# Database diagram

> Create database diagrams (ER diagrams) showing tables, columns, primary keys, foreign keys, and relationships.

Source: https://mockflow.com/developers/reference/item-types/database-diagram

Send `"type": "database_diagram"`.

Create database diagrams (ER diagrams) showing tables, columns, primary keys, foreign keys, and relationships.

Also available as the MCP tool `render_database`. The same payload works through either surface.

### Fields

- `title` (string): A short title for the schema, shown as the frame header (e.g. "E-commerce Database").
- `class` (string, required): Always 'GraphLinksModel'
- `category` (enum<string>, required): Must be 'database'. One of `database`.
- `nodeDataArray` (object[], required): Array of database tables with key, text, color, fillColor, and columns array
    - `key` (string, required): Unique table identifier
  - `text` (string, required): Table display name
  - `color` (string): Header border color
  - `fillColor` (string): Header background color
  - `columns` (object[], required): Array of column definitions
- `linkDataArray` (object[], required): Array of foreign key relationships between tables
    - `from` (string, required): Source table key (table with FK)
  - `to` (string, required): Target table key (referenced table)
  - `text` (string): Relationship label (e.g., "user_id → id")
  - `relation` (enum<string>, required): Cardinality — drives the crow's-foot arrowheads. one-to-many = one row in "from" relates to many rows in "to". One of `one-to-one`, `one-to-many`, `many-to-one` or `many-to-many`.

## Example

```json
{
  "type": "database_diagram",
  "data": {
    "title": "Q4 Launch Planning",
    "class": "string",
    "category": "database",
    "nodeDataArray": [
      {
        "key": "string",
        "text": "Interview 5 users",
        "color": "string",
        "fillColor": "string",
        "columns": [
          {
            "name": "Q4 Launch Planning",
            "type": "string",
            "pk": false,
            "fk": false
          }
        ]
      }
    ],
    "linkDataArray": [
      {
        "from": "string",
        "to": "string",
        "text": "Interview 5 users",
        "relation": "one-to-one"
      }
    ]
  }
}
```