> ## Documentation Index
> Fetch the complete documentation index at: https://docs.bytebase.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Release

After PR/MR merge, Bytebase creates a release, compares the desired state with current database state, generates migration DDL, and deploys.

## How SDL Release Works

1. **State Comparison** - Bytebase compares your SDL files with current database schema
2. **DDL Generation** - Automatically generates ALTER/DROP statements using topological sort
3. **Migration Execution** - Applies generated DDL to reach desired state
4. **Revision Tracking** - Records new version for future comparisons

## CI/CD Integration

Add `--declarative` flag to enable SDL mode:

<Info>
  Use a compatible `bytebase-action` image. For Bytebase Cloud, use
  `bytebase/bytebase-action:cloud`. For self-hosted Bytebase, replace `:cloud` with your
  Bytebase server version, for example `:3.14.0`.
</Info>

<Tabs>
  <Tab title="GitHub Actions">
    ```yaml theme={null}
    # .github/workflows/release.yml
    name: SDL Release
    on:
      push:
        branches: [main]
        paths:
          - 'schema/**'

    jobs:
      release:
        runs-on: ubuntu-latest
        steps:
          - uses: actions/checkout@v4

          - name: Deploy SDL
            uses: bytebase/sql-review-action@v1
            with:
              command: rollout
              bytebase-url: ${{ secrets.BYTEBASE_URL }}
              bytebase-token: ${{ secrets.BYTEBASE_SERVICE_ACCOUNT_TOKEN }}
              file-pattern: 'schema/**/*.sql'
              project: projects/my-project
              targets: instances/prod/databases/mydb
              declarative: true
    ```
  </Tab>

  <Tab title="GitLab CI">
    ```yaml theme={null}
    # .gitlab-ci.yml
    sdl-rollout:
      image: bytebase/bytebase-action:cloud
      stage: deploy
      only:
        - main
      script:
        - |
          bytebase-action rollout \
            --url $BYTEBASE_URL \
            --service-account $BYTEBASE_SERVICE_ACCOUNT \
            --service-account-secret $BYTEBASE_SERVICE_ACCOUNT_SECRET \
            --file-pattern "schema/**/*.sql" \
            --project projects/my-project \
            --targets instances/prod/databases/mydb \
            --declarative
    ```
  </Tab>

  <Tab title="Azure DevOps">
    ```yaml theme={null}
    # azure-pipelines.yml
    jobs:
      - job: SDLRelease
        pool:
          vmImage: 'ubuntu-latest'
        steps:
          - task: Docker@2
            inputs:
              command: run
              arguments: >
                bytebase/bytebase-action:cloud
                rollout
                --file-pattern "/workspace/schema/**/*.sql"
                --project projects/my-project
                --targets instances/prod/databases/mydb
                --declarative
    ```
  </Tab>
</Tabs>

## Version Management

SDL automatically generates versions using timestamp format `YYYYMMDD.HHMMSS`:

```
Release 2025-01-15 10:30:00 → Version: 20250115.103000
Release 2025-01-20 14:15:00 → Version: 20250120.141500
```

All files in a release share the same version. Bytebase compares this version with the latest revision to determine if deployment is needed.

## Migration Generation Example

**Current Database:**

```sql theme={null}
CREATE TABLE public.users (
    id INTEGER PRIMARY KEY,
    username TEXT NOT NULL
);
```

**New SDL:**

```sql theme={null}
CREATE TABLE public.users (
    id INTEGER,
    username TEXT NOT NULL,
    email TEXT NOT NULL,
    CONSTRAINT users_pkey PRIMARY KEY (id),
    CONSTRAINT users_email_key UNIQUE (email)
);

CREATE INDEX idx_users_email ON public.users(email);
```

**Generated Migration:**

```sql theme={null}
-- Bytebase automatically generates:
ALTER TABLE public.users ADD COLUMN email TEXT NOT NULL;
ALTER TABLE public.users ADD CONSTRAINT users_email_key UNIQUE (email);
CREATE INDEX idx_users_email ON public.users(email);
```

***

## Next Steps

<CardGroup cols={2}>
  <Card title="Limitations" icon="triangle-alert" href="/gitops/state-based-workflow/limitations">
    Understand SDL constraints and considerations
  </Card>

  <Card title="Best Practices" icon="lightbulb" href="/gitops/best-practices/overview">
    Production-ready workflow patterns
  </Card>
</CardGroup>