docs: ADR-0032 Amendment 1 — empirical scope of column-origin metadata

§12 was written conservatively, classifying projection items
structurally and listing "subquery expressions" alongside
arithmetic / CASE as cases that stay None. The Phase-2 plan's
Open Question 1 captured the matching uncertainty about CTEs
and scalar subqueries.

A throwaway probe against the pinned bundled SQLite +
rusqlite 0.39.0 (with the `column_metadata` feature) settles
the question across 20 representative query shapes. The
engine's column_table_name / column_origin_name metadata
follows through non-recursive CTEs (SELECT *, bare-ref,
qualified-ref, and (col-list)-renamed bodies; CTE chains),
scalar subqueries (aliased and unaliased), derived tables
(out of scope per §13 OOS-1 but useful to note), all four
set ops, multi-table JOIN projections, and IN-subquery
WHERE clauses (the inner subquery does not affect the
outer projection's origin).

The structural-None classes reduce to computed projections
(function calls, arithmetic, CASE, literals, wildcards —
expected and pedagogically obvious) and recursive CTE result
columns (the one structural surprise — the recursive
temporary table has no base-column origin to point at).

Amendment 1 supersedes §12's "Resolution rule" with a simpler
engine-driven rule: trust column_table_name(i) /
column_origin_name(i) verbatim, with no grammar-side
structural classification. The speculative MatchedPath-walk
fallback is moot. The Phase-2 plan's sub-phase 2f exit gate
gains explicit positive assertions for CTE pass-through and
scalar-subquery type recovery, and a new explicit negative
assertion for the recursive-CTE limitation.

