CREATE TABLE в ER-диаграмму

erDiagram
    users ||--o{ orders : "user_id"
    orders ||--o{ order_items : "order_id"
    users {
        serial id PK
        varchar_255_ email UK
        varchar_64_ city
    }
    orders {
        serial id PK
        integer user_id FK
        numeric_10_2_ total
        timestamp created_at
    }
    order_items {
        serial id PK
        integer order_id
        integer product_id
        integer qty
    }