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preload_in_result(arg, repo, preloads)

Preload the associations in a database result.

It accepts the following types of result:

  • {:ok, struct} where struct is an ecto schema
  • {:error, changeset} where changeset is a changeset

This function is optimized to process the results of operations such as c:Repo.insert/1 and c:Repo.update/1.