Nested aggregates and calculations

I have a calculation that looks like this conceptually:

some_documentation_created (calculation) refers to: 
  count_of_documented_skills (aggregate) filters by:
    status_calculated (calculation) refers to:
      latest_documentation_status (aggregate) sorts by:
        timestamp (calculation)
  all_documentation_approved (calculation) refers to:
    count_of_skills (aggregate)
    count_of_approved_skills (aggregate) filters by:
      status_calculated (calculation) refers to:
        latest_documentation_status (aggregate) sorts by:
          timestamp (calculation)

some_documentation_created (calculation) refers to: 
  count_of_documented_skills (aggregate) filters by:
    status_calculated (calculation) refers to:
      latest_documentation_status (aggregate) sorts by:
        timestamp (calculation)
  all_documentation_approved (calculation) refers to:
    count_of_skills (aggregate)
    count_of_approved_skills (aggregate) filters by:
      status_calculated (calculation) refers to:
        latest_documentation_status (aggregate) sorts by:
          timestamp (calculation)

Can a calculation refer to an aggregate that filters by a calculation (that refers to an aggregate)? If it should be possible, the issue is illustrated here: https://gist.github.com/ahey/2c3fcb0dd215f3a82620563e96344949

Gist

nested_aggregates.ex

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6 Replies

ZachDaniel•2y ago

I believe it should work, yes. This will be pretty hard to debug without a reproduction. Would you be able to reproduce in ash_postgres tests?

Alan HeywoodOP•2y ago

Thanks, good to know it should work. I have submitted a PR that reproduces the issue here: https://github.com/ash-project/ash_postgres/pull/164

GitHub

test: add failing test to demonstrate potential bug by ahey · Pull ...

test complex calculation (AshPostgres.Test.ComplexCalculationsTest) test/complex_calculations_test.exs:5 ** (RuntimeError) Error while building reference: latest_documentation_status code: |> As...

ZachDaniel•2y ago

man, this one was tough Had to put my brain in a blender for this one 😆 Try main of ash_postgres when you get the chance 🙂

Alan HeywoodOP•2y ago

OK this is brilliant, thank you! It gives me confidence that I can continue to build up calculations and aggregates and they will be composable.

ZachDaniel•2y ago

Yep! The only main thing is that aggregates can't point at other aggregates currently but they can point at calculations, which can just be references to aggregates its pretty hacky but doable 🙂

Alan HeywoodOP•2y ago

Ok good to know, and that there's a workaround 😀

Gaming

Programming

Nested aggregates and calculations

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