mysql n:m关系:查找具有几个特定关系的行 [英] mysql n:m relationship: Find rows with several specific relations

问题描述

我有两个SQL表，产品"和标签".它们具有n:m关系，使用第三个表"product_tags".

I have two SQL Tables, 'products' and 'tags'. They have an n:m relationship, using a third table 'product_tags'.

我想使用查询来查找具有多个特定标签的每个产品.例如，找到与标签1、23和54相关的所有产品.

I want to use a query to find every product that has a number of specific tags. For example, find every products that has a relation to the tags 1, 23 and 54.

是否有一种方法可以只执行一个查询?

Is there a way to do this with just one query?

推荐答案

您可以使用此解决方案.这将获取所有包含 ALL 关键字1、23和54的产品:

You can use this solution. This gets all products that contain ALL keywords 1, 23, and 54:

SELECT a.*
FROM products a
INNER JOIN product_tags b ON a.product_id = b.product_id
WHERE b.tag_id IN (1,23,54)
GROUP BY a.product_id
HAVING COUNT(1) = 3

3是WHERE IN列表中项目的数量，因此您可以根据要检查的标签数量进行相应调整.

Where 3 is the number of items in your WHERE IN list, so you can adjust accordingly based on the amount of tags you want to check on.

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