Ash SQL Load + Sort + Page Bug

Problem Overview

This repository reproduces a bug in Ash Framework / AshSQL.

Issue: Query fails when combining:

• load (aggregate)
• sort (by calculation using has_one relationship)
• page

The bug only occurs when all three are present together.

Resource Setup

# Chat has a has_one relationship with sorting
has_one :last_message, MyDomain.Message do
  from_many? true
  sort sent_at: :desc
end

# Calculation using the has_one relationship
calculate :last_message_sent_at, :utc_datetime, expr(last_message.sent_at)

# Aggregate
count :message_count, :messages

Reproducing the Issue

Failing Case

# load + sort + page = FAILURE
Chat
|> Ash.Query.for_read(:read)
|> Ash.Query.load([:message_count])
|> Ash.Query.sort(last_message_sent_at: :desc)
|> Ash.Query.page(limit: 10)
|> Ash.read!()

Working Cases

# load + sort (no page) = SUCCESS
Chat
|> Ash.Query.for_read(:read)
|> Ash.Query.load([:message_count])
|> Ash.Query.sort(last_message_sent_at: :desc)
|> Ash.read!()

# load + page (no sort) = SUCCESS
Chat
|> Ash.Query.for_read(:read)
|> Ash.Query.load([:message_count])
|> Ash.Query.page(limit: 10)
|> Ash.read!()

# sort + page (no load) = SUCCESS
Chat
|> Ash.Query.for_read(:read)
|> Ash.Query.sort(last_message_sent_at: :desc)
|> Ash.Query.page(limit: 10)
|> Ash.read!()

Running Tests

MIX_ENV=test mix ecto.reset
mix test

Test Results

• ❌ error: load + sort + page: FAILURE
• ✅ ok: load + sort: SUCCESS
• ✅ ok: load + page: SUCCESS
• ✅ ok: sort + page: SUCCESS

File Structure

• lib/my_domain/chat.ex: Chat resource with has_one, calculation, and aggregate
• lib/my_domain/message.ex: Message resource
• test/my_domain/chat_test.exs: Bug reproduction tests