Lectures / LECTURE 2

Tools

•MS Visio

•gliffy.com

•ERwin

•ER/Studio

•DBDesigner4

•etc.

Constraints

Finding constraints is part of the modeling process. Commonly used constraints:

•Keys: social security number uniquely identifies a person.

•Single-value constraints: a person can have only one father.

•Other constraints: peoples’ ages are between 0 and 150.

Books

•Connolly, Thomas M. Database Systems: A Practical Approach to Design, Implementation, and Management / Thomas M. Connolly, Carolyn E. Begg.- United States of America: Pearson Education

•Garcia-Molina, H. Database system: The Complete Book / Hector

Garcia-Molina.- United States of America: Pearson Prentice Hall

•Sharma, N. Database Fundamentals: A book for the community by the community / Neeraj Sharma, Liviu Perniu.- Canada

Questions

1. The column of a table is referred to as the

a)Tuple

b)Attribute

c)Entity

d)Degree

Questions

2. The another name for a row is

a)Tuple

b)Attribute

c)Entity

d)Degree

Questions

3. A primary key for an entity is

a)A tuple

b)Any attribute

c)A unique attribute

d)A relationship

Questions

4. In E-R Diagram relationship type is represented by

a)Ellipse

b)Dashed ellipse

c)Rectangle

d)Diamond (rhombus)

Questions

5. Key to represent relationship between tables is called

a)Primary key

b)Secondary Key

c)Foreign Key

d)None of these

Questions

6. An entity relationship diagram is a tool to represent

a)Data model

b)Process model

c)Event model

d)Customer model