# Create & import


Create a PostgreSQL service in the [GUI](#create-in-the-gui), or describe it in YAML and [import](#import-with-yaml) it through the GUI or zCLI. Both paths configure the same things; the YAML route is repeatable and versionable.

## Create in the GUI

Go to your project dashboard and choose **Add new service** in the **Services** block:

[Video: /vids/services/postgres.webm](/vids/services/postgres.webm)

The wizard asks for four things:

### Version

### Hostname

A unique service identifier, like `db`, `sql`, or `postgresql`. Maximum 25 characters, lowercase ASCII letters (a-z) and numbers (0-9) only, unique within the project.

### Deployment mode

**Highly Available** (a 3-node cluster, recommended for production) or **Single container** (lower cost, no redundancy). See [Deployment modes](/postgresql/overview#deployment-modes) for the comparison.

### Scaling profile and resources

Pick a [scaling profile](/postgresql/how-to/scale#scaling-profiles) matched to your workload (OLTP, OLAP, or write-heavy). The profile sets the autoscaling defaults and tunes the PostgreSQL configuration; on top of it you can set the CPU mode (shared or dedicated) and minimum/maximum limits for CPU, RAM, and disk. See [Scale & profiles](/postgresql/how-to/scale) for details.

:::caution
The **hostname** and **deployment mode** are fixed once the service is created. The scaling **profile** and resource limits can be changed at any time.
:::

## Import with YAML

Zerops uses a YAML file to describe services declaratively. You can paste it in the GUI (**Import services** in the left menu of your project) or import it with the [zCLI](/references/cli).

### Add a service to an existing project

```yaml title="zerops-import.yaml"
services:
  - hostname: db
    # postgresql:{single|ha}@{version}
    type: postgresql:single@18
    # optional: autoscaling profile, see Scale & profiles
    profile: oltp-staging
```

With zCLI:

```sh
zcli project service-import zerops-import.yaml
```

The command is interactive: it lists your projects and lets you pick which one to import into. You can also pass the project ID directly with `-P`:

```sh
Usage:
  zcli project service-import importYamlPath [flags]

Flags:
  -h, --help                Help for the project service import command.
  -P, --project-id string   If you have access to more than one project, you must specify the project ID for which the
                           command will be executed.
```

### Create a new project

A project import additionally contains the `project:` section:

```yaml title="zerops-import.yaml"
project:
  name: my-project
  # optional: project description and tags
  description: A project with a PostgreSQL database
  tags:
    - DEMO
    - ZEROPS

services:
  - hostname: db
    type: postgresql:ha@18
    profile: oltp-production
    # optional: override the profile's autoscaling defaults
    verticalAutoscaling:
      cpuMode: DEDICATED
      minCpu: 2
      maxCpu: 5
      minRam: 2
      maxRam: 24
      minDisk: 6
      maxDisk: 50
      startCpuCoreCount: 3
      minFreeRamGB: 0.5
      minFreeRamPercent: 20
  - hostname: dbstaging
    type: postgresql:single@18
    profile: oltp-staging
```

```sh
zcli project project-import zerops-import.yaml
```

The project name comes from the YAML, so the command doesn't take one. If you are a member of more than one organization (called *client* in the GUI), pass the ID with `--org-id`; you'll find it under the client name on the project dashboard.

```sh
Usage:
  zcli project project-import importYamlPath [flags]

Flags:
  -h, --help                Help for the project import command.
      --org-id string        If you have access to more than one organization, you must specify the org ID for which the
                            project will be created.
      --working-dir string   Sets a custom working directory. The default working directory is the current directory. (default "./")
```

:::note
The maximum size of an import YAML is 100 kB. A project import can mix PostgreSQL with [any other service type](/references/import-yaml/type-list).
:::

### Project parameters

The `project:` section is required for a project import. Only one project can be defined.

| Parameter | Description |
| --- | --- |
| **name** | The name of the new project. Duplicates are allowed. |
| **description** | **Optional.** Description of the new project. Maximum 255 characters. |
| **tags** | **Optional.** One or more string tags. Tags have no functional meaning, they only provide better orientation in projects. |

### Service parameters

At least one service in the `services:` section is required.

| Parameter | Description |
| --- | --- |
| **hostname** | The unique service identifier; becomes the database hostname on the project's private network. Maximum 25 characters, lowercase ASCII letters (a-z) and numbers (0-9) only, unique within the project. **Fixed after creation.** |
| **type** | The service type, deployment mode, and version in `postgresql:{single|ha}@{version}` format. The `:single`/`:ha` part selects the deployment mode and is **fixed after creation**; the standalone `mode` field is deprecated. See the list of supported types. |
| **profile** | **Optional.** The autoscaling profile: sets the autoscaling envelope and tunes the PostgreSQL configuration for your workload. Defaults to `oltp-staging` (single) or `oltp-production` (HA). Can be changed at any time in the GUI. |
| **profileOverrides** | **Optional.** Only valid with `profile: custom`; overrides individual PostgreSQL configuration values. See Custom profile for the overridable keys and their units. |
| **verticalAutoscaling** | **Optional.** Overrides the profile's autoscaling defaults. All attributes are optional: `cpuMode` (`SHARED`/`DEDICATED`), `minCpu`/`maxCpu` (cores), `minRam`/`maxRam` (GB), `minDisk`/`maxDisk` (GB), `startCpuCoreCount`, `minFreeRamGB`, `minFreeRamPercent`. See Configure scaling. |