Star Hoist is owned by Darth and his wife Ella Vader. The company has had its ups and downs since Darth and Ella built it from the ground up several years ago. The company had some initial difficulties when Darth's brother, Tacksi, was their accountant and got in trouble with the IRS. Finally, the company is doing well, and the owners are ready to expand the business to new heights. Star Hoist sells and installs replacement parts for lifts and similar equipment from a variety of manufacturers. Business can be very competitive, especially from the original manufacturers, which directly sell replacement parts and service to end customers. Darth and Ella need every aspect of their business to work smoothly so that they don't get the shaft in deals with customers. Darth and Ella try to encourage their employees to do the best they can for each customer, which is symbolized by the company motto: "Oh, be the one." There are many rogue competitors, so accurate service is also key for Star Hoist.

You are to draw an ERD for Star Hoist. The fundamental need for Star Hoist is a computer database to keep track of their in-house inventory and of installed parts. Because the business offers negotiated warranties with customers, all parts installed at customer sites need to be tracked. Each part instance is identified by a number assigned by Ella, but because a particular part might come from the original manufacturer or an alternative supplier, the database must record the source of each part and its sup- plier's part number. In general, a part has a description and standard prices that Star Hoist charges a customer for the part and its installation. Each instance of the part has a cost to Star, based on what the supplier actually charged when Star Hoist acquired that part (many parts, due to their materials, have frequent price changes). Each particular part instance must be tracked, whether it is in inventory or sold to a particular customer. When a part is sold to a customer, there is a negotiated warranty end date, until which time Star assumes all replacement costs for the part, and an actual selling and installation price. Customers have a name, account number, contact per- son name, and a code that specifies special terms that have been negotiated with each customer. Each supplier has a name, Star's account number with that supplier, and the phone number for the supplier. Each supplier can supply only certain parts. Because many parts can be sourced from multiple suppliers, each part in inven- tory or installed at a customer must be associated with its source supplier; in addition, Star also needs to know which suppliers can supply which parts. Because many of the parts are very expensive, Darth has placed a limit on how many part instances of a given part can be held in the company's inventory. The limit is three part instances to be held in inventory. As Darth tells the customers, "May the fourth be with you."

-You must provide the entities, relationships, cardinalities, all the identifiers and the attributes. Remember, primary identifiers should be bolded and underlined

- State any assumptions you believe you have to make in order to develop a complete diagram. You may add additional entities and attributes if you think they improve the ERD, but you should explain why they'd improve the solution.

- This is a design exercise that involves some creative decision-making. So, there is no single correct answer. You should reflect on our class discussions on creating the most direct relationship among entities, avoiding redundant relationships, seeking clarification if the business rules are not clear, etc.

- If you believe your diagram will impose some non-obvious constraints on what data can be stored, you should outline them as well