Consider the relation R with attributes: A, B, C, D, E, and F Let S be...
Here's a relation (R), its attributes and its functional dependencies (F): R(A, B, C, D, E) C D → B A → D D → C E → C What is the closure of AB ({AB}+)? What is the closure of F (F+)? [ set of closures for all LHS][each LHS on one line] What is the minimal set (cover) for F? Provide a key for relation R (a minimal set of attributes that can determine all attr.) Decompose the...
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subject: Database Systems
QUESTION 8 Consider the relation R(A,B,C,D,E,F) with FDs A -> C,B->D, C-> E, D -> F. Consider the BCNF status of R. Which of the following could be correct given the information above? 1. Ris in BCNF already. 2. Ris not in BCNF. It must be divided into R1(A,C,E) with FDs A->C, C-> E, and R2(B,D,F) with FDs B -> D, D -> F. 3. R is not in BCNF. It must...
Consider a relation R with five attributes A, B, C, D, and E. You are given the following functional dependencies: A → B, BC→E, and ED→A. (a) Is R in BCNF? If it is not, decompose it into a collection of BCNF relations. 2: BCNF and 3NF (3 points) Consider the relation schema R with attributes A, B, C, and D and the following functional dependencies: AB→C, AC→B, B→D, BC→A. (a) Is R in BCNF? If it is not, decompose...
Consider a relation schema R with attributes ABCDEFGH with functional dependencies S: S={B→CD, BF→H, C→AG, CEH→F, CH→B} Employ the BCNF decomposition algorithm to obtain a lossless decomposition of R into a collection of relations that are in BCNF. Make sure it is clear which relations are in the final decomposition and project the dependencies onto each relation in that final decomposition.
Question 1: Functional Dependencies [7 marks Consider a relation R on attributes (A, B, C, D, E, F,G, H) and the following functional dependen- cies. B →G C →D DE →GC → EF DEF → H (a) What is the closure of [F, G, Hy? (b) List all of the candidate keys of R under the dependencies above. (c) List all of the FDs above that are 3NF violations (d) List all of the FDs above that are BCNF violations....
Consider the following relation R = {A,B,C,D,E} and the following set of functional dependencies F = { A → BC CD → E B → D E → A} F = { A → BC CD → E B → D E → A} Give a lossless, dependency-preserving decomposition into 3NF of schema R
Given a schema R (A, B, C, D, E, F)and a set Fof functional dependencies {A →B, A →D, CD →E, CD →F, C →F, C →E, BD →E}, find the closure of the set of functional dependencies ?+
Consider a relation R with ve attributes A, B, C, D, and E. You are given the following functional dependencies: A->B, BC->E, and ED->A. (a) List all keys for R. (10 points) (b) Is R in BCNF? If it is, explain why. If is not, decompose it into a collection of BCNF relations. (20 points) (c) Is R in 3NF? If it is, explain why. If it is not, convert it into a collection of 3NF relations. (20 points)
(1) Find a minimal cover for the relation... (a) R = (A, B, C, D, E, F, G, H) with the set F = {A →B, ABCD→E, EF→GH, ACDF→EG} of functional dependencies. Show each step. (b) R = (A, B, C, D, E) with the set F = {A→BC, CD→E, B→D, E→A} of functional dependencies. Show each step. (c) R = (A, B, C, D, E, F) with the set F = {A → D, AC → DE, B →...
Consider the following relation R= {A, B, C, D, E} and the following set of functional dependencies F={ A → BC CD → E B + D E + A} Give a lossless, dependency-preserving decomposition into 3NF of schema R