Problem
Your consultancy firm has been asked to develop an application for a small wholesale grocery firm SLF. It sources grocery product from a limited number of suppliers across the world and delivers them to customers in the US. Interviews with the various stakeholders have revealed the following:
SLF employs a small number of employees. Each plays a specific role in the company (managing director, accountant, HR specialist, purchasing officer, order fulfillment officer). Employees, other than the managing director, are supervised by another employee.
SLF sources products from a limited number of suppliers around the world. It has a single supplier for each product.
SLF maintains an inventory of the products that it has on hand. When the number of products on hand falls below a certain limit, a message is sent to alert a purchasing officer. Since supplier orders often consist of orders for multiple products, the alert does not automatically lead to an order to a supplier. Instead, the purchasing officer will try to combine different orders for products from the same supplier into a single supplier order.
When a supplier order is made, the date on which it was made is recorded. When a supplier order is received, the date on which it was received is also recorded, and the number of products on hand in the inventory is automatically increased. The order also automatically generates a payment from SLF to the supplier. Once the order has been received, the payment amount is added to the supplier order.
SLF receives orders from customers in the US. A customer order typically consists of a number of different products. SLF records the date on which the order was received, and the date on which it was shipped. Again, SLF automatically calculates the payment due. When an order is shipped, the inventory is automatically updated.
Create an ERD for the above and export it as an image. Record any assumptions that were made in creating this ERD.