php - 打印每个 products_id 的订单数

Question

有比我更快的解决方案吗？

我有一个包含 orders_id 和 products_id 列的表（无法更改）

现在我想知道有多少订单使用唯一 products_id。

我尝试了以下。但是它在加载太多行（160'000）时崩溃。

    SELECT  DISTINCT `products_id` ,  `products_name` , COUNT(*) as totalorders FROM  `orders_products` ORDER BY  `products_id` ASC 

我也尝试了子查询，但问题与上述相同。

    SELECT (SELECT count(*) FROM orders_products WHERE products_id = op.products_id) AS totalorders, products_id, products_name FROM orders_products op ORDER BY products_id ASC

Answer 1

怎么样：

SELECT `products_id`, `products_name`, COUNT(*) FROM `orders_products` GROUP BY (`products_id`, `products_name`) ORDER BY `products_id`

Answer 2

希望您对 products_id 有一个索引

在这种情况下，我会尝试以下方法：

select products_id, Min(Products_Name), count(*) as TotalOrders from Orders_Products Group by Products_ID Order by Products_ID asc

您可以通过其他几种方式获取 products_name，例如将其包含在您的分组中（还有其他一些含义）。