Verify DuckDB ALTER TABLE IF NOT EXISTS default rewrite regression
Produce a minimal, current-version repro for a possible DuckDB regression where ALTER TABLE ADD COLUMN IF NOT EXISTS with DEFAULT rewrites existing rows.
- Impact
- Schema migrations are load-bearing infrastructure. Silent data rewrites in an idempotent migration pattern can corrupt application state.
- Verification
- 10 min review with exact DuckDB versions tested; observed before/after table rows; minimal script under 30 lines
- Output
- minimal reproduction script, version matrix, issue draft or upstream comment
- PR policy
- Do Not Open Pr
- Risk
- Low: This uses local throwaway databases and public packages only. It must not claim a confirmed upstream bug until reproduced on a current release.
- Sources
- DuckDB Python client docs, DuckDB GitHub issues