# Are our database changes safe before we merge?

Prompt · Rebuild and safe change · PG17

A migration, or a change to functions, views, RLS, types or column meaning, is about to ship.

## Prompt

```text
Review this database change against the live schema, existing consumers, prior migrations and deployment process. Establish whether it preserves current records, supports old and new application versions during rollout, and can be verified on an isolated database. Identify the smallest necessary migration and a realistic recovery path before approving it.
```

**What it returns:** The migration diff, the consumers it touches, how old and new app versions coexist during rollout, locks and rollback, and a replay on a separate database.

**Skip it when:** The change touches no schema, functions or policies.

**Avoid:** Claiming a rollback exists because the application code can be reverted.

**Tools:** Needs: the repository, read-only access to the live schema and a separate database to replay the migration. Helps: pgTAP and, on Supabase, Advisors and branches.

**Works on:** Any PostgreSQL host: Supabase, Neon, RDS, Cloud SQL or self-hosted.

**Changes:** Tests on a separate copy

**Sessions:** Look first, then fix in a new session

## Related

- [Database changes during a deploy](https://www.atlasscope.dev/prompts/database-changes-during-a-deploy): Checks that each database change works with the old code that is still live while a release finishes.
- [Why production might not match main](https://www.atlasscope.dev/prompts/why-production-might-not-match-main): Lists every way 'merged' can fail to mean 'live'.
- [Settings that differ in production](https://www.atlasscope.dev/prompts/settings-that-differ-in-production): Finds settings that behave differently in production than anyone expects.
- [Can we rebuild this database from its sources?](https://www.atlasscope.dev/prompts/can-we-rebuild-this-database-from-its-sources): You worry about disaster recovery, production-only state, or whether the data could be rebuilt.

Source: https://www.atlasscope.dev/prompts/are-our-database-changes-safe-before-we-merge