(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 → F, D→CE} of functional dependencies. Show each step.
(1) Find a minimal cover for the relation... (a) R = (A, B, C, D, E,...
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...
Consider the following relation R(A,B,C,D,E,G) and the set of functional dependencies F = { A → BCD BC → DE B → D D → A} Give a 3NF decomposition of the given schema based on a canonical cover
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
5. [5 points] Let relation R (A, B, C, D, E) satisfy the following functional dependencies: AB → C BC → D CD → E DE → A AE → B Which one of the following FDs is also guaranteed to be satisfied by R? A. B. BCD → A A-B D. CE → 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
Given the following relation schemas and the sets of FD's: a- R(A,B,C,D) F={ABẠC,C7D, D´A, BC+C} b- R(A,B,C,D) F={BẠC, BD, AD>B} C- R(A,B,C,D) F={AB-C, DC+D, CD+A, AD+B} d- R(A,B,C,D) F={AB=C, C+D, D™B, DE} e- R(A, B, C, D, E) F= {AB+C, DB+E, AE>B, CD+A, ECD} In each case, (i) Give all candidate keys (ii) Indicate the BCNF violation Give the minimal cover and decompose R into a collection of relations that are BCNF. Is it lossless? Does it preserve the dependencies?...
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 the schema R=(A, B, C, D, E) and let the following set F of functional dependencies hold for R: F= {A → BC, CD → E, B D } Problem 3 Suppose that the schema R=(A, B, C, D, E) is decomposed into R/ - (A, B, C) and R=(A, D, E). Show if this decomposition is a lossless decomposition with respect to the given set of functional dependencies F.
Given R = (A, B, C, D, E, G, H, I) and the set F of functional dependencies: BDEI → GH EG → AI DH → CE I → BD use the BCNF algorithm to generate a database design. Is your design dependency-preserving? Why or why not?
5c. Consider the relation R(ABCDE) with the set of functional dependencies F={BE→D, DE→A, AD→C, B→E}. Using decomposition, find a lossless, dependency preserving, BCNF set of relations for R, if such exists. Be sure to identify the projections of the functional dependencies onto the resulting relations at each stage of the decomposition.