Journal of Information Systems Education (JISE)

Volume 8

Volume 8, Number 1, Pages 33-35

Spring 1996


Teaching Students How to Find the Candidate Keys of a Relational Database Schema


Hossein Saiedian
University of Nebraska at Omaha
Omaha, NE 68182, USA

Abstract: While most database textbooks provide formal and informal definitions for the candidate key of a relational database scheme, none provide a simple approach for finding the keys. In this paper, we present a simple algorithm that can be used by the students to correctly and efficiently identify the candidate keys of a relational database schema. The algorithm examines the position of attributes in the functional dependencies to determine which attributes are essential and useful for determining the keys and which attributes should be ignored. A key is found by computing the closure of essential attributes.

Keywords: Relational database, Candidate keys, Functional dependencies

Download this article: JISEv8n1p33.pdf


Recommended Citation: Saiedian, H. (1996). Teaching Students How to Find the Candidate Keys of a Relational Database Schema. Journal of Information Systems Education, 8(1), 33-35.