Problem
A store decides to go High Tech. You are asked to design a database for the store After brainstorming with the store managers. you come up with the followings specification
A. The store has multiple departments, identified by their names, each department may have many employees but (at most} one of them is the department manager
B. Employees are identified by their names. We also need to record their salaries. Each employee works in exactly one department. Managers are employees as well, each with a salary higher than all other employee's in the department he manages
C. The store sells various items identified by item ID's. Exactly one department carries each item. while each department may carry many items. For each item we also need to keep short description and its quantity in stocks
D. The store deals with a number of suppliers Identified by their names. We need to record their addresses
E. Each supplier supplies an item at a particular price. A supplier may supply any number of items. and each item must be supplied by at least 3 suppliers (probably different prices).
F. The store receives orders identified by order ID 's. Each order has a date, a shipping address, and may include different quantities of multiple items.
• Identifying the entities and set their attributes
• Draw E-R model and indicate the maximum cardinalities and existence.