# Migrate Amazon RDS for PostgreSQL: Text search over records

## Summary
Move PostgreSQL data from Amazon RDS for PostgreSQL to Ample, one component at a time. Destination verified on Ample: a generated tsvector column with a GIN index, ranked websearch queries and a negative query returning nothing (search=ok). Source procedure: Take a logical backup with `pg_dump -Fc` from a network location that can reach the instance. Not migrated automatically: Multi-AZ failover, read replicas, IAM authentication, PITR and Performance Insights have no equivalent on the managed database. Cutover: Freeze writes at the source with the user's go-ahead, take the final dump, restore, validate, redeploy with the managed DATABASE_URL, keep RDS until confirmed. Rollback: keep the source untouched until you confirm; nothing at the source is changed or deleted by this guide.

## Workload
Text search over records

## Migration source
Amazon RDS for PostgreSQL

## Prerequisites
- Authorized access to the Amazon RDS for PostgreSQL source and its export tooling
- An inventory of every component in scope and out of scope
- A validated backup or copy before any cutover
- An Ample account token with servers:write, databases:read

## Workflow Steps
1. **Inventory the source**  
List what Amazon RDS for PostgreSQL provides beyond the component you are moving. Out of scope here: Multi-AZ failover, read replicas, IAM authentication, PITR and Performance Insights have no equivalent on the managed database.

2. **Source step 1**  
Take a logical backup with `pg_dump -Fc` from a network location that can reach the instance.

3. **Source step 2**  
Check the engine major version, extensions and parameter-group settings the app depends on.

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.

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/text-search-over-records).

7. **Cut over**  
Freeze writes at the source with the user's go-ahead, take the final dump, restore, validate, redeploy with the managed DATABASE_URL, keep RDS 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.

## Success Checks
- **Destination app responds on its public URL**  
Kind: http_get
Path: /  
Expect: ample canary express patterns

- **Text-search-over-records check from the destination example**  
Kind: http_get
Path: /p/text-search-over-records
Expect: see the pattern fixture checks

- **Data or object counts and checksums match the source**  
Kind: manual
Expect: operator comparison before cutover

## Limitations
- Documentation only: nothing is executed automatically and no execution binding is offered.
- The source-side procedure is documented from Amazon RDS for PostgreSQL'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: Multi-AZ failover, read replicas, IAM authentication, PITR and Performance Insights have no equivalent on the managed database.
- Verified on the node-22 template at s-1vcpu-1gb; region, compliance and request-duration limits are unknown.
- Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures on the managed side are not verified beyond the pattern checks.