ER Diagram

CIS 360 Business Database Concepts Assignment 2

E/R Diagramming Due October 3, 2012

The following assignment is to be drawn using any software drawing package you have access to (Gliffy, PowerPoint, Visio, etc.). Identify and label all components.

Make sure it is clear and easy to read. Professional quality is expected.

1. Draw an E/R diagram for the following situation: 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 his or her name and date-of-birth. If an employee is currently married to another employee of Projects, Inc., the date of marriage and who is married to whom must be stored; however, no record of marriage is required if an employee’s spouse is not also an employee. Each employee is given a job title (for example, engineer, admin assistant, foreman, and so on). We are interested in collecting more data specific to engineers and admin assistants. The relevant data to be recorded for engineers is the type of degree (e.g., electrical, mechanical, civil, etc.); for admin assistants, it is their typing speed. An employee does only one type of job at any given time, and we only need to retain information for an employee’s current job. There are 11 different departments, each with a unique name. An employee can report to only one department. Each department has a phone number. To procure various kinds of equipment, each department deals with many vendors. A vendor typically supplies equipment to many departments. We are required to store the name and address of each vendor. Many employees can work on a project. An employee can work in many projects (for example, Southwest Refinery, California Petrochemicals, and so on) but can only be assigned to at most one project in a given city. For each city, we are interested in its state and population. An employee can have many skills (preparing material requisitions, checking drawings, and so on), but (s)he may use only a given set of skills on a particular project. (For example, employee MURHPY may prepare requisitions for Southwest Refinery project and prepare requisitions as well as check drawings for California Petrochemicals.) Employees use each skill that they possess in at least one project. Each skill is assigned a number, and we must store a short description of each skill. Projects are distinguished by project numbers, and we must store the estimated cost of each project.