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nestedmany-to-manyone-to-manystrapi

How to create one-to-many and many-to-many relations in Strapi v.4?

I want to create relations between Post and Tag as follows.

  1. Post has many Tags (one-to-many)
  2. Tags have and belongs to many Posts (many-to-many)

I created collection types for Post and Tag.

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Set them accessible for public user.

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I created 1 post with 3 tags.

Now, when I try to see them at http://localhost:1337/api/posts I don’t see nested elements, i.e. tags… Am I missing anything ?

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And lastly, I was not able to create Many-to-Many relations between Post and Tag with the following error. I understand that Tags field already exists, but I thought this is how supposed to be set.

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Solution

  • I got reply from Strapi forum, so decided to share here.

    https://docs.strapi.io/developer-docs/latest/developer-resources/database-apis-reference/rest/populating-fields.html

    According to the docs above, to pull (in my case) 1st level nested elements I have to add populate[0] parameter like so:

    http://localhost:1337/api/posts?populate[0]=tags

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