## Migrate Supabase database: Transactional workflows

Move PostgreSQL data from Supabase database to Ample, one component at a time. Destination verified on Ample: an optimistic version check and an event row written in the same transaction, a stale update rejected, and a history query over the application-owned events (history=2 conflict=rejected).

### Source procedure:
Take a logical backup with `pg_dump -Fc` using the direct (non-pooled) connection string. Not migrated automatically: Supabase Auth, Storage, Realtime, Edge Functions and row-level security policies tied to Supabase roles are not migrated by a database move.

### Cutover:
Freeze writes at the source with the user's go-ahead, take the final dump, restore, validate counts and checksums, redeploy the app with the managed DATABASE_URL, keep the Supabase project until confirmed.

### Rollback:
Keep the source untouched until you confirm; nothing at the source is changed or deleted by this guide.

### Workflow Steps:
1. **Inventory the source**  
   List what Supabase database provides beyond the component you are moving. Out of scope here: Supabase Auth, Storage, Realtime, Edge Functions and row-level security policies tied to Supabase roles are not migrated by a database move.

2. **Source step 1**  
   Take a logical backup with `pg_dump -Fc` using the direct (non-pooled) connection string.

3. **Source step 2**  
   Check extensions and Supabase-managed schemas (`auth`, `storage`, `realtime`) in the dump; only your application schema moves.

4. **Source step 3**  
   Restore into a scratch managed database first and compare row counts.

5. **Provision and restore**  
   Deploy the app once so a managed PostgreSQL 16 database exists (or create one with `ample database create --engine postgres`), then restore the dump with `pg_restore` using its connection string; keep migrations idempotent.

Command: `ample database create --name <name> --engine postgres`

6. **Validate before cutover**  
   Run the app's own checks and, for data, compare counts and checksums; the example checks are the pattern self-tests (/p/transactional-workflows).

7. **Cut over**  
   Freeze writes at the source with the user's go-ahead, take the final dump, restore, validate counts and checksums, redeploy the app with the managed DATABASE_URL, keep the Supabase project until confirmed.

8. **Rollback**  
   Point DNS or configuration back to the source. The source was never modified; deletion is a separate, user-executed step after validation.

### Examples:
- **Express pattern fixture (destination)**  
  Verified destination basis: transactional workflows.  
  Source reference: `tests/deploy-canaries/express-patterns`

### Success Checks:
- Destination app responds on its public URL.
- Transactional-workflows check from the destination example.
- Data or object counts and checksums match the source.

### Limitations:
- Documentation only: nothing is executed automatically and no execution binding is offered.
- The source-side procedure is documented from Supabase database's standard tooling and was not executed in this catalog's evidence; the destination side was verified with the pattern fixture.
- No full source-product parity is claimed: Supabase Auth, Storage, Realtime, Edge Functions and row-level security policies tied to Supabase roles are not migrated by a database move.

### Cost Estimate:
- **Currency:** USD  
  **Monthly Amount:** 10.0 (authoritative)  
  **Basis:** Size prices from pricing.toml (loaded by the API) at build revision 1ac5595375130d45290090e82ed0f554ccd45405-dirty.  
  - Components:
    - **App server**: size `s-1vcpu-1gb`, quantity `1`, monthly amount `5.0`.
    - **Managed PostgreSQL database**: size `s-1vcpu-1gb`, quantity `1`, monthly amount `5.0`.
  - Note: Destination always-on monthly price of the tested sizes; apps auto-pause when idle. Source costs are unknown to Ample.