Currently the xxx-users loader is not using Dataloader , because the limit and offset in the query will affect the whole result set and not each association, this can be solved by a "Top N per Group" case, but the syntax is ugly ...

reference links:

https://elixirforum.com/t/preloading-top-comments-for-posts-in-ecto/1052/8
elixir-ecto/ecto#2281
https://spin.atomicobject.com/2016/03/12/select-top-n-per-group-postgresql/
https://stackoverflow.com/questions/40529699/how-to-select-id-with-max-date-group-by-category-in-ecto-query-with-phoenix
http://www.achraf-sallemi.com/select-top-n-per-group-in-postgresql/