品，只需订单ID，订单日期，客户名称，订单总数和订单状态。在数据库中，有2个表包含客户详细信息（一个用于注册用户，一个用于未注册用户），shop_customer和shop_temp_customer。

我需要视图从相关表中提取客户的姓名和姓氏，以便我可以在订单概览页面上显示它。

以下是表结构：

shop_orders：

Column Name             Column Type    Null Default

order_id                int(11)         No  None
order_date              int(255)        No  None
order_customer_id       int(11)         Yes NULL
order_temp_customer_id  int(11)         Yes NULL
order_postage           double(11,2)    No  None
order_discount          double(11,2)    No  None
order_total             double(11,2)    No  None
order_status            tinyint(1)      No  None

shop_customers：

Column Name               Column Type  Null Default

customer_id               int(11)       No  None
customer_title            varchar(255)  No  None
customer_forename         varchar(255)  No  None
customer_surname          varchar(255)  No  None
customer_company          varchar(255)  No  None
customer_contact_number   varchar(255)  No  None
customer_email            varchar(255)  No  None
customer_password         varchar(255)  No  None
customer_reference        varchar(255)  No  None
customer_marketing        tinyint(1)    No  None
customer_active           tinyint(1)    No  None
customer_decomission_date int(11)       No  None

shop_temp_customers：

Column Name                     Column Type    Null Default

temp_customer_id                int(11)         No  None
temp_customer_title             varchar(255)    No  None
temp_customer_forename          varchar(255)    No  None
temp_customer_surname           varchar(255)    No  None
temp_customer_company           varchar(255)    No  None
temp_customer_contact_number    varchar(255)    No  None
temp_customer_email             varchar(255)    No  None
temp_customer_reference         varchar(255)    No  None
temp_customer_decomission_date  int(11)         No  None

以下是我的视图代码，但它没有提取任何数据项：

CREATE VIEW shop_order_view_all_preview AS
SELECT o.order_id, o.order_date, c.customer_forename, c.customer_surname, tc.temp_customer_forename, tc.temp_customer_surname, o.order_total, o.order_status
FROM shop_orders o
RIGHT JOIN shop_customers c
ON c.customer_id = o.order_customer_id
RIGHT JOIN shop_temp_customers tc
ON tc.temp_customer_id = o.order_customer_id

有什么想法吗？

编辑：

以下是表格中的一些数据：

shop_orders：

order_id order_date order_customer_id order_temp_customer_id order_postage order_discount order_total order_status
1        1322697540 2                 NULL                   12.50         0.00           1012.50     0
2        1322697540 NULL              1                      13.00         0.00           1200.00     1

shop_customer：

customer_id customer_title customer_forename customer_surname customer_company customer_telephone customer_email customer_password                 customer_reference customer_marketing customer_active customer_decomission_date
2           Mr             b                 a                d                 044444            a@test.com     098f6bcd4621d373cade4e832627b4f6  Poster / Flyer     1                  1               0

shop_temp_customer：

temp_customer_id temp_customer_title temp_customer_forename temp_customer_surname temp_customer_company temp_customer_contact_number temp_customer_email temp_customer_reference temp_customer_decomission_date
 1               Mr                  e                      asy                   NULL                  04444                        test@test.com       Google                  1322697540

Answer 1

尝试使用左连接而不是右连接，因为包含所有订单的表位于左侧：

CREATE VIEW shop_order_view_all_preview
AS
SELECT
  o.order_id,
  o.order_date,
  c.customer_forename,
  c.customer_surname,
  tc.temp_customer_forename,
  tc.temp_customer_surname,
  o.order_total,
  o.order_status
FROM shop_orders o
  LEFT JOIN shop_customers c ON c.customer_id = o.order_customer_id
  LEFT JOIN shop_temp_customers tc ON tc.temp_customer_id = o.order_customer_id

这可能无法解决问题，但我会先尝试一下。

Answer 2

最后一行的一个小问题：

CREATE VIEW shop_order_view_all_preview AS
SELECT o.order_id, o.order_date, c.customer_forename, c.customer_surname, tc.temp_customer_forename, tc.temp_customer_surname, o.order_total, o.order_status
FROM shop_orders o
LEFT JOIN shop_customers c
ON c.customer_id = o.order_customer_id
LEFT JOIN shop_temp_customers tc
ON tc.temp_customer_id = o.order_temp_customer_id
--                               ^^^^^

- 您将订单表中的永久 customer_id链接到临时客户表，即使订单表上有单独的字段用于临时客户ID。

编辑：将右连接更改为左连接 - 订单表应位于连接的内。

Answer 3

试试这个......

CREATE VIEW shop_order_view_all_preview AS
      SELECT
       shop_orders.order_id, shop_orders.order_date, shop_customers.customer_forename, shop_customers.customer_surname, shop_temp_customers.temp_customer_forename, shop_temp_customers.temp_customer_surname, shop_orders.order_total, shop_orders.order_status
      FROM 
       shop_orders, shop_customers, shop_temp_customers 
      RIGHT JOIN shop_customers 
      ON customer_id = order_customer_id
      AND
      RIGHT JOIN shop_temp_customers
      ON temp_customer_id = order_customer_id

具有右连接的SQL视图

3 个答案: