SQL多对多选择 [英] SQL many to many select

问题描述

category_product
---------------
id_category
id_product

product
---------------
id_product
id_manufacturer

manufacturer
---------------
id_manufacturer
name

当id_category等于某个值时，我将如何创建一个SQL查询，以便从制造商中选择所有名称?

How would I create an SQL query so that it selects all the names from manufacturer when id_category is equal to something?

推荐答案

这是表的直接内部联接:

It's a straightforward inner join of the tables:

SELECT m.name, cp.id_category
FROM manufacturer as m
INNER JOIN product as p
    ON m.id_manufacturer = p.id_manufacturer
INNER JOIN category_product as cp
    ON p.id_product = cp.id_product
WHERE cp.id_category = 'some value'

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