Database Concepts (7th Edition)
Database Concepts (7th Edition)
7th Edition
ISBN: 9780133544626
Author: David M. Kroenke, David J. Auer
Publisher: PEARSON
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Chapter 2, Problem 2.19RQ

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According to the reference of book, the terms “primary key” and “foreign key” are defined as follows:

Primary key:

  • Primary key is like a candidate key in which it uniquely identifies each row in a relation.
    • For example consider that there is an “Employee” table in which “emp_id” is unique so it is chosen as a primary key in database table.
    • In this book, primary keys are underlined.

Foreign key:

  • To maintain the relationship between the database tables, the values are placed from one relation to second relation.
  • The values used in first relation come under the primary key values whereas the values that are referred in second relation come under the foreign key...

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