Answer)
R = (A,B,C,D,E)
FD's:
A,B --> E
C,D --> E
A --> C
C --> A
Step 1:
FD A,B --> E violates.
Table is split:
R1 = (A,B,E,C)
R2 =(A,B,D)
Step 2:
Checking whether R1 is in BCNF:
FD A --> C violates.
R3 = (A,C)
R4 = (A,B,E)
Step 3:
Checking whether R2 is in BCNF:
Yes, already in BCNF.
R3 and R4 are also in BCNF.
Thus:
R3 = (A,C)
R4 = (A,B,E)
R2 =(A,B,D)
are the final tables in BCNF.
4. (4 points) Consider the relation RCA, B, C, D, E) with the set of FDs:...
Let R(A,B,C,D,E) be a relation with FDs F = {AB-C, CD-E, E–B} (2 Points) Select one: O Ris in 3NF but not in BCNF. O Ris not in 3NF but in BCNF. O Ris in 3NF and in BCNF. R is not in 3NF and not in BCNF.
This question is from the 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...
For the following relations and set of FDs: 1. give a key for the relation; 2. state whether the relation is in BCNF, and if it is not state why: 3. give a set of relations in 3NF equivalent to the original relation 1. (33 points) What is the closure of (A,B) with respect to R(A,B,C,D,E,F,G)if R has the following functional dependencies? (a) GCDE AF BF - ABC FC G (b) D-AC-D A+B ABC 2 33 points for each of...
Let R(A, B, C, D, E) be a relation wit FDs F = {AB->C, CD->E, E->B, CE->A}.... Question 4 Not yet answered Marked out of 2.00 P Flag question Let R(A,B,C,D,E) be a relation with FDs F = {AB-C, CD-E, E-B, CE-A} Consider an instance of this relation that only contains the tuple (1, 1, 2, 2, 3). Which of the following tuples can be inserted into this relation without violating the FD's? (2 points) Select one: 0 (0, 1,...
Let R(A,B,C,D,E) be a relation with FDs F = {AB-CD, A-E, C-D, D-E} The decomposition of Rinto R1(A, B, C), R2(B, C, D) and R3(C, D, E) is 2 Points) Select one: Lossless and Dependency Preserving. Lossy and Not Dependency Preserving. Lossless and Not Dependency Preserving. Lossy and Dependency Preserving.
Let R(A,B,C,D,E) be a relation with FDs F = {AB-CD, A-E, C-D, D-E} The decomposition of Rinto R1(A, B, C), R2(B, C, D) and R3(C, D, E) is 2 Points) Select one: Lossless and Dependency Preserving. Lossy and Not Dependency Preserving. Lossless and Not Dependency Preserving. Lossy and Dependency Preserving.
Let R(A,B,C,D,E) be a relation with FDs F = {AB-CD, A-E, C-D, DE} The decomposition of R into R1(A, B, C), R2(B, C, D) and R3(C, D, E) is (2 Points) Select one: Lossy and Dependency Preserving. Lossless and Not Dependency Preserving. Lossy and Not Dependency Preserving. Lossless and Dependency Preserving.
Consider relation R(A,B,C,D) with functional dependencies: B → C D→ A BA → D CD → B Decompose R into Boyce-Codd Normal Form (BCNF). Clearly show all intermediary steps.
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 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)