[maxmad64bis]

⚠️ base-red inherited: #15306

Summary

• When a migration file fails with "duplicate column name", the runner used to record the whole file as applied, so a column added later in that file was never created and the routes reading it returned a 500. The runner now replays the file without the ADD COLUMN statements whose column already exists, then records it. This is what fix(migrations): treat duplicate-column ALTER as no-op #1886 asked for (treat a duplicate ALTER as a no-op, per statement).

Related Issues

• Fixes fix(backend): migration runner marks a file as applied on the first "duplicate column name", even when the rest of the file never ran #15235

Validation

• Change type: DB
• Focused tests and category gates from the golden path
• npm run lint — ESLint reports two unused-function errors in migrationRunner.ts (isSearchRequestTypeMigration, applySearchRequestTypeMigration) that are already on the base and not touched here; nothing new in the changed files
• Reconciled with the current active release base; focused checks rerun afterward
• Production-code changes include a new or updated automated test in this PR

Tests Added Or Updated

• tests/unit/db-migrationrunner-duplicate-column.test.ts (new, 5 cases): a file whose first column already exists ends with all its columns; the CREATE TABLE and CREATE INDEX around the duplicate are kept; a second run changes nothing; the helper skips only existing columns, ignores commented-out statements and leaves statements on a table that doesn't exist yet. Four of the five cases fail without the change.
• tests/unit/db-migrationrunner-duplicate-column-leftovers.test.ts (new, 2 cases, maintainer): a replay that fails on an existing table or index falls back to recording the ledger row only, and a second run applies nothing. Both fail without the change (assertion on the fallback helper).
• Re-run unchanged and passing: tests/unit/db/migration-071.test.ts, tests/unit/db-server-tool-executions-migration.test.ts, tests/unit/memory-vec-meta.test.ts, tests/unit/db-migration-runner-extra-dirs.test.ts, tests/unit/db-migrationrunner-constants-split.test.ts, tests/unit/migration-135-numbering-collision.test.ts.

Coverage Notes

• src/lib/db/migrationRunner/schemaState.ts: stripExistingAddColumns and applyMigrationSkippingExistingColumns are covered by db-migrationrunner-duplicate-column.test.ts (helper cases and the two end-to-end runs).
• src/lib/db/migrationRunner.ts: the catch branch that now calls the helper is covered by the same test's end-to-end cases; the other paths keep their existing tests.

Reviewer Notes

• Behavior: Only a file that contains an already-present ADD COLUMN changes behavior: if nothing can be skipped, or the migration doesn't go through the plain-SQL path, the runner still only records the file, as before. If the replay without the existing columns fails for any reason (another duplicate column, a CREATE TABLE or CREATE INDEX that already exists), it logs a warning and records the file as before instead of stopping startup.
• Follow-up: Not covered on purpose: the isSchemaAlreadyApplied cases whose only job is a hasColumn check could probably be simplified later; I left them alone.