fix: analyze a copy of the view body in CREATE VIEW hook - #231
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The pg_ducklake utility hook parse-analyzes every CREATE VIEW body to detect duckdb_row target columns (RewriteDuckdbRowViewStmt). It fed the ViewStmt's raw query directly to parse_analyze, but parse analysis rewrites the raw tree in place: transformFromClauseItem replaces a JoinExpr's larg/rarg with RangeTblRef nodes, and transformSubLink replaces SubLink->subselect (a raw SelectStmt) with an analyzed Query. For any view we do not end up rewriting (the common case), the hook returned without using the analyzed result, leaving stmt->query corrupted. DefineView then re-ran parse analysis on the mutated tree and failed: - #229: explicit JOIN/LEFT JOIN -> "unrecognized node type: 63" (transformFromClauseItem sees a RangeTblRef where a raw FROM item is expected). - #230: EXISTS / IN (SELECT) / correlated subquery -> "unexpected non-SELECT command in SubLink" (transformSubLink sees subselect already a Query). CTE views could crash the backend outright. Both issues share this single root cause. Fix: parse-analyze a copyObject of stmt->query so the original raw tree stays pristine for DefineView. Plain SELECT and comma-join views worked before only because those shapes are not mutated in place. Adds create_view_shapes regression test: JOIN, LEFT JOIN, EXISTS, correlated scalar subquery, IN (SELECT), CTE, UNION, and LATERAL views over heap tables, plus JOIN and EXISTS over ducklake tables, each verifying SELECT returns correct rows. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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With pg_ducklake installed, CREATE VIEW fails for any view body containing an explicit JOIN (ERROR: unrecognized node type: 63) or a subquery -- EXISTS, IN (SELECT ...), or a correlated subquery in the SELECT list (ERROR: unexpected non-SELECT command in SubLink). This hits pure heap tables too, no ducklake table involved, and views with CTEs crashed the backend outright.
The CREATE VIEW utility hook parse-analyzes the view body to detect duckdb_row target columns, but it fed the ViewStmt's raw query tree directly to parse_analyze. PostgreSQL's parse analysis mutates the raw tree in place (JoinExpr larg/rarg become RangeTblRef nodes, SubLink->subselect becomes an analyzed Query), so for the common case where the hook does not rewrite the view, DefineView then re-analyzed a corrupted tree and failed.
The fix is one line: analyze a copyObject of the query so the original raw tree stays pristine for DefineView.
Adds a create_view_shapes regression test covering eight view shapes over heap tables (JOIN, LEFT JOIN, EXISTS, correlated scalar subquery, IN (SELECT), CTE, UNION, LATERAL) plus JOIN and EXISTS views over ducklake tables; all of them fail or crash on unfixed code. Full regression suite passes (52/52).
Fixes #229
Fixes #230
Forward-port to main is needed.
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