This page describes data migration options in Cloud SQL.

## Database Migration Service

Database Migration Service offers multiple migration paths to serve a wide variety of
use cases:

- [Homogeneous migrations](https://docs.cloud.google.com/database-migration/docs/homogeneous-migrations.md.txt) let you move
  data without changing your database SQL engine from self-managed
  or cloud offerings. Database Migration Service can help you migrate from
  backup files, or take the snapshot for you.

- [Heterogeneous migrations](https://docs.cloud.google.com/database-migration/docs/heterogeneous-migrations.md.txt) from Oracle
  and SQL Server sources to Cloud SQL for PostgreSQL let you convert your
  database objects to PostgreSQL with the assistance of
  Gemini-powered conversion features. These features help ensure
  your database objects' consistency and quality in the converted PostgreSQL
  schemas.

### Database Migration Service in Cloud SQL for PostgreSQL

A special, lightweight migration flow called *quick-start migrations*
is integrated directly into Cloud SQL for PostgreSQL to help expedite
homogeneous migrations from sources that have a private IP address in
your Google Cloud Virtual Private Cloud (such as self-managed databases on
Compute Engine, or Cloud SQL for PostgreSQL instances enabled for
private networking).

In this flow, Database Migration Service can automatically manage all
the networking requirements to connect to your source database.
For more information on quick-start migrations in Cloud SQL for PostgreSQL,
see
[Quick-start migrations guide](https://docs.cloud.google.com/sql/docs/postgres/quick-start-migrations-guide.md.txt).

## Replicate from an external server

Another option for migrating data from an external server
into Cloud SQL is to use replication.
Cloud SQL supports various replication modes
to migrate data into your instance.

For more information, see [About replicating from an external server](https://docs.cloud.google.com/sql/docs/postgres/replication/external-server.md.txt).

To set up Cloud SQL for data migration by using replication, see
[Configure Cloud SQL and the external server for replication](https://docs.cloud.google.com/sql/docs/postgres/replication/configure-replication-from-external.md.txt).

## Limitations

- If your instance has customized backup settings (for example, a [custom backup location](https://docs.cloud.google.com/sql/docs/postgres/backup-recovery/backing-up#locationbackups)), then after you promote the instance, we recommend that you customize your backup settings again. During the promotion process, Cloud SQL resets your backup settings to their default values.
- After you promote an instance, we recommend that you enable [point-in-time recovery](https://docs.cloud.google.com/sql/docs/postgres/backup-recovery/pitr.md.txt).