Create a Full ERD

A grocery chain needs a database designed in order to keep track of inventory and sales; the scenario to model is as follows:

A customer goes to one of the stores to make a purchase, which contains one or more products. The employee ID of the cashier will be stored for the purchase; if the customer is a member of the loyalty program, his membership ID will be associated with the purchase as well (although this is not required).

Each product will have a description and current price (applied to all stores); stock inventory count for these products will be tracked for each store.

The purchase amount will be the total of all product prices multiplied by their quantity. After the customer pays, the purchase should be marked as paid, and the stock inventory count for all items in the purchase should be reduced for that store accordingly.