{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

chapter 3 in-class exercises - CGS 2545 Database Concepts...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
CGS2545: Database Concepts (Chapter 3 Exercises) Page 1 © Mark Llewellyn CGS 2545: Database Concepts Spring 2010 Chapter 3 – In Class Exercises School of Electrical Engineering and Computer Science University of Central Florida Instructor : Dr. Mark Llewellyn [email protected] HEC 236, 407-823-2790 http://www.cs.ucf.edu/courses/cgs2545/spr2010
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
CGS2545: Database Concepts (Chapter 3 Exercises) Page 2 © Mark Llewellyn The entity type STUDENT has the following attributes: Student_Name, Address, Phone, Age, Activity, and No_of_years. Activity represents some campus-based student activity, and No_of_years represents the number of years the student has engaged in this activity. A given student may engage in more than one activity. Scenario #1
Background image of page 2
CGS2545: Database Concepts (Chapter 3 Exercises) Page 3 © Mark Llewellyn ERD For Scenario #1 Derived attribute Simple attributes Key attribute Multi-valued attribute Composite attribute
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
CGS2545: Database Concepts (Chapter 3 Exercises) Page 4 © Mark Llewellyn A company has a number of employees. The attributes of EMPLOYEE include Emp_ID (identifier), Name, Address, and Birthdate. The company also has several projects. Attributes of PROJECT include Proj_ID (identifier), Proj_Name, and Start_Date. Each employee may be assigned to one or more projects, or may not be assigned to any project. A project must have at least one employee assigned to it, and may have any number of employees assigner to it. An employee’s billing rate may vary by project, and the company wishes to record the applicable billing rate (Billing_Rate) for each employee when assigned to a particular project.
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}