mysql - 从两个表中获取信息

Question

我有两个包含以下信息的表

models

id      manufactor 
1       Mercedes
2       Ford
3       Volvo

orders
car_id customer_id
1      4
1      22
2      54
1      95

我想要一个查询，该查询将给出一行制造商名称以及每种型号的销售量。

这是我尝试过的:

SELECT
  m.make
FROM models m
LEFT JOIN(
    SELECT COUNT(*)FROM orders
) o on o.car_id = m.id

Answer 1

试试这个:

SELECT m.manufactor, COUNT(o.car_id)
FROM models m
LEFT JOIN orders o ON m.id = o.car_id
GROUP BY o.car_id