SQL JOIN使用映射表 [英] SQL JOIN using a mapping table

问题描述

我有三个表:

COLLECTION 
PERSON 
PERSON_COLLECTION

其中PERSON_COLLECTION是映射表id|person_id|collection_id

我现在要选择集合中的所有条目，并按person.name对其进行排序.

I now want to select all entries in collection and order them by person.name.

我是否必须先将单独的表与映射表联接，然后再对结果进行联接?

Do I have to join the separate tables with the mapping table first and then do a join again on the results?

推荐答案

SELECT
    c.*,
    p.Name
FROM
    Collection c
    JOIN Person_Collection pc ON pc.collection_id = c.id
    JOIN Person p ON p.id = pc.person_id
ORDER BY p.Name

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