tbl_warehouse_items {
        int id
        int quantity
        string productCode

        float pricePerUnit
}

tbl_purchase_orders {
        int id
        int quantity
        string productCode

        float pricePerUnit
}

tbl_deliveries {
        int id
        int quantity
        string productCode

        float pricePerUnit
}

tbl_discounts {
        int id
        int quantity
        string productCode

        float pricePerUnit
}

tbl_invoices {
        int id
        int quantity
        string productCode

        float pricePerUnit
}

tbl_order_items {
        int id
        int quantity
        string productCode

        float pricePerUnit
}

tbl_payments {
        int id
        int quantity
        string productCode

        float pricePerUnit
}

tbl_returns {
        int id
        int quantity
        string productCode

        float pricePerUnit
}


---

```mermaid
erDiagram
    CUSTOMER ||--o{ ORDER : places
    CUSTOMER {
        string name
        string custNumber
        string sector
    }
    ORDER ||--|{ LINE-ITEM : contains
    ORDER {
        int orderNumber
        string deliveryAddress
    }
    LINE-ITEM {
        int id
        int quantity
        string productCode

        float pricePerUnit
    }
```