README.md index entry extended in the same style as ADR-0027's
Amendment-1 line. Closes Plan §Open-1.
This commit is contained in:
claude@clouddev1
2026-05-20 11:04:48 +00:00
parent 3db292c795
commit e032f01b2d
2 changed files with 106 additions and 1 deletions
+1 -1
View File
@@ -37,4 +37,4 @@ This directory contains the project's ADRs, recorded per
- [ADR-0029 — Column constraints (NOT NULL / UNIQUE / CHECK / DEFAULT)](0029-column-constraints.md) — **Accepted**, the four column-level constraints declared in the column-spec suffix (`create table` / `add column`) and modified on existing columns via `add constraint …` / `drop constraint …`; a pre-flight dry-run guards populated columns; `CHECK` reuses the ADR-0026 expression grammar via `Subgrammar` (`C3`)
- [ADR-0030 — Advanced mode: the standard-SQL surface](0030-advanced-mode-sql-surface.md) — **Accepted**, SQL added as grammar *within the unified grammar tree* (ADR-0024), not a separate batch parser — so SQL gets the same completion / highlighting / hints / parse-errors as the DSL; mode gates the SQL forms; DDL routes through the typed `Command` executor (metadata + type vocabulary preserved), DML and `SELECT` execute as validated SQL; engine-neutral posture, the DSL→SQL teaching echo; supersedes ADR-0001's `sqlparser-rs` reservation; phased plan (`Q1` / `Q2` / `Q4`)
- [ADR-0031 — The SQL expression grammar](0031-sql-expression-grammar.md) — **Accepted**, the stratified SQL expression grammar fragment commissioned by ADR-0030 §3: a single precedence ladder (`OR`/`AND`/`NOT`, the comparison/`LIKE`/`IN`/`BETWEEN`/`IS NULL` predicate set, arithmetic incl. `||`, function calls, `CASE`) — the superset of ADR-0026's DSL `WHERE` grammar, authored as a parallel fragment so simple mode is untouched; pure validation, builds **no** AST (consumers run/store SQL as text per ADR-0030 §4/§6); reuses ADR-0026's `Subgrammar` recursion + depth cap unchanged; subquery expressions and qualified column refs deferred to ADR-0030 Phase 2
- [ADR-0032 — The full SQL `SELECT` grammar](0032-sql-select-grammar.md) — **Accepted**, the Phase-2 grammar commissioned by ADR-0030 §3: full `SELECT` with `INNER`/`LEFT`/`RIGHT`/`FULL OUTER`/`CROSS` joins, `GROUP BY`/`HAVING`, all four set ops (`UNION`/`UNION ALL`/`INTERSECT`/`EXCEPT`), `WITH` and `WITH RECURSIVE` CTEs, `LIMIT … OFFSET`, `DISTINCT`, `t.*`, and bare-alias projection (lifting Phase-1 §4.2); additive extensions to ADR-0031's `sql_expr` for scalar subqueries, `IN (SELECT …)`, `[NOT] EXISTS`, and qualified column refs (redeeming ADR-0031 §7 OOS-1/OOS-2); grammar-recursion via `Subgrammar(&SQL_SELECT_COMPOUND)` reuses ADR-0026's `MAX_SUBGRAMMAR_DEPTH = 64` cap unchanged; **softens ADR-0030 §8's "ambient assistance comes for free" claim**: completion scope needs new `WalkContext` accumulators (a `from_scope_stack` of `ScopeFrame`s holding `from_scope` / `cte_bindings` / `projection_aliases`), a **new walker node variant `Node::ScopedSubgrammar(&Node)`** as the push/pop trigger (existing `Node::Subgrammar` unchanged so DSL `Expr` and `sql_expr` recursion are unaffected), qualified-prefix completion narrowing, body-projection-derived CTE column resolution (so `SELECT *` and explicit-projection CTE bodies both yield real column completion past `cte_alias.|`), and a **post-walk fixup pass** that re-resolves projection-list identifier highlighting/validity once `FROM` is parsed (the projection-before-FROM problem); classifies every Phase-2 validation case against ADR-0027's ERROR/WARNING guideline (§11): five new `diagnostic.*` keys for parse-time-detectable cases (unknown qualifier, ambiguous column, projection-alias misplaced, CTE/compound arity mismatch) plus eight `engine.*` translation keys; a MatchedPath-walking predicate-warnings variant that closes the Phase-1 gap where SQL `WHERE` expressions emitted no `LIKE`-on-numeric / `= NULL` / type-mismatch warnings (ADR-0027 Amendment 1 finally extends to the SQL surface); adds a worker-side post-prepare type-resolution pass via engine column-origin metadata so bare column refs recover their playground type (partially lifting Phase-1 §4.5, the bool→0/1 case) — `Cargo.toml` gains `column_metadata` to rusqlite features (verified against pinned 0.39.0); `__rdbms_*` rejection extended to every new table-source slot
- [ADR-0032 — The full SQL `SELECT` grammar](0032-sql-select-grammar.md) — **Accepted**, the Phase-2 grammar commissioned by ADR-0030 §3: full `SELECT` with `INNER`/`LEFT`/`RIGHT`/`FULL OUTER`/`CROSS` joins, `GROUP BY`/`HAVING`, all four set ops (`UNION`/`UNION ALL`/`INTERSECT`/`EXCEPT`), `WITH` and `WITH RECURSIVE` CTEs, `LIMIT … OFFSET`, `DISTINCT`, `t.*`, and bare-alias projection (lifting Phase-1 §4.2); additive extensions to ADR-0031's `sql_expr` for scalar subqueries, `IN (SELECT …)`, `[NOT] EXISTS`, and qualified column refs (redeeming ADR-0031 §7 OOS-1/OOS-2); grammar-recursion via `Subgrammar(&SQL_SELECT_COMPOUND)` reuses ADR-0026's `MAX_SUBGRAMMAR_DEPTH = 64` cap unchanged; **softens ADR-0030 §8's "ambient assistance comes for free" claim**: completion scope needs new `WalkContext` accumulators (a `from_scope_stack` of `ScopeFrame`s holding `from_scope` / `cte_bindings` / `projection_aliases`), a **new walker node variant `Node::ScopedSubgrammar(&Node)`** as the push/pop trigger (existing `Node::Subgrammar` unchanged so DSL `Expr` and `sql_expr` recursion are unaffected), qualified-prefix completion narrowing, body-projection-derived CTE column resolution (so `SELECT *` and explicit-projection CTE bodies both yield real column completion past `cte_alias.|`), and a **post-walk fixup pass** that re-resolves projection-list identifier highlighting/validity once `FROM` is parsed (the projection-before-FROM problem); classifies every Phase-2 validation case against ADR-0027's ERROR/WARNING guideline (§11): five new `diagnostic.*` keys for parse-time-detectable cases (unknown qualifier, ambiguous column, projection-alias misplaced, CTE/compound arity mismatch) plus eight `engine.*` translation keys; a MatchedPath-walking predicate-warnings variant that closes the Phase-1 gap where SQL `WHERE` expressions emitted no `LIKE`-on-numeric / `= NULL` / type-mismatch warnings (ADR-0027 Amendment 1 finally extends to the SQL surface); adds a worker-side post-prepare type-resolution pass via engine column-origin metadata so bare column refs recover their playground type (partially lifting Phase-1 §4.5, the bool→0/1 case) — `Cargo.toml` gains `column_metadata` to rusqlite features (verified against pinned 0.39.0); `__rdbms_*` rejection extended to every new table-source slot; Amendment 1 narrows §12's resolution rule from a grammar-side structural classification to "trust the engine's column-origin metadata verbatim" after an empirical probe showed origin metadata follows through non-recursive CTEs, scalar subqueries, derived tables, set ops, and joins — the one structural exception is recursive CTE result columns, which return None and stay typeless