7. 7 of 40 Suppose R is a Many To One relationship from entity set E1={b1,b2,b3} to E2={a1,a2,a3,a4}. Which of the following can NOT be a valid instance of R? Select one: O All of the five instances. OR = {(b3 a4)} OR = {(b1, a1), (b2, a2), (b2, a3)} OR = {(b1, a1), (b2, a2), (b3, a2)} OR= {(b1, a3), (b2, a1), (b3,a2)} None of the five instances. OR = {}

7. 7 of 40 Suppose R is a Many To One relationship from entity set E1={b1,b2,b3} to E2={a1,a2,a3,a4}. Which of the following can NOT be a valid instance of R? Select one: O All of the five instances. OR = {(b3 a4)} OR = {(b1, a1), (b2, a2), (b2, a3)} OR = {(b1, a1), (b2, a2), (b3, a2)} OR= {(b1, a3), (b2, a1), (b3,a2)} None of the five instances. OR = {}

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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