erDiagram
    USER {
        int id PK
        string email UK
        string name
        datetime created_at
    }
    ORDER {
        int id PK
        int user_id FK
        decimal total
        string status
        datetime placed_at
    }
    ORDER_ITEM {
        int id PK
        int order_id FK
        int product_id FK
        int quantity
        decimal unit_price
    }
    PRODUCT {
        int id PK
        string name
        decimal price
        int stock
    }

    USER ||--o{ ORDER : places
    ORDER ||--|{ ORDER_ITEM : contains
    PRODUCT ||--o{ ORDER_ITEM : "is in"