Question

Problem 4: Given the relation R(A, B, C, D) with FDs A ? B and BC ? D, if we projected attributes A, B, C, i.e. R1 := ?<sub>A,B,C</sub>(R) What is the minimal basis, T for our new relation R1? a. Compute the closure table for R1 {A}+ = {B}+ = {C}+ = {AB}+= {AC}+ {BC}+ {ABC}+ b. Identify all non-trivial FDs that follow from R1 given the FDs from relation R. c. Find the minimal basis of T for R1.

          Problem 4: Given the relation R(A, B, C, D) with FDs A ? B and BC ? D, if we projected attributes A, B, C, i.e. R1 := ?<sub>A,B,C</sub>(R)
What is the minimal basis, T for our new relation R1?
a. Compute the closure table for R1
{A}+ =
{B}+ =
{C}+ =
{AB}+=
{AC}+
{BC}+
{ABC}+
b. Identify all non-trivial FDs that follow from R1 given the FDs from relation R.
c. Find the minimal basis of T for R1.

Problem 4: Given the relation R(A, B, C, D) with FDs A ? B and BC ? D, if we projected attributes A, B, C, i.e. R1 := ?<sub>A,B,C</sub>(R)
What is the minimal basis, T for our new relation R1?
a. Compute the closure table for R1
A+ =
B+ =
C+ =
AB+=
AC+
BC+
ABC+
b. Identify all non-trivial FDs that follow from R1 given the FDs from relation R.
c. Find the minimal basis of T for R1.

Added by Thomas M.

Computer Science and Information Technology

Trishna Knowledge Systems 2018 Edition

Instant Answer

Solved by Expert Akash M

11/29/2023

Step 1

Step 1: Compute the closure table for R1 - Start with the given FDs A->B and BC->D - Calculate the closure of each attribute set: - {A}+ = {A, B} (from A->B) - {B}+ = {B} - {C}+ = {C} - {AB}+ = {A, B} - {AC}+ = {A, C} - {BC}+ = {B, C, D} (from BC->D) Show more…

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Problem 4: Given the relation R(A,B,C,D) with FDs A->B and BC->D, if we projected attributes A,B, C, i.e. R1:=Pi _(A,B,C)(R) What is the minimal basis, T for our new relation R1 ? a. Compute the closure table for R1 b. Identify all non-trivial FDs that follow from R1 given the FDs from relation R. c. Find the minimal basis of T for R1. Problem 4:Given the relation R(A, B,C,D) with FDs A B and BC D, if we projected attributes A, B, C,i.e.R1 =IIA.B.c(R) What is the minimal basis,T for our new relation R1? a.Compute the closure table for R1 {A}+= {B}+= {C}+= {AB}+= {AC}+ {BC}+ {ABC}+ b. Identify all non-trivial FDs that follow from R1 given the FDs from relation R. Find the minimal basis of T for R1