Overview. The process is designed to handle the interaction with customers and suppliers, and also deals with stock control. Invoice and payment data is recorded. For clarity I have noted down the following: o Head Office consists of - Product Management Finance Sales A Local Branch consists of - A Local Office Warehouse Distribution Preliminary List of Entities.
In my top-down analysis of the Metropolitan Pharmaceuticals scenario, I have first attempted to produce a preliminary list of candidate entities. These are as follows: o Customero Customer Ordero Customer Invoiceo Sales - Occurs only once so isn't include do Producto Product Ordero Suppliero Supplier Invoice o Finance - Occurs only once so isn't include do Local Brancho Local Office - Is part of Local Branch so isn't include do Distribution - Is part of Local Branch so isn't include do Warehouse - Is part of Local Branch so isn't include do Stock The following page shows my list of probable entities: List of Probable Entities. o Customero Customer Ordero Customer Invoiceo Producto Product Ordero Suppliero Supplier Invoice o Local Brancho Stock Descriptions and expected essential attributes for the above entities: Since the system analysis is focused on dealing with customers, suppliers and handling products, I have included all entities which I believe participate in these activities. o Customer Description: Retail chemist shops or pharmacies associated with shops, hospitals or medical practices. All require a supply of products from the Metropolitan Pharmaceuticals system. Attributes: Customer ID - Identifying attribute Name Address Telephone Number Fax Number e-mail Contact Name Delivery Address Credit Rating Customer Order Description: An order placed by the Customer requesting the delivery of product.
Attributes: Order Number - Identifying attribute Customer ID Product IDQuantityo Customer Invoice Description: An invoice sent to the Customer from the Finance department, requesting payment for the delivered goods. Attributes: Invoice Number - Identifying attribute Order IDDateAmount to be pai do Product Description: An item that is supplied by the Metropolitan Pharmaceuticals system. Attributes: Product ID - Identifying attribute Name Description Category - (A, B, C or D) Stock Item - (Yes or No) o Product Order Description: An order that is sent to either the Supplier (if it is a non-stock item) or a Local Branch (if it is a stocked item), requesting the delivery of a product to a customer. Attributes: Order Number - Identifying attributeDateProductCustomer ID Quantity Supplier Description: A company that is able to supply a range of products to Metropolitan Pharmaceuticals. Metropolitan Pharmaceuticals does not manufacture any of its products, but instead, uses suppliers who either produce or procure the products.
Attributes: Supplier ID - Identifying attributeNameAddressTelephone Number Fax Number e-mail o Supplier Invoice Description: An invoice that is sent by the supplier to Metropolitan Pharmaceuticals requesting payment for the product it has provided. Attributes: Invoice Number - Identifying attribute Date Amount to be pai do Local Branch Description: A local outlet that contains a Local Office, a Warehouse and a Distribution Center. Attributes: Branch ID - Identifying attribute Name Address Telephone Number Stock Description: A full inventory of products that are held in stock at the local branch. Attributes: Stock ID - Identifying attribute Product ID Location - eg.
Shelf number Quantity Re-Order level Entity Links or Dependencies. Now to identify which pairs of entities have an association between themselves. o Customer is related to Customer Order: Justification: Customer places Customer Order Customer Order is placed by Customero Customer is related to Customer Invoice: Justification: Customer receives Customer Invoice Customer Invoice is received by Customero Customer Order is related to Local Branch: Justification: Customer Order is received by Local Branch Local Branch receives Customer Ordero Local Branch is related to Stock: Justification: Stock is held by Local Branch Local Branch holds Stock Local Branch is related to Product: Justification: Product is received by Local Branch Local Branch receives Producto Local Branch is related to Product Order: Justification: Local Branch requests Product Order Product order is requested by Local Brancho Product Order is related to Supplier: Justification: Product Order is received by Supplier Supplier receives Product Ordero Product is related to Supplier: Justification: Product is sent by Supplier Supplier sends product Supplier is related to Supplier Invoice: Justification: Supplier sends Supplier Invoice Supplier Invoice is sent by Supplier The following page shows my preliminary Entity Relationship diagram. I have chosen Local Branch as the central active entity.