Given are the relation schemas (U, F) and (U,G) with U = {A, B, C, D,...

  

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Given are the relation schemas (U, F) and (U,G) with U = {A, B, C, D, E } and F={ABDE, B→ DE, AC, E→C}, G = {ACE, AE → D, B→ A}. a) Determine {A}, {B}, {D}& and {A, B} using the algorithm from the lecture. b) Indicate whether F and G are left-minimal and/or right-minimal. Briefly justify your answer. Provide equivalent FDs that are left-minimal and right-minimal, if applicable. c) Determine all keys in F and G. d) Is F in 2NF? Justify your answer. e) Is F in 3NF? Justify your answer. f) Is G in 2NF? Justify your answer. g) Is G in 3NF? Justify your answer. Voting Task 2 (FD-Equivalence) Given is U = { A, B, C, D, E } and the following sets of FDs: F₁ = {DE, D→ A, D → B, AB → CD}, F₂ = {D→ AE, DE → B, CD, AB → C}, F3 = {D ABCE, E→ B, C →→D. AB → C}. F₁ = {D→ ABCE, CABDE, ABCDE, EB}. (6x2=12 Punkte) We define two sets of FDs, F₁ and F2, as equivalent, i.e., F₁ F2, if they have the same FD-closure. Indicate which of the FD sets F₁ to F4 are equivalent. Briefly justify your decision each time. Various methods for proving the equivalence of FD sets were outlined in the script and on this exercise sheet. Which method you use is up to you. Given are the relation schemas (U, F) and (U,G) with U = {A, B, C, D, E } and F={ABDE, B→ DE, AC, E→C}, G = {ACE, AE → D, B→ A}. a) Determine {A}, {B}, {D}& and {A, B} using the algorithm from the lecture. b) Indicate whether F and G are left-minimal and/or right-minimal. Briefly justify your answer. Provide equivalent FDs that are left-minimal and right-minimal, if applicable. c) Determine all keys in F and G. d) Is F in 2NF? Justify your answer. e) Is F in 3NF? Justify your answer. f) Is G in 2NF? Justify your answer. g) Is G in 3NF? Justify your answer. Voting Task 2 (FD-Equivalence) Given is U = { A, B, C, D, E } and the following sets of FDs: F₁ = {DE, D→ A, D → B, AB → CD}, F₂ = {D→ AE, DE → B, CD, AB → C}, F3 = {D ABCE, E→ B, C →→D. AB → C}. F₁ = {D→ ABCE, CABDE, ABCDE, EB}. (6x2=12 Punkte) We define two sets of FDs, F₁ and F2, as equivalent, i.e., F₁ F2, if they have the same FD-closure. Indicate which of the FD sets F₁ to F4 are equivalent. Briefly justify your decision each time. Various methods for proving the equivalence of FD sets were outlined in the script and on this exercise sheet. Which method you use is up to you.

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a To determine the closure of sets A B D and A B using the given functional dependencies A Start with A Since there is no FD with A on the left side A ... View the full answer