What it does wrong — confirms KL-7 generalizes beyond the obvious case
A CTE that collides in name with a physical table drops that table anywhere in the procedure, even in a completely unrelated statement that never references the CTE at all.
;WITH Product AS (SELECT c.CaseId FROM dbo.CaseFile c)
SELECT p.CaseId FROM Product p;
SELECT sp.Id FROM dbo.Product sp;
The Product CTE is built from an entirely different table (dbo.CaseFile). A second, totally separate statement directly queries the real dbo.Product — never through the CTE. dbo.Product still vanishes from the report.
Why it matters
This confirms the root cause behind KL-7 (see that issue) is not a narrow edge case — the exclusion check (base in cte_names) is a blunt, procedure-wide set-membership test with no locality. It drops every table sharing that bare name anywhere in the procedure, regardless of whether it has any relationship to the colliding CTE.
Test
Pinned as a strict-xfail: tests/test_known_limitations.py::test_KL7b_collision_drops_unrelated_same_named_table_anywhere_in_procedure.
Likely same fix as KL-7 — see that issue. Filed separately because each has its own pinned regression test and its own fixture (tests/fixtures/cte_table_collision_variant.sql).
What it does wrong — confirms KL-7 generalizes beyond the obvious case
A CTE that collides in name with a physical table drops that table anywhere in the procedure, even in a completely unrelated statement that never references the CTE at all.
The
ProductCTE is built from an entirely different table (dbo.CaseFile). A second, totally separate statement directly queries the realdbo.Product— never through the CTE.dbo.Productstill vanishes from the report.Why it matters
This confirms the root cause behind KL-7 (see that issue) is not a narrow edge case — the exclusion check (
base in cte_names) is a blunt, procedure-wide set-membership test with no locality. It drops every table sharing that bare name anywhere in the procedure, regardless of whether it has any relationship to the colliding CTE.Test
Pinned as a strict-xfail:
tests/test_known_limitations.py::test_KL7b_collision_drops_unrelated_same_named_table_anywhere_in_procedure.Likely same fix as KL-7 — see that issue. Filed separately because each has its own pinned regression test and its own fixture (
tests/fixtures/cte_table_collision_variant.sql).