page:migrate:google cloud sql for postgresql:durable job state

Migrate Google Cloud SQL for PostgreSQL: Durable job state

Move PostgreSQL data from Google Cloud SQL for PostgreSQL to Ample, one component at a time. Destination verified on Ample: a jobs table with a state and attempts counter, processing inside a row-locked transaction, and a second run that is a no-op (job=done attempts=1 idempotent=true).

Source procedure:

Take a logical backup with pg_dump -Fc through the Cloud SQL Auth Proxy or an authorized network.

Not migrated automatically:

Cloud SQL Auth Proxy/IAM authentication, high availability and PITR have no equivalent on the managed database.

Cutover:

Freeze writes with the user's go-ahead, take the final dump, restore, validate, redeploy with the managed DATABASE_URL, keep Cloud SQL 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 Google Cloud SQL for PostgreSQL provides beyond the component you are moving. Out of scope here: Cloud SQL Auth Proxy/IAM authentication, high availability and PITR have no equivalent on the managed database.
2. Source step 1: Take a logical backup with pg_dump -Fc through the Cloud SQL Auth Proxy or an authorized network.
3. Source step 2: Check the engine major version, extensions, and flags 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/durable-job-state).
7. Cut over: Freeze writes with the user's go-ahead, take the final dump, restore, validate, redeploy with the managed DATABASE_URL, keep Cloud SQL 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.

Prerequisites

• Authorized access to the Google Cloud SQL 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.

Tested Configuration

• Template: node-22
• Runtime: node
• Size: s-1vcpu-1gb
• Install: npm install
• Build: npm run build --if-present
• Start: npm run start

Limitations

• Documentation only: nothing is executed automatically, and no execution binding is offered.
• The source-side procedure is documented from Google Cloud SQL 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: Cloud SQL Auth Proxy/IAM authentication, high availability and PITR 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.