Q1: The select (o) operation and (∞) join operations are commutative. Give one scenario or case under which the right hand side of the following equivalence rule is more efficient that its left hand side, explain your answer: (1) Oc1(0c2(R)) = 0c2(0c1(R)) (2) Rab S = S 00a-b R (when nested block join algorithm is used) Where ∞ is an equi-join operation R and S are tables a is an attribute in R b is an attribute in S c1, and c2 are conditions

Q1: The select (o) operation and (∞) join operations are commutative. Give one scenario or case under which the right hand side of the following equivalence rule is more efficient that its left hand side, explain your answer: (1) Oc1(0c2(R)) = 0c2(0c1(R)) (2) Rab S = S 00a-b R (when nested block join algorithm is used) Where ∞ is an equi-join operation R and S are tables a is an attribute in R b is an attribute in S c1, and c2 are conditions

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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