3. Consider the relation schema R = (A,B,C,D). For each of the following set of FDs, do the following: (a) identify the candidate keys for R. (b) state whether or not the proposed decomposition of R is lossless join and dependency preserving. Justify your answers. 1. B→C, A→D; decompose into (B,C) and (A,D). 2. AB→D, D→A, D→C; decompose into (A,C,D) and (B,D). 3. A→BC, C→AD; decompose into ABC and AD. 4. A→B, BC, C→D; decompose into AB and ACD. 5. A→B, BC, C→D; decompose into AB, AD and CD.

3. Consider the relation schema R = (A,B,C,D). For each of the following set of FDs, do the following: (a) identify the candidate keys for R. (b) state whether or not the proposed decomposition of R is lossless join and dependency preserving. Justify your answers. 1. B→C, A→D; decompose into (B,C) and (A,D). 2. AB→D, D→A, D→C; decompose into (A,C,D) and (B,D). 3. A→BC, C→AD; decompose into ABC and AD. 4. A→B, BC, C→D; decompose into AB and ACD. 5. A→B, BC, C→D; decompose into AB, AD and CD.

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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