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Restore the Database to a Point in Time

Use point-in-time recovery to restore to 5 minutes before the bad migration so data loss is minimized.

~30 mindatabasebackuppitr

Task

Apply pg_restore --restore-to-timestamp='2026-10-25 14:55:00' backup.dump so the schema change is safe, reversible, and does not lock the table during peak traffic.

When to use this

A migration deploys pg_restore --restore-to-timestamp='2026-10-25 14:55:00' backup.dump during peak hours, takes a 40-second lock, and causes a connection pool exhaustion.

Prerequisites

  • A database with migration tooling configured
  • A staging environment mirroring production schema

Steps

1. Configure pg_restore --restore-to-timestamp='2026-10-25 14:55:00' backup.dump in the project configuration file with the recommended defaults.

pg_restore --restore-to-timestamp='2026-10-25 14:55:00' backup.dump

Expected output: The configuration is accepted and pg_restore --restore-to-timestamp='2026-10-25 14:55:00' backup.dump runs without errors on the first invocation.

2. Run the check locally to verify pg_restore --restore-to-timestamp='2026-10-25 14:55:00' backup.dump produces the expected result before pushing.

pnpm test

Expected output: Local run matches CI behavior; no surprises after push.

3. Add the gate to the CI pipeline so pg_restore --restore-to-timestamp='2026-10-25 14:55:00' backup.dump blocks merge on failure.

- name: Run add backup pit restore
  run: pnpm test

Expected output: Pull requests with failing pg_restore --restore-to-timestamp='2026-10-25 14:55:00' backup.dump are blocked from merging.

Troubleshooting

Problem

The check passes locally but fails in CI

Solution

Pin dependency versions and the runtime to match CI exactly; reproduce with the same Docker image or act.

Problem

Configuration is rejected with a schema error

Solution

Check the tool version matches the config schema; older versions may not support newer fields.

Limitations

  • The gate only runs on events that trigger the workflow; locally pushed commits bypass it.
  • Configuration drift is possible if someone edits settings outside version control.

Make migrations safe

Start by measuring the problem. Use point-in-time recovery to restore to 5 minutes before the bad migration so data loss is minimized. The most common mistake is adding the gate without first confirming it catches the issue you care about. Run pg_restore –restore-to-timestamp=‘2026-10-25 14:55:00’ backup.dump against the current codebase and inspect the output before wiring it into CI.

pg_restore --restore-to-timestamp='2026-10-25 14:55:00' backup.dump

Verify and roll back

Once the gate is in place, make failures actionable. A failing pg_restore –restore-to-timestamp=‘2026-10-25 14:55:00’ backup.dump should point to the exact file and line, not a generic error. Pin the tool version in the lockfile so a upstream release does not silently change behavior. Review the gate output in every pull request just like a test result.