If you have a vending machine with various products and payment methods, it's recommended you use a database to store all transactions in the vending machine.
Three data points that you should take care about are product, transaction, and machine vending capabilities. In general, we can describe the core database design as follows:
The Product table consists of product information, including quantity and price. If you look at the schema in the figure, there are two fields: product_code and product_vending_code. product_code is the internal manufacturing identity that the system will use for all transactions. You can put Stock Keeping Unit (SKU) data into this field. Each product usually has an SKU ID so we can use it for our product identity. Otherwise, the product_vending_code field is designed for identity numbers on vending machines. These are...