# Reconcilix database migrations

Run all pending migrations explicitly from the project root:

```bash
php tools/migrate.php
```

Rules:

- Migration files use monotonically increasing numeric prefixes.
- Applied files are immutable; corrections require a new migration.
- SHA-256 checksums are stored in `schema_migration`.
- The runner uses a database-scoped advisory lock.
- Migrations are forward-only and never run from the HTTP entry point.
- The configured database must already exist; migrations do not create or select a database.

The SQL migrations are the executable technical projection of DM002. Changes to the persistence model are documented in DM002 first and then represented by a new migration.