Rewrite information_schema.columns to return text for VARCHAR types #40
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- Add transpiler transform to rewrite information_schema.columns queries to use information_schema_columns_compat view (which maps VARCHAR -> text) - Fix: initInformationSchema was never called, now called during connection setup - Add test to verify the rewrite works correctly PostgreSQL clients expect data_type to return 'text' or 'character varying' for string columns, but DuckDB returns 'VARCHAR'. The compat view handles this conversion. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <[email protected]>
When DuckLake is the default database, view creation causes transaction conflicts between concurrent connections. Fix by switching to memory database before creating views, then switching back. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <[email protected]>
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Summary
information_schema.columnsreturningVARCHARinstead oftextfor string columnstextorcharacter varying, but DuckDB returnsVARCHARChanges
transpiler/transform/pgcatalog.go): Rewriteinformation_schema.columns→information_schema_columns_compatserver/server.go):initInformationSchema()was never called - now called during connection setuptranspiler/transpiler_test.go): Verify the rewrite works correctlyHow it works
The
information_schema_columns_compatview (created incatalog.go) wraps DuckDB's nativeinformation_schema.columnsand converts thedata_typecolumn:CASE WHEN UPPER(data_type) = 'VARCHAR' OR UPPER(data_type) LIKE 'VARCHAR(%' THEN 'text' ELSE data_type END AS data_typeThe transpiler now rewrites queries from:
To:
Test plan
🤖 Generated with Claude Code