<br />

Your Data Connect projects consist of two major infrastructure
elements:

- One or more Data Connect service instances
- One or more Cloud SQL for PostgreSQL instances

This guide discusses how to set up and manage your Data Connect
service instances, and introduces how to manage your associated Cloud SQL
instances.

## Configure regions for Firebase Data Connect

Projects that use Data Connect require a location setting.

When you create a new Data Connect service instance, you're prompted
to select the location of the service.
| **Note:** The locations of your Data Connect services don't affect the options for locations needed for other Firebase products you might have in your project, like your default Cloud Firestore location.

### Available locations

Data Connect services can be created in the following
[regions](https://cloud.google.com/docs/geography-and-regions).
| **Note:** Cloud SQL for PostgreSQL instances must be provisioned in the same location as their associated Data Connect instance.

- asia-east1
- asia-east2
- asia-northeast1
- asia-northeast2
- asia-northeast3
- asia-south1
- asia-southeast1
- asia-southeast2
- australia-southeast1
- australia-southeast2
- europe-central2
- europe-north1
- europe-southwest1
- europe-west1
- europe-west2
- europe-west3
- europe-west4
- europe-west6
- europe-west8
- europe-west9
- me-west1
- northamerica-northeast1
- northamerica-northeast2
- southamerica-east1
- southamerica-west1
- us-central1
- us-east1
- us-east4
- us-south1
- us-west1
- us-west2
- us-west3
- us-west4

| Data Connect's Vertex AI integration is not supported for CloudSQL for PostgreSQL instances deployed in:
|
| - asia-northeast2
| - asia-southeast2
| - australia-southeast2
| - northamerica-northeast2
| - southamerica-west1
| - us-west2
| - us-west3

## Manage Data Connect service instances

### Create services

To create a new service, use the Firebase console or run the local project
initialization using the Firebase CLI. These workflows create a new
Data Connect service.

These flows also guide you through:

- Provisioning a new Cloud SQL instance (no-cost tier)
- Linking an existing Cloud SQL instance to Data Connect (Blaze plan)

| **Note:** Cloud SQL for PostgreSQL instances must be provisioned in the same location as their associated Data Connect instance. If your application needs Cloud SQL instances in multiple regions, the Firebase CLI can help deploy the same schema, queries and mutations to the many data connect services in each region.

### Manage users

Data Connect provides tools to manage user access that follow the
the *principle of least privilege* (grant each user or service account the
minimum necessary permissions to support needed functionality) and the notion of
*role-based access control (RBAC)* (with predefined roles to manage database
permissions, simplifying security management).

To add project members as users who can modify Data Connect
instances in your project, use the Firebase console to select appropriate
predefined user roles.
| **Note:** Data Connect services and Cloud SQL for PostgreSQL are separate components of your Data Connect project. You administer each component separately. For example, you might add Data Connect users with permissions to delete schemas, but this would not grant them the ability to [perform backups of a PostgreSQL database](https://firebase.google.com/docs/data-connect/manage-services-and-databases#administer-cloud).

These roles grant permissions using Identity and Access Management (IAM). A
role is a collection of permissions. When you assign a role to a project member,
you grant that project member all the permissions that the role contains. See
more information in:

- The [overview of Firebase IAM roles](https://firebase.google.com/docs/projects/iam/overview)
- The detailed list of [Data Connect roles](https://firebase.google.com/docs/data-connect/configuration-reference#iam-configuration)

#### Choose roles to enable specific workflows

IAM roles enable Firebase CLI workflows to let you manage your
Data Connect projects.

| CLI command, other workflow | Role(s) required |
|---|---|
| `firebase init dataconnect` | - No permissions (when not linking a Cloud SQL instance) - roles/cloudsql.admin (when creating a Cloud SQL instance) |
| `firebase deploy ---only dataconnect` | - firebasedataconnect.connectors.\* - firebasedataconnect.services.\* - firebasedataconnect.schemas.\* - roles/cloudsql.admin |
| `firebase dataconnect:sql:diff` | - firebasedataconnect.services.\* - firebasedataconnect.schemas.\* |
| `firebase dataconnect:sql:migrate` | - roles/cloudsql.admin on the target Cloud SQL instance |
| `firebase dataconnect:sql:grant` | - roles/cloudsql.admin on the target Cloud SQL instance |

## Monitor Data Connect service performance

### Understand service performance

The performance of both the Data Connect service and the Cloud SQL for
PostgreSQL service can affect your experience.

