[pcapel]

This test shows a bug in ash_sql. The fix is in ash-project/ash_sql#277

A list aggregate with uniq? and a sort on its own field fails with 42P10 when the column is varchar. The existing uniq_aggregate_sort_test.exs tests use comments.title, which is text, so they don't hit it. This adds a label attribute to Comment with migration_types(label: {:varchar, 255}), a uniq_comment_labels aggregate on Post, and a test next to its text twin.

The new test fails on ash_sql main and passes with the fix. The other five tests in the file pass either way.

mix test.generate_migrations created the migration and snapshot for test_repo only. The PG18 run reported no changes, because use_builtin_uuidv7_function?/0 now defaults to false and both runs resolve to test_repo. That matches the other recent test migrations.

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[pcapel]

Comparing the CI failures here with existing failures, the only new one is the regression test as expected pending ash-project/ash_sql#277 merging and releasing.

[zachdaniel]

🚀 Thank you for your contribution! 🚀