1. Draw an ER Diagram for the following (record any assumptions):
Projects Inc. is an engineering firm with approximately 500 employees. A database is required to keep track of all employees, their skills, projects assigned and departments worked in. Every employee has a unique number assigned by the firm, required to store her or his name and data of birth. If an employee is currently married to another employee of Projects Inc, the data of the marriage and who the employee is married to must be stored. However no record of marriage is required if the spouse is not also an employee. Each employee is given a job title. An employee does only one type of job at any given time, and we only need to store information for the employees current job.
There are 11 different departments each with a unique name. An employee can report to only one department. Each department h as a phone number. To purchase various types of equipment each department deals with different vendors. A vendor usually supplies equipment to many departments. We must store the name and address of each vendor, and the date of the last meeting between a department and a vendor.
Many employees can work on a project. An employee can work on many projects but can be assigned to at most one project in a given city. For each city, we are interested in the state and population. An employee can have many skills. Each skill is assigned a number, and we must also store a description of each skill. Projects are identified by project numbers and we must store the estimated cost of each project.

2. Draw an ER Diagram for the following (record any assumptions):
The R.W. Waters School of Business operates an international business program in 10 locations throughout Europe. The school had its first class of graduates in The school keeps track of each graduate’s student number, name (when they were a student), country of birth, current country of citizenship, current name, current address, name of each major completed (each student has one or two majors), and a description of each major. In order to keep a strong relationship with alumni, the school holds various events around the world. Events have a title, date, location and type. The school wants to keep track of which graduates have attended which events. For an attendance by a graduate at an event, a comment is recorded about information school officials learned from that graduate, at that event.
The school also keeps in contact with graduates by mail, , telephone and fax interactions. Also, like with events, the school records information learned from the graduate from each of these contacts.
The school also maintains contact with the spouse(husband/wife) of a graduate. The school tracks the spouses name and the spouses current address. Each spouse is identified by their address, combined with the student number of the graduate they are related to.

3. Draw an ER Diagram for the following (record any assumptions):
Stillwater Antiques buys and sells one-of-a-kind antiques of all kinds. Each item is uniquely identified by an item number and is also characterized by a description, asking price, condition, and open ended comments. Stillwater works with many different individuals called clients, who sell items to and buy items from the store. Some clients only sell items to Stillwater, some only buy items, and others both sell and buy. A client is identified by a client number, and is also described by client name, and client address. When Stillwater sells an item in stock to a client, the owner wants to record the commission paid, the selling price, sales tax and date sold. When Stillwater buys an item from a client, the owner wants to record the purchase cost, the date purchased and condition at the time of purchase.
Stillwater also tracks information about various banks that they work with. Bank information includes the name of the bank, and the name of the contact at the bank with a phone number. Each item is appraised(value is determined) by the bank. The appraisal is good for 1 year, so when an item is appraised by the bank, an expiry date is recorded. New appraisals are completed once the previous appraisal expires.