- For the Cloud SQL for PostgreSQL service, refer to general guidance in the [Quotas and limits documentation](https://cloud.google.com/sql/docs/postgres/quotas).
- For the Data Connect service, there is quota for GraphQL requests,
  affecting the rate at which you can call and execute queries:

  - A per-project per-region quota of 24000 GraphQL requests per minute

  If you run into those quota limits, please reach out to
  [Firebase support](https://firebase.google.com/support/troubleshooter/contact)
  to adjust the relevant quota.

### Monitor service performance, usage and billing

You can monitor requests, errors and operation rates, both globally and per
operation in the Firebase console.

## Manage Cloud SQL instances

### Free trial limitations

The following Cloud SQL for PostgreSQL features are not supported in the
[3 month free trial](https://firebase.google.com/docs/data-connect/pricing):

- Different machine tier than **db-f1-micro**
- Changing resources of your instance, such as region, storage, memory, CPU
- PostgreSQL versions other than 15.x
- Read replicas
- Private instance IP address
- High-availability (multi-zone); only single-zone instances are supported
- Enterprise Plus edition
- Automatic backups
- Automatic storage increase.

### Limitations of temporary onboarding databases

When you add Data Connect to your Firebase project, you can begin to
prototype your data model and load data right away, since data will be stored in
a temporary database. Note that your permanent Cloud SQL for PostgreSQL instance
will take from 5 to 20 minutes to provision. Any initial data you load will be
automatically migrated to your permanent PostgreSQL database once it is
provisioned.

This temporary database is great for exploring your schema and CRUD operations.

If you don't want to use the temporary database, wait for your Cloud SQL
instance to be provisioned.

The temporary database is not a PostgreSQL database and does not provide all
PostgreSQL features.

Significant limitations are:

- Database size must be less than 1 MB
- Number of rows per table must be less than 1000
- Less than 1 query per second
- No support for full-text search
- No support for vector embedding generation
- No support for raw SQL features like `@view`, `@col(dataType)`

### Administer Cloud SQL instances

In general, you can manage your Cloud SQL instances using the
[Google Cloud console](https://console.cloud.google.com/sql/instances) to
perform the following workflows.
| **Note:** Data Connect services and Cloud SQL for PostgreSQL are separate components of your Data Connect project. You administer each component separately. For example, you might add Cloud SQL users with permissions to handle PostgreSQL administrative tasks, like performance monitoring and backups, but this would not grant them the ability to [modify Data Connect instances](https://firebase.google.com/docs/data-connect/manage-services-and-databases#manage-data-connect-users).

- Stop and restart Cloud SQL instances
- Create and delete Cloud SQL databases (within instances)
- Start PostgreSQL database instances with flags and use a [variety of extensions](https://cloud.google.com/sql/docs/postgres/extensions)
- Monitor performance with [Cloud SQL observability features](https://cloud.google.com/sql/docs/postgres/observability) in the [Google Cloud console](https://console.cloud.google.com/monitoring?project=_)
- Manage Cloud SQL access and security with features like IAM, secret manager, data encryption and auth proxy
- Add, delete and administer Cloud SQL users.

For these and other workflows, refer to the
[Cloud SQL for PostgreSQL documentation](https://cloud.google.com/sql/docs/postgres).

