mysql - 如何使用 sql 查询加入我的发票和发票产品表..？

Question

我有两个表发票和发票产品表，我想根据每个发票 ID 加入我的两个表。

我试过写 sql 查询，但它是错误的。

SELECT invoice.invoice_id, invoice_product.product_name
FROM invoice, invoice_product
WHERE invoice.invoice_id = invoice_product.invoices_id

我想像这样显示我的实际结果。

Invoice_id | Invoice_name | Product_name                | Created Date
========== |============= |=============================|==============
   1       |    Test 1    |   Product1 ,product 2       | 2019-05-02
   2       |    Test 2    |    New Product ,New Product | 2019-05-02

发票表:

invoice_product 表:

Answer 1

避免与您的实际语法结合，这太旧了。 我不建议使用非原子值，但 GROUP_CONCAT 函数正在为您完成这项工作。

SELECT invoice.invoice_id, GROUP_CONCAT(IP.product_name), I.created_at
FROM invoice AS I
JOIN invoice_product AS IP
    ON I.invoice_id = IP.invoices_id
GROUP BY IP.invoices_id