如何联接三个mysql表并为给定属性（customerNumber）选择行

Question

我正在尝试编写一个实现以下目的的MySQL查询：

基于所选的customerNumber，应显示所有

ERD如下所示：

对于每个选定的客户编号，我只需要订单，订单明细和产品表中的数据。

Answer 1

您可以尝试执行此操作并更改使它生效所需的内容。

因此，每个*必须替换为要显示的表的列的列表：

SELECT 
    C.customerNumber ,  -- the customer id
    O.*,                -- replace by O.column_name1, O.column_name2, ...
    OD.*,               -- replace by OD.column_name1, OD.column_name2, ...
    P.*                 -- replace by P.column_name1, P.column_name2, ...
FROM customers as C
-- If you only want customer with at least ONE orders, change LEFT JOIN by INNER JOIN
LEFT JOIN orders as O on O.customerNumber = C.customerNumber
-- I suppose orderLineNumber is the same than orderNumber in table orders?
LEFT JOIN orderdetails as OD on OD.orderLineNumber = O.orderNumber 
LEFT JOIN products as P on P.productCode = OD.productCode
-- The result will be order by customerNumber, of for each customerNumber by orderDate
ORDER BY C.customerNumber, O.orderDate

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