### Grant PostgreSQL user roles

Data Connect provides tools to manage user access that follow the
the *principle of least privilege* (grant each user or service account the
minimum necessary permissions to support needed functionality) and the notion of
*role-based access control (RBAC)* (with predefined roles to manage database
permissions, simplifying security management).

In some cases, you might want to connect to the Data Connect-managed
Cloud SQL database directly via a SQL client of your choice using, for example,
Cloud Run, Cloud Functions or GKE.

To enable such connections, you need to grant SQL permissions by:

- Assigning the `roles/cloudsql.client` IAM role to the user or service account that needs to connect to the instance, either from the Google Cloud console or using the gcloud CLI
- Granting the necessary PostgreSQL role using the Firebase CLI

#### Assign the Cloud SQL IAM role

For information on working with Cloud SQL for PostgreSQL to assign IAM
role `roles/cloudsql.client`, see [Roles and permissions](https://cloud.google.com/sql/docs/postgres/roles-and-permissions).

#### Grant PostgreSQL roles

Using the Firebase CLI, you can grant predefined PostgreSQL roles to users
or service accounts associated with your project with the
`firebase dataconnect:sql:grant` command.

For example, to grant the writer role, run this command at the CLI:  

    firebase dataconnect:sql:grant --role writer

For details, refer to the [CLI reference guide](https://firebase.google.com/docs/data-connect/cli-reference#grant-cloudsql-roles).

### Integrate existing Cloud SQL for PostgreSQL databases

The default database provisioning and management flow assumes your project
uses a new (greenfield) databases, and when you invoke `firebase deploy`,
Data Connect will display database schema changes to be made and
performs any migrations after you approve.

For existing (brownfield) databases, you may have your own workflow for
managing schemas and cannot use Data Connect tooling for migrations,
yet would like to use your database in a Data Connect project to take
advantage of its SDK generation for mobile and web, query-based authorization,
client connection management, and more.

This section offers guidance about the latter case: integrating existing
databases with Data Connect.
| **Note:** This discussion assumes you have a CloudSQL for PostgreSQL database and have set up user roles for database administration. If you have a PostgreSQL database you want to migrate to Cloud SQL, you can use the Database Migration Service following [this Cloud SQL for PostgreSQL guide](https://cloud.google.com/database-migration/docs/postgres/quickstart)

#### Integrate an existing database into a Data Connect project

The workflow for integrating an existing database generally involves these steps:

1. During Data Connect project setup in the Firebase console, select the instance and database.
2. Using the Firebase CLI, run the `firebase dataconnect:sql:setup` command
   and decline the option to allow Data Connect to handle SQL migrations.

   To prevent changes to your database schema not driven by your custom tooling,
   the `setup` command will assign appropriate reader and writer roles, but not
   the `owner` role. More information about the `setup` command and
   PostgreSQL roles is available in the [CLI reference guide](https://firebase.google.com/docs/data-connect/cli-reference#cloudsql-management-commands).
3. Write a Data Connect GraphQL schema that matches your database
   schema.

   You can only deploy your GraphQL schema, queries and mutations when your
   GraphQL schema is compatible with your PostgreSQL schema.

   To simplify aligning both schemas, we provide the
   `firebase dataconnect:sql:diff` command, which will provide you with the
   required SQL statements to migrate your database. You can use this to
   iteratively refine your GraphQL schema to match your existing database schema.
4. Moving forward, you can iterate quickly on your GraphQL schema, queries, and
   mutation in your local development environment. Then, when satisfied, you can
   use `firebase dataconnect:sql:diff` to obtain the SQL migration statements
   that you can apply to PostgreSQL using your custom tooling and flows.

5. Alternatively, you might make changes directly to your PostgreSQL database
   first, then try to port them back into your GraphQL schema. We recommend the
   GraphQL-first approach, since there might be cases where the schema changes
   aren't supported. In addition, if you deploy changes that make your PostgreSQL
   schema incompatible with deployed connector queries or mutation, then those
   connectors might stop working or misbehave.