Overriding order from preparation in relationships

[lcmen]

Hello!
I'm following examples from "Ash Framework" book and I was wondering if it's possible to override sort defined in resource preparations block in the relationship.

Example:

defmodule Tunez.Music.Album do
  preparations do
    prepare build(sort: [year: :asc])
  end
end

defmodule Tunez.Music.Artist do
  relationships do
    has_many :albums, Tunez.Music.Album, sort: [year: :desc]
  end
end

When preloading albums through artist (ar = Tunez.Music.read_artist("43159369-82f2-4b51-a370-9dfb80786cfa", load: :albums):

A following query is used (ORDER BY a0."year", a0."year" DESC):

[debug] QUERY OK source="artists" db=1.2ms idle=1290.6ms
SELECT a0."id", a0."name", a0."created_at", a0."updated_at", a0."biography" FROM "artists" AS a0 WHERE (a0."id"::uuid = $1::uuid) ["43159369-82f2-4b51-a370-9dfb80786cfa"]
↳ anonymous fn/3 in AshPostgres.DataLayer.run_query/2, at: lib/data_layer.ex:785
[debug] QUERY OK source="albums" db=0.9ms idle=1292.7ms
SELECT a0."id", a0."name", a0."year", a0."image_url", a0."artist_id", a0."created_at", a0."updated_at" FROM "albums" AS a0 WHERE (a0."artist_id"::uuid = ANY($1::uuid[])) ORDER BY a0."year", a0."year" DESC [["43159369-82f2-4b51-a370-9dfb80786cfa"]]

Thanks!

[sevenseacat]

Hello! Yes, that preparation should be moved to be a sort on the relationship, and that's a change we'll be making for the next version of the Ash Framework book.

In your example, both sorts are applied - the default sort takes precedence as a global sort and will be applied first, and then the relationship sort will come second.

[lcmen]

Thank you for responding so quickly and for clarification.

I just thought it's possible to override a global sort on relationship (e.g. similarly to what you can achive in Rails with reorder) given that book says:

While a default sort can be undone by applying another sort, you can’t undo a filter that removes records from a query.

PS. Sorry for Rails example, it's just what I do on day-to-day basis.

[sevenseacat]

I thought so too, hence writing that! I've since learned its not the case.

I did some testing with sorts in global preparations, in action preparations, and on relationships - and they get applied in that order, so a global preparation is actually the most important.

I'm revising that little part to remove the preparation, and put the sort on the relationship instead. I'll find somewhere else to introduce preparations!

[lcmen]

Thank you for clarification! I thought the problem was on my side :)

[lcmen]

Added in #1786